Quagga (http://www.quagga.net)


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Quagga

Quagga is an advanced routing software package that provides a suite of TCP/IP based routing protocols. This is the Manual for Quagga 0.99.17.6. Quagga is a fork of GNU Zebra.

Copyright © 1999-2005 Kunihiro Ishiguro, et al.

Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies.

Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one.

Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that this permission notice may be stated in a translation approved by Kunihiro Ishiguro.

Table of Contents


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1 Overview

Quagga is a routing software package that provides TCP/IP based routing services with routing protocols support such as RIPv1, RIPv2, RIPng, OSPFv2, OSPFv3, BGP-4, and BGP-4+ (see Supported RFCs). Quagga also supports special BGP Route Reflector and Route Server behavior. In addition to traditional IPv4 routing protocols, Quagga also supports IPv6 routing protocols. With SNMP daemon which supports SMUX protocol, Quagga provides routing protocol MIBs (see SNMP Support).

Quagga uses an advanced software architecture to provide you with a high quality, multi server routing engine. Quagga has an interactive user interface for each routing protocol and supports common client commands. Due to this design, you can add new protocol daemons to Quagga easily. You can use Quagga library as your program's client user interface.

Quagga is distributed under the gnu General Public License.


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1.1 About Quagga

Today, TCP/IP networks are covering all of the world. The Internet has been deployed in many countries, companies, and to the home. When you connect to the Internet your packet will pass many routers which have TCP/IP routing functionality.

A system with Quagga installed acts as a dedicated router. With Quagga, your machine exchanges routing information with other routers using routing protocols. Quagga uses this information to update the kernel routing table so that the right data goes to the right place. You can dynamically change the configuration and you may view routing table information from the Quagga terminal interface.

Adding to routing protocol support, Quagga can setup interface's flags, interface's address, static routes and so on. If you have a small network, or a stub network, or xDSL connection, configuring the Quagga routing software is very easy. The only thing you have to do is to set up the interfaces and put a few commands about static routes and/or default routes. If the network is rather large, or if the network structure changes frequently, you will want to take advantage of Quagga's dynamic routing protocol support for protocols such as RIP, OSPF or BGP.

Traditionally, UNIX based router configuration is done by ifconfig and route commands. Status of routing table is displayed by netstat utility. Almost of these commands work only if the user has root privileges. Quagga has a different system administration method. There are two user modes in Quagga. One is normal mode, the other is enable mode. Normal mode user can only view system status, enable mode user can change system configuration. This UNIX account independent feature will be great help to the router administrator.

Currently, Quagga supports common unicast routing protocols. Multicast routing protocols such as BGMP, PIM-SM, PIM-DM may be supported in Quagga 2.0. MPLS support is going on. In the future, TCP/IP filtering control, QoS control, diffserv configuration will be added to Quagga. Quagga project's final goal is making a productive, quality, free TCP/IP routing software.


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1.2 System Architecture

Traditional routing software is made as a one process program which provides all of the routing protocol functionalities. Quagga takes a different approach. It is made from a collection of several daemons that work together to build the routing table. There may be several protocol-specific routing daemons and zebra the kernel routing manager.

The ripd daemon handles the RIP protocol, while ospfd is a daemon which supports OSPF version 2. bgpd supports the BGP-4 protocol. For changing the kernel routing table and for redistribution of routes between different routing protocols, there is a kernel routing table manager zebra daemon. It is easy to add a new routing protocol daemons to the entire routing system without affecting any other software. You need to run only the protocol daemon associated with routing protocols in use. Thus, user may run a specific daemon and send routing reports to a central routing console.

There is no need for these daemons to be running on the same machine. You can even run several same protocol daemons on the same machine. This architecture creates new possibilities for the routing system.

     +----+  +----+  +-----+  +-----+
     |bgpd|  |ripd|  |ospfd|  |zebra|
     +----+  +----+  +-----+  +-----+
                                 |
     +---------------------------|--+
     |                           v  |
     |  UNIX Kernel  routing table  |
     |                              |
     +------------------------------+
     
         Quagga System Architecture

Multi-process architecture brings extensibility, modularity and maintainability. At the same time it also brings many configuration files and terminal interfaces. Each daemon has it's own configuration file and terminal interface. When you configure a static route, it must be done in zebra configuration file. When you configure BGP network it must be done in bgpd configuration file. This can be a very annoying thing. To resolve the problem, Quagga provides integrated user interface shell called vtysh. vtysh connects to each daemon with UNIX domain socket and then works as a proxy for user input.

Quagga was planned to use multi-threaded mechanism when it runs with a kernel that supports multi-threads. But at the moment, the thread library which comes with gnu/Linux or FreeBSD has some problems with running reliable services such as routing software, so we don't use threads at all. Instead we use the select(2) system call for multiplexing the events.


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1.3 Supported Platforms

Currently Quagga supports gnu/Linux and BSD. Porting Quagga to other platforms is not too difficult as platform dependent code should most be limited to the zebra daemon. Protocol daemons are mostly platform independent. Please let us know when you find out Quagga runs on a platform which is not listed below.

The list of officially supported platforms are listed below. Note that Quagga may run correctly on other platforms, and may run with partial functionality on further platforms.



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1.4 Supported RFCs

Below is the list of currently supported RFC's.

RFC1058
Routing Information Protocol. C.L. Hedrick. Jun-01-1988.
RF2082
RIP-2 MD5 Authentication. F. Baker, R. Atkinson. January 1997.
RFC2453
RIP Version 2. G. Malkin. November 1998.
RFC2080
RIPng for IPv6. G. Malkin, R. Minnear. January 1997.
RFC2328
OSPF Version 2. J. Moy. April 1998.
RFC2370
The OSPF Opaque LSA Option R. Coltun. July 1998.
RFC3101
The OSPF Not-So-Stubby Area (NSSA) Option P. Murphy. January 2003.
RFC2740
OSPF for IPv6. R. Coltun, D. Ferguson, J. Moy. December 1999.
RFC1771
A Border Gateway Protocol 4 (BGP-4). Y. Rekhter & T. Li. March 1995.
RFC1965
Autonomous System Confederations for BGP. P. Traina. June 1996.
RFC1997
BGP Communities Attribute. R. Chandra, P. Traina & T. Li. August 1996.
RFC2545
Use of BGP-4 Multiprotocol Extensions for IPv6 Inter-Domain Routing. P. Marques, F. Dupont. March 1999.
RFC2796
BGP Route Reflection An alternative to full mesh IBGP. T. Bates & R. Chandrasekeran. June 1996.
RFC2858
Multiprotocol Extensions for BGP-4. T. Bates, Y. Rekhter, R. Chandra, D. Katz. June 2000.
RFC2842
Capabilities Advertisement with BGP-4. R. Chandra, J. Scudder. May 2000.
RFC3137
OSPF Stub Router Advertisement, A. Retana, L. Nguyen, R. White, A. Zinin, D. McPherson. June 2001

When SNMP support is enabled, below RFC is also supported.

RFC1227
SNMP MUX protocol and MIB. M.T. Rose. May-01-1991.
RFC1657
Definitions of Managed Objects for the Fourth Version of the Border Gateway Protocol (BGP-4) using SMIv2. S. Willis, J. Burruss, J. Chu, Editor. July 1994.
RFC1724
RIP Version 2 MIB Extension. G. Malkin & F. Baker. November 1994.
RFC1850
OSPF Version 2 Management Information Base. F. Baker, R. Coltun. November 1995.


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1.5 How to get Quagga

The official Quagga web-site is located at:

http://www.quagga.net/

and contains further information, as well as links to additional resources.

Quagga is a fork of GNU Zebra, whose web-site is located at:

http://www.zebra.org/.


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1.6 Mailing List

There is a mailing list for discussions about Quagga. If you have any comments or suggestions to Quagga, please subscribe to:

http://lists.quagga.net/mailman/listinfo/quagga-users.

The Quagga site has further information on the available mailing lists, see:

http://www.quagga.net/lists.php


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1.7 Bug Reports

If you think you have found a bug, please send a bug report to:

http://bugzilla.quagga.net

When you send a bug report, please be careful about the points below.

Bug reports are very important for us to improve the quality of Quagga. Quagga is still in the development stage, but please don't hesitate to send a bug report to http://bugzilla.quagga.net.


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2 Installation

There are three steps for installing the software: configuration, compilation, and installation.

The easiest way to get Quagga running is to issue the following commands:

     % configure
     % make
     % make install


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2.1 Configure the Software


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2.1.1 The Configure script and its options

Quagga has an excellent configure script which automatically detects most host configurations. There are several additional configure options you can use to turn off IPv6 support, to disable the compilation of specific daemons, and to enable SNMP support.

--enable-guile
Turn on compilation of the zebra-guile interpreter. You will need the guile library to make this. zebra-guile implementation is not yet finished. So this option is only useful for zebra-guile developers.
--disable-ipv6
Turn off IPv6 related features and daemons. Quagga configure script automatically detects IPv6 stack. But sometimes you might want to disable IPv6 support of Quagga.
--disable-zebra
Do not build zebra daemon.
--disable-ripd
Do not build ripd.
--disable-ripngd
Do not build ripngd.
--disable-ospfd
Do not build ospfd.
--disable-ospf6d
Do not build ospf6d.
--disable-bgpd
Do not build bgpd.
--disable-bgp-announce
Make bgpd which does not make bgp announcements at all. This feature is good for using bgpd as a BGP announcement listener.
--enable-netlink
Force to enable gnu/Linux netlink interface. Quagga configure script detects netlink interface by checking a header file. When the header file does not match to the current running kernel, configure script will not turn on netlink support.
--enable-snmp
Enable SNMP support. By default, SNMP support is disabled.
--enable-opaque-lsa
Enable support for Opaque LSAs (RFC2370) in ospfd.
--disable-ospfapi
Disable support for OSPF-API, an API to interface directly with ospfd. OSPF-API is enabled if –enable-opaque-lsa is set.
--disable-ospfclient
Disable building of the example OSPF-API client.
--enable-ospf-te
Enable support for OSPF Traffic Engineering Extension (internet-draft) this requires support for Opaque LSAs.
--enable-multipath=ARG
Enable support for Equal Cost Multipath. ARG is the maximum number of ECMP paths to allow, set to 0 to allow unlimited number of paths.
--enable-rtadv
Enable support IPV6 router advertisement in zebra.

You may specify any combination of the above options to the configure script. By default, the executables are placed in /usr/local/sbin and the configuration files in /usr/local/etc. The /usr/local/ installation prefix and other directories may be changed using the following options to the configuration script.

--prefix=prefix
Install architecture-independent files in prefix [/usr/local].
--sysconfdir=dir
Look for configuration files in dir [prefix/etc]. Note that sample configuration files will be installed here.
--localstatedir=dir
Configure zebra to use dir for local state files, such as pid files and unix sockets.
     % ./configure --disable-ipv6

This command will configure zebra and the routing daemons.


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2.1.2 Least-Privilege support

Additionally, you may configure zebra to drop its elevated privileges shortly after startup and switch to another user. The configure script will automatically try to configure this support. There are three configure options to control the behaviour of Quagga daemons.

--enable-user=user
Switch to user ARG shortly after startup, and run as user ARG in normal operation.
--enable-group=group
Switch real and effective group to group shortly after startup.
--enable-vty-group=group
Create Unix Vty sockets (for use with vtysh) with group owndership set to group. This allows one to create a seperate group which is restricted to accessing only the Vty sockets, hence allowing one to delegate this group to individual users, or to run vtysh setgid to this group.

The default user and group which will be configured is 'quagga' if no user or group is specified. Note that this user or group requires write access to the local state directory (see –localstatedir) and requires at least read access, and write access if you wish to allow daemons to write out their configuration, to the configuration directory (see –sysconfdir).

On systems which have the 'libcap' capabilities manipulation library (currently only linux), the quagga system will retain only minimal capabilities required, further it will only raise these capabilities for brief periods. On systems without libcap, quagga will run as the user specified and only raise its uid back to uid 0 for brief periods.


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2.1.3 Linux Notes

There are several options available only to gnu/Linux systems: 1. If you use gnu/Linux, make sure that the current kernel configuration is what you want. Quagga will run with any kernel configuration but some recommendations do exist.

CONFIG_NETLINK
Kernel/User netlink socket. This is a brand new feature which enables an advanced interface between the Linux kernel and zebra (see Kernel Interface).
CONFIG_RTNETLINK
Routing messages. This makes it possible to receive netlink routing messages. If you specify this option, zebra can detect routing information updates directly from the kernel (see Kernel Interface).
CONFIG_IP_MULTICAST
IP: multicasting. This option should be specified when you use ripd (see RIP) or ospfd (see OSPFv2) because these protocols use multicast.

IPv6 support has been added in gnu/Linux kernel version 2.2. If you try to use the Quagga IPv6 feature on a gnu/Linux kernel, please make sure the following libraries have been installed. Please note that these libraries will not be needed when you uses gnu C library 2.1 or upper.

inet6-apps
The inet6-apps package includes basic IPv6 related libraries such as inet_ntop and inet_pton. Some basic IPv6 programs such as ping, ftp, and inetd are also included. The inet-apps can be found at ftp://ftp.inner.net/pub/ipv6/.
net-tools
The net-tools package provides an IPv6 enabled interface and routing utility. It contains ifconfig, route, netstat, and other tools. net-tools may be found at http://www.tazenda.demon.co.uk/phil/net-tools/.


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2.2 Build the Software

After configuring the software, you will need to compile it for your system. Simply issue the command make in the root of the source directory and the software will be compiled. If you have *any* problems at this stage, be certain to send a bug report See Bug Reports.

     % ./configure
     .
     .
     .
     ./configure output
     .
     .
     .
     % make


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2.3 Install the Software

Installing the software to your system consists of copying the compiled programs and supporting files to a standard location. After the installation process has completed, these files have been copied from your work directory to /usr/local/bin, and /usr/local/etc.

To install the Quagga suite, issue the following command at your shell prompt: make install.

     %
     % make install
     %

Quagga daemons have their own terminal interface or VTY. After installation, you have to setup each beast's port number to connect to them. Please add the following entries to /etc/services.

     zebrasrv      2600/tcp		  # zebra service
     zebra         2601/tcp		  # zebra vty
     ripd          2602/tcp		  # RIPd vty
     ripngd        2603/tcp		  # RIPngd vty
     ospfd         2604/tcp		  # OSPFd vty
     bgpd          2605/tcp		  # BGPd vty
     ospf6d        2606/tcp		  # OSPF6d vty
     ospfapi       2607/tcp		  # ospfapi
     isisd         2608/tcp		  # ISISd vty

If you use a FreeBSD newer than 2.2.8, the above entries are already added to /etc/services so there is no need to add it. If you specify a port number when starting the daemon, these entries may not be needed.

You may need to make changes to the config files in /etc/quagga/*.conf. See Config Commands.


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3 Basic commands

There are five routing daemons in use, and there is one manager daemon. These daemons may be located on separate machines from the manager daemon. Each of these daemons will listen on a particular port for incoming VTY connections. The routing daemons are:

The following sections discuss commands common to all the routing daemons.


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3.1 Config Commands

In a config file, you can write the debugging options, a vty's password, routing daemon configurations, a log file name, and so forth. This information forms the initial command set for a routing beast as it is starting.

Config files are generally found in:

Each of the daemons has its own config file. For example, zebra's default config file name is:

The daemon name plus .conf is the default config file name. You can specify a config file using the -f or --config-file options when starting the daemon.


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3.1.1 Basic Config Commands

— Command: hostname hostname

Set hostname of the router.

— Command: password password

Set password for vty interface. If there is no password, a vty won't accept connections.

— Command: enable password password

Set enable password.

— Command: log trap level
— Command: no log trap

These commands are deprecated and are present only for historical compatibility. The log trap command sets the current logging level for all enabled logging destinations, and it sets the default for all future logging commands that do not specify a level. The normal default logging level is debugging. The no form of the command resets the default level for future logging commands to debugging, but it does not change the logging level of existing logging destinations.

— Command: log stdout
— Command: log stdout level
— Command: no log stdout

Enable logging output to stdout. If the optional second argument specifying the logging level is not present, the default logging level (typically debugging, but can be changed using the deprecated log trap command) will be used. The no form of the command disables logging to stdout. The level argument must have one of these values: emergencies, alerts, critical, errors, warnings, notifications, informational, or debugging. Note that the existing code logs its most important messages with severity errors.

— Command: log file filename
— Command: log file filename level
— Command: no log file

If you want to log into a file, please specify filename as in this example:

          log file /var/log/quagga/bgpd.log informational

If the optional second argument specifying the logging level is not present, the default logging level (typically debugging, but can be changed using the deprecated log trap command) will be used. The no form of the command disables logging to a file.

Note: if you do not configure any file logging, and a daemon crashes due to a signal or an assertion failure, it will attempt to save the crash information in a file named /var/tmp/quagga.<daemon name>.crashlog. For security reasons, this will not happen if the file exists already, so it is important to delete the file after reporting the crash information.

— Command: log syslog
— Command: log syslog level
— Command: no log syslog

Enable logging output to syslog. If the optional second argument specifying the logging level is not present, the default logging level (typically debugging, but can be changed using the deprecated log trap command) will be used. The no form of the command disables logging to syslog.

— Command: log monitor
— Command: log monitor level
— Command: no log monitor

Enable logging output to vty terminals that have enabled logging using the terminal monitor command. By default, monitor logging is enabled at the debugging level, but this command (or the deprecated log trap command) can be used to change the monitor logging level. If the optional second argument specifying the logging level is not present, the default logging level (typically debugging, but can be changed using the deprecated log trap command) will be used. The no form of the command disables logging to terminal monitors.

— Command: log facility facility
— Command: no log facility

This command changes the facility used in syslog messages. The default facility is daemon. The no form of the command resets the facility to the default daemon facility.

— Command: log record-priority
— Command: no log record-priority

To include the severity in all messages logged to a file, to stdout, or to a terminal monitor (i.e. anything except syslog), use the log record-priority global configuration command. To disable this option, use the no form of the command. By default, the severity level is not included in logged messages. Note: some versions of syslogd (including Solaris) can be configured to include the facility and level in the messages emitted.

— Command: log timestamp precision <0-6>
— Command: no log timestamp precision

This command sets the precision of log message timestamps to the given number of digits after the decimal point. Currently, the value must be in the range 0 to 6 (i.e. the maximum precision is microseconds). To restore the default behavior (1-second accuracy), use the no form of the command, or set the precision explicitly to 0.

          log timestamp precision 3

In this example, the precision is set to provide timestamps with millisecond accuracy.

— Command: service password-encryption

Encrypt password.

— Command: service advanced-vty

Enable advanced mode VTY.

— Command: service terminal-length <0-512>

Set system wide line configuration. This configuration command applies to all VTY interfaces.

— Command: line vty

Enter vty configuration mode.

— Command: banner motd default

Set default motd string.

— Command: no banner motd

No motd banner string will be printed.

— Line Command: exec-timeout minute
— Line Command: exec-timeout minute second

Set VTY connection timeout value. When only one argument is specified it is used for timeout value in minutes. Optional second argument is used for timeout value in seconds. Default timeout value is 10 minutes. When timeout value is zero, it means no timeout.

— Line Command: no exec-timeout

Do not perform timeout at all. This command is as same as exec-timeout 0 0.

— Line Command: access-class access-list

Restrict vty connections with an access list.


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3.1.2 Sample Config File

Below is a sample configuration file for the zebra daemon.

     !
     ! Zebra configuration file
     !
     hostname Router
     password zebra
     enable password zebra
     !
     log stdout
     !
     !

'!' and '#' are comment characters. If the first character of the word is one of the comment characters then from the rest of the line forward will be ignored as a comment.

     password zebra!password

If a comment character is not the first character of the word, it's a normal character. So in the above example '!' will not be regarded as a comment and the password is set to 'zebra!password'.


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3.2 Terminal Mode Commands

— Command: write terminal

Displays the current configuration to the vty interface.

— Command: write file

Write current configuration to configuration file.

— Command: configure terminal

Change to configuration mode. This command is the first step to configuration.

— Command: terminal length <0-512>

Set terminal display length to <0-512>. If length is 0, no display control is performed.

— Command: who

Show a list of currently connected vty sessions.

— Command: list

List all available commands.

— Command: show version

Show the current version of Quagga and its build host information.

— Command: show logging

Shows the current configuration of the logging system. This includes the status of all logging destinations.

— Command: logmsg level message

Send a message to all logging destinations that are enabled for messages of the given severity.


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3.3 Common Invocation Options

These options apply to all Quagga daemons.

-d
--daemon
Runs in daemon mode.
-f file
--config_file=file
Set configuration file name.
-h
--help
Display this help and exit.
-i file
--pid_file=file
Upon startup the process identifier of the daemon is written to a file, typically in /var/run. This file can be used by the init system to implement commands such as .../init.d/zebra status, .../init.d/zebra restart or .../init.d/zebra stop.

The file name is an run-time option rather than a configure-time option so that multiple routing daemons can be run simultaneously. This is useful when using Quagga to implement a routing looking glass. One machine can be used to collect differing routing views from differing points in the network.

-A address
--vty_addr=address
Set the VTY local address to bind to. If set, the VTY socket will only be bound to this address.
-P port
--vty_port=port
Set the VTY TCP port number. If set to 0 then the TCP VTY sockets will not be opened.
-u user
--vty_addr=user
Set the user and group to run as.
-v
--version
Print program version.


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3.4 Virtual Terminal Interfaces

VTY – Virtual Terminal [aka TeletYpe] Interface is a command line interface (CLI) for user interaction with the routing daemon.


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3.4.1 VTY Overview

VTY stands for Virtual TeletYpe interface. It means you can connect to the daemon via the telnet protocol.

To enable a VTY interface, you have to setup a VTY password. If there is no VTY password, one cannot connect to the VTY interface at all.

     % telnet localhost 2601
     Trying 127.0.0.1...
     Connected to localhost.
     Escape character is '^]'.
     
     Hello, this is Quagga (version 0.99.17.6)
     Copyright © 1999-2005 Kunihiro Ishiguro, et al.
     
     User Access Verification
     
     Password: XXXXX
     Router> ?
       enable            Turn on privileged commands
       exit              Exit current mode and down to previous mode
       help              Description of the interactive help system
       list              Print command list
       show              Show running system information
       who               Display who is on a vty
     Router> enable
     Password: XXXXX
     Router# configure terminal
     Router(config)# interface eth0
     Router(config-if)# ip address 10.0.0.1/8
     Router(config-if)# ^Z
     Router#

'?' is very useful for looking up commands.


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3.4.2 VTY Modes

There are three basic VTY modes:

There are commands that may be restricted to specific VTY modes.


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3.4.2.1 VTY View Mode

This mode is for read-only access to the CLI. One may exit the mode by leaving the system, or by entering enable mode.


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3.4.2.2 VTY Enable Mode

This mode is for read-write access to the CLI. One may exit the mode by leaving the system, or by escaping to view mode.


Previous: VTY Enable Mode, Up: VTY Modes
3.4.2.3 VTY Other Modes

This page is for describing other modes.


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3.4.3 VTY CLI Commands

Commands that you may use at the command-line are described in the following three subsubsections.


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3.4.3.1 CLI Movement Commands

These commands are used for moving the CLI cursor. The <C> character means press the Control Key.

C-f
<RIGHT>
Move forward one character.
C-b
<LEFT>
Move backward one character.
M-f
Move forward one word.
M-b
Move backward one word.
C-a
Move to the beginning of the line.
C-e
Move to the end of the line.


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3.4.3.2 CLI Editing Commands

These commands are used for editing text on a line. The <C> character means press the Control Key.

C-h
<DEL>
Delete the character before point.
C-d
Delete the character after point.
M-d
Forward kill word.
C-w
Backward kill word.
C-k
Kill to the end of the line.
C-u
Kill line from the beginning, erasing input.
C-t
Transpose character.


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3.4.3.3 CLI Advanced Commands

There are several additional CLI commands for command line completions, insta-help, and VTY session management.

C-c
Interrupt current input and moves to the next line.
C-z
End current configuration session and move to top node.
C-n
<DOWN>
Move down to next line in the history buffer.
C-p
<UP>
Move up to previous line in the history buffer.
TAB
Use command line completion by typing <TAB>.
You can use command line help by typing help at the beginning of the line. Typing ? at any point in the line will show possible completions.


Next: , Previous: Basic commands, Up: Top

4 Zebra

zebra is an IP routing manager. It provides kernel routing table updates, interface lookups, and redistribution of routes between different routing protocols.


Next: , Up: Zebra

4.1 Invoking zebra

Besides the common invocation options (see Common Invocation Options), the zebra specific invocation options are listed below.

-b
--batch
Runs in batch mode. zebra parses configuration file and terminates immediately.
-k
--keep_kernel
When zebra starts up, don't delete old self inserted routes.
-r
--retain
When program terminates, retain routes added by zebra.


Next: , Previous: Invoking zebra, Up: Zebra

4.2 Interface Commands

— Command: interface ifname
— Interface Command: shutdown
— Interface Command: no shutdown

Up or down the current interface.

— Interface Command: ip address address/prefix
— Interface Command: ipv6 address address/prefix
— Interface Command: no ip address address/prefix
— Interface Command: no ipv6 address address/prefix

Set the IPv4 or IPv6 address/prefix for the interface.

— Interface Command: ip address address/prefix secondary
— Interface Command: no ip address address/prefix secondary

Set the secondary flag for this address. This causes ospfd to not treat the address as a distinct subnet.

— Interface Command: description description ...

Set description for the interface.

— Interface Command: multicast
— Interface Command: no multicast

Enable or disables multicast flag for the interface.

— Interface Command: bandwidth <1-10000000>
— Interface Command: no bandwidth <1-10000000>

Set bandwidth value of the interface in kilobits/sec. This is for calculating OSPF cost. This command does not affect the actual device configuration.

— Interface Command: link-detect
— Interface Command: no link-detect

Enable/disable link-detect on platforms which support this. Currently only Linux, and only where network interface drivers support reporting link-state via the IFF_RUNNING flag.


Next: , Previous: Interface Commands, Up: Zebra

4.3 Static Route Commands

Static routing is a very fundamental feature of routing technology. It defines static prefix and gateway.

— Command: ip route network gateway

network is destination prefix with format of A.B.C.D/M. gateway is gateway for the prefix. When gateway is A.B.C.D format. It is taken as a IPv4 address gateway. Otherwise it is treated as an interface name. If the interface name is null0 then zebra installs a blackhole route.

          ip route 10.0.0.0/8 10.0.0.2
          ip route 10.0.0.0/8 ppp0
          ip route 10.0.0.0/8 null0

First example defines 10.0.0.0/8 static route with gateway 10.0.0.2. Second one defines the same prefix but with gateway to interface ppp0. The third install a blackhole route.

— Command: ip route network netmask gateway

This is alternate version of above command. When network is A.B.C.D format, user must define netmask value with A.B.C.D format. gateway is same option as above command

          ip route 10.0.0.0 255.255.255.0 10.0.0.2
          ip route 10.0.0.0 255.255.255.0 ppp0
          ip route 10.0.0.0 255.255.255.0 null0

These statements are equivalent to those in the previous example.

— Command: ip route network gateway distance

Installs the route with the specified distance.

Multiple nexthop static route

     ip route 10.0.0.1/32 10.0.0.2
     ip route 10.0.0.1/32 10.0.0.3
     ip route 10.0.0.1/32 eth0

If there is no route to 10.0.0.2 and 10.0.0.3, and interface eth0 is reachable, then the last route is installed into the kernel.

If zebra has been compiled with multipath support, and both 10.0.0.2 and 10.0.0.3 are reachable, zebra will install a multipath route via both nexthops, if the platform supports this.

     zebra> show ip route
     S>  10.0.0.1/32 [1/0] via 10.0.0.2 inactive
                           via 10.0.0.3 inactive
       *                   is directly connected, eth0
     ip route 10.0.0.0/8 10.0.0.2
     ip route 10.0.0.0/8 10.0.0.3
     ip route 10.0.0.0/8 null0 255

This will install a multihop route via the specified next-hops if they are reachable, as well as a high-metric blackhole route, which can be useful to prevent traffic destined for a prefix to match less-specific routes (eg default) should the specified gateways not be reachable. Eg:

     zebra> show ip route 10.0.0.0/8
     Routing entry for 10.0.0.0/8
       Known via "static", distance 1, metric 0
         10.0.0.2 inactive
         10.0.0.3 inactive
     
     Routing entry for 10.0.0.0/8
       Known via "static", distance 255, metric 0
         directly connected, Null0
— Command: ipv6 route network gateway
— Command: ipv6 route network gateway distance

These behave similarly to their ipv4 counterparts.

— Command: table tableno

Select the primary kernel routing table to be used. This only works for kernels supporting multiple routing tables (like GNU/Linux 2.2.x and later). After setting tableno with this command, static routes defined after this are added to the specified table.


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4.4 zebra Route Filtering

Zebra supports prefix-list and route-map to match routes received from other quagga components. The permit/deny facilities provided by these commands can be used to filter which routes zebra will install in the kernel.

— Command: ip protocol protocol route-map routemap

Apply a route-map filter to routes for the specified protocol. protocol can be any or one of system, kernel, connected, static, rip, ripng, ospf, ospf6, isis, bgp, hsls.

— Route Map: set src address

Within a route-map, set the preferred source address for matching routes when installing in the kernel.

     The following creates a prefix-list that matches all addresses, a route-map
     that sets the preferred source address, and applies the route-map to all
     rip routes.
     
     ip prefix-list ANY permit 0.0.0.0/0 le 32
     route-map RM1 permit 10
          match ip address prefix-list ANY
          set src 10.0.0.1
     
     ip protocol rip route-map RM1


Previous: zebra Route Filtering, Up: Zebra

4.5 zebra Terminal Mode Commands

— Command: show ip route

Display current routes which zebra holds in its database.

          Router# show ip route
          Codes: K - kernel route, C - connected, S - static, R - RIP,
                 B - BGP * - FIB route.
          
          K* 0.0.0.0/0              203.181.89.241
          S  0.0.0.0/0              203.181.89.1
          C* 127.0.0.0/8            lo
          C* 203.181.89.240/28      eth0
— Command: show ipv6 route
— Command: show interface
— Command: show ip prefix-list [name]
— Command: show route-map [name]
— Command: show ip protocol
— Command: show ipforward

Display whether the host's IP forwarding function is enabled or not. Almost any UNIX kernel can be configured with IP forwarding disabled. If so, the box can't work as a router.

— Command: show ipv6forward

Display whether the host's IP v6 forwarding is enabled or not.


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5 RIP

RIP – Routing Information Protocol is widely deployed interior gateway protocol. RIP was developed in the 1970s at Xerox Labs as part of the XNS routing protocol. RIP is a distance-vector protocol and is based on the Bellman-Ford algorithms. As a distance-vector protocol, RIP router send updates to its neighbors periodically, thus allowing the convergence to a known topology. In each update, the distance to any given network will be broadcasted to its neighboring router.

ripd supports RIP version 2 as described in RFC2453 and RIP version 1 as described in RFC1058.


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5.1 Starting and Stopping ripd

The default configuration file name of ripd's is ripd.conf. When invocation ripd searches directory /etc/quagga. If ripd.conf is not there next search current directory.

RIP uses UDP port 520 to send and receive RIP packets. So the user must have the capability to bind the port, generally this means that the user must have superuser privileges. RIP protocol requires interface information maintained by zebra daemon. So running zebra is mandatory to run ripd. Thus minimum sequence for running RIP is like below:

     # zebra -d
     # ripd -d

Please note that zebra must be invoked before ripd.

To stop ripd. Please use kill `cat /var/run/ripd.pid`. Certain signals have special meaningss to ripd.

SIGHUP
Reload configuration file ripd.conf. All configurations are reseted. All routes learned so far are cleared and removed from routing table.
SIGUSR1
Rotate ripd logfile.
SIGINT
SIGTERM
ripd sweeps all installed RIP routes then terminates properly.

ripd invocation options. Common options that can be specified (see Common Invocation Options).

-r
--retain
When the program terminates, retain routes added by ripd.


Up: Starting and Stopping ripd

5.1.1 RIP netmask

The netmask features of ripd support both version 1 and version 2 of RIP. Version 1 of RIP originally contained no netmask information. In RIP version 1, network classes were originally used to determine the size of the netmask. Class A networks use 8 bits of mask, Class B networks use 16 bits of masks, while Class C networks use 24 bits of mask. Today, the most widely used method of a network mask is assigned to the packet on the basis of the interface that received the packet. Version 2 of RIP supports a variable length subnet mask (VLSM). By extending the subnet mask, the mask can be divided and reused. Each subnet can be used for different purposes such as large to middle size LANs and WAN links. Quagga ripd does not support the non-sequential netmasks that are included in RIP Version 2.

In a case of similar information with the same prefix and metric, the old information will be suppressed. Ripd does not currently support equal cost multipath routing.


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5.2 RIP Configuration

— Command: router rip

The router rip command is necessary to enable RIP. To disable RIP, use the no router rip command. RIP must be enabled before carrying out any of the RIP commands.

— Command: no router rip

Disable RIP.

— RIP Command: network network
— RIP Command: no network network

Set the RIP enable interface by network. The interfaces which have addresses matching with network are enabled.

This group of commands either enables or disables RIP interfaces between certain numbers of a specified network address. For example, if the network for 10.0.0.0/24 is RIP enabled, this would result in all the addresses from 10.0.0.0 to 10.0.0.255 being enabled for RIP. The no network command will disable RIP for the specified network.

— RIP Command: network ifname
— RIP Command: no network ifname

Set a RIP enabled interface by ifname. Both the sending and receiving of RIP packets will be enabled on the port specified in the network ifname command. The no network ifname command will disable RIP on the specified interface.

— RIP Command: neighbor a.b.c.d
— RIP Command: no neighbor a.b.c.d

Specify RIP neighbor. When a neighbor doesn't understand multicast, this command is used to specify neighbors. In some cases, not all routers will be able to understand multicasting, where packets are sent to a network or a group of addresses. In a situation where a neighbor cannot process multicast packets, it is necessary to establish a direct link between routers. The neighbor command allows the network administrator to specify a router as a RIP neighbor. The no neighbor a.b.c.d command will disable the RIP neighbor.

Below is very simple RIP configuration. Interface eth0 and interface which address match to 10.0.0.0/8 are RIP enabled.

     !
     router rip
      network 10.0.0.0/8
      network eth0
     !

Passive interface

— RIP command: passive-interface (IFNAME|default)
— RIP command: no passive-interface IFNAME

This command sets the specified interface to passive mode. On passive mode interface, all receiving packets are processed as normal and ripd does not send either multicast or unicast RIP packets except to RIP neighbors specified with neighbor command. The interface may be specified as default to make ripd default to passive on all interfaces.

The default is to be passive on all interfaces.

RIP split-horizon

— Interface command: ip split-horizon
— Interface command: no ip split-horizon

Control split-horizon on the interface. Default is ip split-horizon. If you don't perform split-horizon on the interface, please specify no ip split-horizon.


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5.3 RIP Version Control

RIP can be configured to send either Version 1 or Version 2 packets. The default is to send RIPv2 while accepting both RIPv1 and RIPv2 (and replying with packets of the appropriate version for REQUESTS / triggered updates). The version to receive and send can be specified globally, and further overriden on a per-interface basis if needs be for send and receive seperately (see below).

It is important to note that RIPv1 can not be authenticated. Further, if RIPv1 is enabled then RIP will reply to REQUEST packets, sending the state of its RIP routing table to any remote routers that ask on demand. For a more detailed discussion on the security implications of RIPv1 see RIP Authentication.

— RIP Command: version version

Set RIP version to accept for reads and send. version can be either `1” or `2”.

Disabling RIPv1 by specifying version 2 is STRONGLY encouraged, See RIP Authentication. This may become the default in a future release.

Default: Send Version 2, and accept either version.

— RIP Command: no version

Reset the global version setting back to the default.

— Interface command: ip rip send version version

version can be `1', `2' or `1 2'.

This interface command overrides the global rip version setting, and selects which version of RIP to send packets with, for this interface specifically. Choice of RIP Version 1, RIP Version 2, or both versions. In the latter case, where `1 2' is specified, packets will be both broadcast and multicast.

Default: Send packets according to the global version (version 2)

— Interface command: ip rip receive version version

version can be `1', `2' or `1 2'.

This interface command overrides the global rip version setting, and selects which versions of RIP packets will be accepted on this interface. Choice of RIP Version 1, RIP Version 2, or both.

Default: Accept packets according to the global setting (both 1 and 2).


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5.4 How to Announce RIP route

— RIP command: redistribute kernel
— RIP command: redistribute kernel metric <0-16>
— RIP command: redistribute kernel route-map route-map
— RIP command: no redistribute kernel

redistribute kernel redistributes routing information from kernel route entries into the RIP tables. no redistribute kernel disables the routes.

— RIP command: redistribute static
— RIP command: redistribute static metric <0-16>
— RIP command: redistribute static route-map route-map
— RIP command: no redistribute static

redistribute static redistributes routing information from static route entries into the RIP tables. no redistribute static disables the routes.

— RIP command: redistribute connected
— RIP command: redistribute connected metric <0-16>
— RIP command: redistribute connected route-map route-map
— RIP command: no redistribute connected

Redistribute connected routes into the RIP tables. no redistribute connected disables the connected routes in the RIP tables. This command redistribute connected of the interface which RIP disabled. The connected route on RIP enabled interface is announced by default.

— RIP command: redistribute ospf
— RIP command: redistribute ospf metric <0-16>
— RIP command: redistribute ospf route-map route-map
— RIP command: no redistribute ospf

redistribute ospf redistributes routing information from ospf route entries into the RIP tables. no redistribute ospf disables the routes.

— RIP command: redistribute bgp
— RIP command: redistribute bgp metric <0-16>
— RIP command: redistribute bgp route-map route-map
— RIP command: no redistribute bgp

redistribute bgp redistributes routing information from bgp route entries into the RIP tables. no redistribute bgp disables the routes.

If you want to specify RIP only static routes:

— RIP command: default-information originate
— RIP command: route a.b.c.d/m
— RIP command: no route a.b.c.d/m

This command is specific to Quagga. The route command makes a static route only inside RIP. This command should be used only by advanced users who are particularly knowledgeable about the RIP protocol. In most cases, we recommend creating a static route in Quagga and redistributing it in RIP using redistribute static.


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5.5 Filtering RIP Routes

RIP routes can be filtered by a distribute-list.

— Command: distribute-list access_list direct ifname

You can apply access lists to the interface with a distribute-list command. access_list is the access list name. direct is ‘in’ or ‘out’. If direct is ‘in’ the access list is applied to input packets.

The distribute-list command can be used to filter the RIP path. distribute-list can apply access-lists to a chosen interface. First, one should specify the access-list. Next, the name of the access-list is used in the distribute-list command. For example, in the following configuration ‘eth0’ will permit only the paths that match the route 10.0.0.0/8

          !
          router rip
           distribute-list private in eth0
          !
          access-list private permit 10 10.0.0.0/8
          access-list private deny any
          !

distribute-list can be applied to both incoming and outgoing data.

— Command: distribute-list prefix prefix_list (in|out) ifname

You can apply prefix lists to the interface with a distribute-list command. prefix_list is the prefix list name. Next is the direction of ‘in’ or ‘out’. If direct is ‘in’ the access list is applied to input packets.


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5.6 RIP Metric Manipulation

RIP metric is a value for distance for the network. Usually ripd increment the metric when the network information is received. Redistributed routes' metric is set to 1.

— RIP command: default-metric <1-16>
— RIP command: no default-metric <1-16>

This command modifies the default metric value for redistributed routes. The default value is 1. This command does not affect connected route even if it is redistributed by redistribute connected. To modify connected route's metric value, please use redistribute connected metric or route-map. offset-list also affects connected routes.

— RIP command: offset-list access-list (in|out)
— RIP command: offset-list access-list (in|out) ifname


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5.7 RIP distance

Distance value is used in zebra daemon. Default RIP distance is 120.

— RIP command: distance <1-255>
— RIP command: no distance <1-255>

Set default RIP distance to specified value.

— RIP command: distance <1-255> A.B.C.D/M
— RIP command: no distance <1-255> A.B.C.D/M

Set default RIP distance to specified value when the route's source IP address matches the specified prefix.

— RIP command: distance <1-255> A.B.C.D/M access-list
— RIP command: no distance <1-255> A.B.C.D/M access-list

Set default RIP distance to specified value when the route's source IP address matches the specified prefix and the specified access-list.


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5.8 RIP route-map

Usage of ripd's route-map support.

Optional argument route-map MAP_NAME can be added to each redistribute statement.

     redistribute static [route-map MAP_NAME]
     redistribute connected [route-map MAP_NAME]
     .....

Cisco applies route-map _before_ routes will exported to rip route table. In current Quagga's test implementation, ripd applies route-map after routes are listed in the route table and before routes will be announced to an interface (something like output filter). I think it is not so clear, but it is draft and it may be changed at future.

Route-map statement (see Route Map) is needed to use route-map functionality.

— Route Map: match interface word

This command match to incoming interface. Notation of this match is different from Cisco. Cisco uses a list of interfaces - NAME1 NAME2 ... NAMEN. Ripd allows only one name (maybe will change in the future). Next - Cisco means interface which includes next-hop of routes (it is somewhat similar to "ip next-hop" statement). Ripd means interface where this route will be sent. This difference is because "next-hop" of same routes which sends to different interfaces must be different. Maybe it'd be better to made new matches - say "match interface-out NAME" or something like that.

— Route Map: match ip address word
— Route Map: match ip address prefix-list word

Match if route destination is permitted by access-list.

— Route Map: match ip next-hop word
— Route Map: match ip next-hop prefix-list word

Match if route next-hop (meaning next-hop listed in the rip route-table as displayed by "show ip rip") is permitted by access-list.

— Route Map: match metric <0-4294967295>

This command match to the metric value of RIP updates. For other protocol compatibility metric range is shown as <0-4294967295>. But for RIP protocol only the value range <0-16> make sense.

— Route Map: set ip next-hop A.B.C.D

This command set next hop value in RIPv2 protocol. This command does not affect RIPv1 because there is no next hop field in the packet.

— Route Map: set metric <0-4294967295>

Set a metric for matched route when sending announcement. The metric value range is very large for compatibility with other protocols. For RIP, valid metric values are from 1 to 16.


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5.9 RIP Authentication

RIPv2 allows packets to be authenticated via either an insecure plain text password, included with the packet, or via a more secure MD5 based HMAC (keyed-Hashing for Message AuthentiCation), RIPv1 can not be authenticated at all, thus when authentication is configured ripd will discard routing updates received via RIPv1 packets.

However, unless RIPv1 reception is disabled entirely, See RIP Version Control, RIPv1 REQUEST packets which are received, which query the router for routing information, will still be honoured by ripd, and ripd WILL reply to such packets. This allows ripd to honour such REQUESTs (which sometimes is used by old equipment and very simple devices to bootstrap their default route), while still providing security for route updates which are received.

In short: Enabling authentication prevents routes being updated by unauthenticated remote routers, but still can allow routes (I.e. the entire RIP routing table) to be queried remotely, potentially by anyone on the internet, via RIPv1.

To prevent such unauthenticated querying of routes disable RIPv1, See RIP Version Control.

— Interface command: ip rip authentication mode md5
— Interface command: no ip rip authentication mode md5

Set the interface with RIPv2 MD5 authentication.

— Interface command: ip rip authentication mode text
— Interface command: no ip rip authentication mode text

Set the interface with RIPv2 simple password authentication.

— Interface command: ip rip authentication string string
— Interface command: no ip rip authentication string string

RIP version 2 has simple text authentication. This command sets authentication string. The string must be shorter than 16 characters.

— Interface command: ip rip authentication key-chain key-chain
— Interface command: no ip rip authentication key-chain key-chain

Specifiy Keyed MD5 chain.

     !
     key chain test
      key 1
       key-string test
     !
     interface eth1
      ip rip authentication mode md5
      ip rip authentication key-chain test
     !


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5.10 RIP Timers

— RIP command: timers basic update timeout garbage

RIP protocol has several timers. User can configure those timers' values by timers basic command.

The default settings for the timers are as follows:

The timers basic command allows the the default values of the timers listed above to be changed.

— RIP command: no timers basic

The no timers basic command will reset the timers to the default settings listed above.


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5.11 Show RIP Information

To display RIP routes.

— Command: show ip rip

Show RIP routes.

The command displays all RIP routes. For routes that are received through RIP, this command will display the time the packet was sent and the tag information. This command will also display this information for routes redistributed into RIP.

— Command: show ip protocols

The command displays current RIP status. It includes RIP timer, filtering, version, RIP enabled interface and RIP peer inforation.

     ripd> show ip protocols
     Routing Protocol is "rip"
       Sending updates every 30 seconds with +/-50%, next due in 35 seconds
       Timeout after 180 seconds, garbage collect after 120 seconds
       Outgoing update filter list for all interface is not set
       Incoming update filter list for all interface is not set
       Default redistribution metric is 1
       Redistributing: kernel connected
       Default version control: send version 2, receive version 2
         Interface        Send  Recv
       Routing for Networks:
         eth0
         eth1
         1.1.1.1
         203.181.89.241
       Routing Information Sources:
         Gateway          BadPackets BadRoutes  Distance Last Update


Previous: Show RIP Information, Up: RIP

5.12 RIP Debug Commands

Debug for RIP protocol.

— Command: debug rip events

Debug rip events.

debug rip will show RIP events. Sending and receiving packets, timers, and changes in interfaces are events shown with ripd.

— Command: debug rip packet

Debug rip packet.

debug rip packet will display detailed information about the RIP packets. The origin and port number of the packet as well as a packet dump is shown.

— Command: debug rip zebra

Debug rip between zebra communication.

This command will show the communication between ripd and zebra. The main information will include addition and deletion of paths to the kernel and the sending and receiving of interface information.

— Command: show debugging rip

Display ripd's debugging option.

show debugging rip will show all information currently set for ripd debug.


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6 RIPng

ripngd supports the RIPng protocol as described in RFC2080. It's an IPv6 reincarnation of the RIP protocol.


Next: , Up: RIPng

6.1 Invoking ripngd

There are no ripngd specific invocation options. Common options can be specified (see Common Invocation Options).


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6.2 ripngd Configuration

Currently ripngd supports the following commands:

— Command: router ripng

Enable RIPng.

— RIPng Command: flush_timer time

Set flush timer.

— RIPng Command: network network

Set RIPng enabled interface by network

— RIPng Command: network ifname

Set RIPng enabled interface by ifname

— RIPng Command: route network

Set RIPng static routing announcement of network.

— Command: router zebra

This command is the default and does not appear in the configuration. With this statement, RIPng routes go to the zebra daemon.


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6.3 ripngd Terminal Mode Commands

— Command: show ip ripng
— Command: show debugging ripng
— Command: debug ripng events
— Command: debug ripng packet
— Command: debug ripng zebra


Previous: ripngd Terminal Mode Commands, Up: RIPng

6.4 ripngd Filtering Commands

— Command: distribute-list access_list (in|out) ifname

You can apply an access-list to the interface using the distribute-list command. access_list is an access-list name. direct is ‘in’ or ‘out’. If direct is ‘in’, the access-list is applied only to incoming packets.

          distribute-list local-only out sit1


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7 OSPFv2

OSPF (Open Shortest Path First) version 2 is a routing protocol which is described in RFC2328, OSPF Version 2. OSPF is an IGP (Interior Gateway Protocol). Compared with RIP, OSPF can provide scalable network support and faster convergence times. OSPF is widely used in large networks such as ISP (Internet Service Provider) backbone and enterprise networks.


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7.1 Configuring ospfd

There are no ospfd specific options. Common options can be specified (see Common Invocation Options) to ospfd. ospfd needs to acquire interface information from zebra in order to function. Therefore zebra must be running before invoking ospfd. Also, if zebra is restarted then ospfd must be too.

Like other daemons, ospfd configuration is done in OSPF specific configuration file ospfd.conf.


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7.2 OSPF router

To start OSPF process you have to specify the OSPF router. As of this writing, ospfd does not support multiple OSPF processes.

— Command: router ospf
— Command: no router ospf

Enable or disable the OSPF process. ospfd does not yet support multiple OSPF processes. So you can not specify an OSPF process number.

— OSPF Command: ospf router-id a.b.c.d
— OSPF Command: no ospf router-id

This sets the router-ID of the OSPF process. The router-ID may be an IP address of the router, but need not be - it can be any arbitrary 32bit number. However it MUST be unique within the entire OSPF domain to the OSPF speaker - bad things will happen if multiple OSPF speakers are configured with the same router-ID! If one is not specified then ospfd will obtain a router-ID automatically from zebra.

— OSPF Command: ospf abr-type type
— OSPF Command: no ospf abr-type type

type can be cisco|ibm|shortcut|standard. The "Cisco" and "IBM" types are equivalent.

The OSPF standard for ABR behaviour does not allow an ABR to consider routes through non-backbone areas when its links to the backbone are down, even when there are other ABRs in attached non-backbone areas which still can reach the backbone - this restriction exists primarily to ensure routing-loops are avoided.

With the "Cisco" or "IBM" ABR type, the default in this release of Quagga, this restriction is lifted, allowing an ABR to consider summaries learnt from other ABRs through non-backbone areas, and hence route via non-backbone areas as a last resort when, and only when, backbone links are down.

Note that areas with fully-adjacent virtual-links are considered to be "transit capable" and can always be used to route backbone traffic, and hence are unaffected by this setting (see OSPF virtual-link).

More information regarding the behaviour controlled by this command can be found in RFC 3509, Alternative Implementations of OSPF Area Border Routers, and draft-ietf-ospf-shortcut-abr-02.txt.

Quote: "Though the definition of the ABR (Area Border Router) in the OSPF specification does not require a router with multiple attached areas to have a backbone connection, it is actually necessary to provide successful routing to the inter-area and external destinations. If this requirement is not met, all traffic destined for the areas not connected to such an ABR or out of the OSPF domain, is dropped. This document describes alternative ABR behaviors implemented in Cisco and IBM routers."

— OSPF Command: ospf rfc1583compatibility
— OSPF Command: no ospf rfc1583compatibility

RFC2328, the sucessor to RFC1583, suggests according to section G.2 (changes) in section 16.4 a change to the path preference algorithm that prevents possible routing loops that were possible in the old version of OSPFv2. More specifically it demands that inter-area paths and intra-area backbone path are now of equal preference but still both preferred to external paths.

This command should NOT be set normally.

— OSPF Command: log-adjacency-changes [detail]
— OSPF Command: no log-adjacency-changes [detail]

Configures ospfd to log changes in adjacency. With the optional detail argument, all changes in adjacency status are shown. Without detail, only changes to full or regressions are shown.

— OSPF Command: passive-interface interface
— OSPF Command: no passive-interface interface

Do not speak OSPF interface on the given interface, but do advertise the interface as a stub link in the router-LSA (Link State Advertisement) for this router. This allows one to advertise addresses on such connected interfaces without having to originate AS-External/Type-5 LSAs (which have global flooding scope) - as would occur if connected addresses were redistributed into OSPF (see Redistribute routes to OSPF). This is the only way to advertise non-OSPF links into stub areas.

— OSPF Command: timers throttle spf delay initial-holdtime max-holdtime
— OSPF Command: no timers throttle spf

This command sets the initial delay, the initial-holdtime and the maximum-holdtime between when SPF is calculated and the event which triggered the calculation. The times are specified in milliseconds and must be in the range of 0 to 600000 milliseconds.

The delay specifies the minimum amount of time to delay SPF calculation (hence it affects how long SPF calculation is delayed after an event which occurs outside of the holdtime of any previous SPF calculation, and also serves as a minimum holdtime).

Consecutive SPF calculations will always be seperated by at least 'hold-time' milliseconds. The hold-time is adaptive and initially is set to the initial-holdtime configured with the above command. Events which occur within the holdtime of the previous SPF calculation will cause the holdtime to be increased by initial-holdtime, bounded by the maximum-holdtime configured with this command. If the adaptive hold-time elapses without any SPF-triggering event occuring then the current holdtime is reset to the initial-holdtime. The current holdtime can be viewed with show ip ospf, where it is expressed as a multiplier of the initial-holdtime.

          router ospf
           timers throttle spf 200 400 10000

In this example, the delay is set to 200ms, the initial holdtime is set to 400ms and the maximum holdtime to 10s. Hence there will always be at least 200ms between an event which requires SPF calculation and the actual SPF calculation. Further consecutive SPF calculations will always be seperated by between 400ms to 10s, the hold-time increasing by 400ms each time an SPF-triggering event occurs within the hold-time of the previous SPF calculation.

This command supercedes the timers spf command in previous Quagga releases.

— OSPF Command: max-metric router-lsa [on-startup|on-shutdown] <5-86400>
— OSPF Command: max-metric router-lsa administrative
— OSPF Command: no max-metric router-lsa [on-startup|on-shutdown|administrative]

This enables RFC3137, OSPF Stub Router Advertisement support, where the OSPF process describes its transit links in its router-LSA as having infinite distance so that other routers will avoid calculating transit paths through the router while still being able to reach networks through the router.

This support may be enabled administratively (and indefinitely) or conditionally. Conditional enabling of max-metric router-lsas can be for a period of seconds after startup and/or for a period of seconds prior to shutdown.

Enabling this for a period after startup allows OSPF to converge fully first without affecting any existing routes used by other routers, while still allowing any connected stub links and/or redistributed routes to be reachable. Enabling this for a period of time in advance of shutdown allows the router to gracefully excuse itself from the OSPF domain.

Enabling this feature administratively allows for administrative intervention for whatever reason, for an indefinite period of time. Note that if the configuration is written to file, this administrative form of the stub-router command will also be written to file. If ospfd is restarted later, the command will then take effect until manually deconfigured.

Configured state of this feature as well as current status, such as the number of second remaining till on-startup or on-shutdown ends, can be viewed with the show ip ospf command.

— OSPF Command: auto-cost reference-bandwidth <1-4294967>
— OSPF Command: no auto-cost reference-bandwidth

This sets the reference bandwidth for cost calculations, where this bandwidth is considered equivalent to an OSPF cost of 1, specified in Mbits/s. The default is 100Mbit/s (i.e. a link of bandwidth 100Mbit/s or higher will have a cost of 1. Cost of lower bandwidth links will be scaled with reference to this cost).

This configuration setting MUST be consistent across all routers within the OSPF domain.

— OSPF Command: network a.b.c.d/m area a.b.c.d
— OSPF Command: network a.b.c.d/m area <0-4294967295>
— OSPF Command: no network a.b.c.d/m area a.b.c.d
— OSPF Command: no network a.b.c.d/m area <0-4294967295>

This command specifies the OSPF enabled interface(s). If the interface has an address from range 192.168.1.0/24 then the command below enables ospf on this interface so router can provide network information to the other ospf routers via this interface.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0

Prefix length in interface must be equal or bigger (ie. smaller network) than prefix length in network statement. For example statement above doesn't enable ospf on interface with address 192.168.1.1/23, but it does on interface with address 192.168.1.129/25.

Note that the behavior when there is a peer address defined on an interface changed after release 0.99.7. Currently, if a peer prefix has been configured, then we test whether the prefix in the network command contains the destination prefix. Otherwise, we test whether the network command prefix contains the local address prefix of the interface.


Next: , Previous: OSPF router, Up: OSPFv2

7.3 OSPF area

— OSPF Command: area a.b.c.d range a.b.c.d/m
— OSPF Command: area <0-4294967295> range a.b.c.d/m
— OSPF Command: no area a.b.c.d range a.b.c.d/m
— OSPF Command: no area <0-4294967295> range a.b.c.d/m

Summarize intra area paths from specified area into one Type-3 summary-LSA announced to other areas. This command can be used only in ABR and ONLY router-LSAs (Type-1) and network-LSAs (Type-2) (ie. LSAs with scope area) can be summarized. Type-5 AS-external-LSAs can't be summarized - their scope is AS. Summarizing Type-7 AS-external-LSAs isn't supported yet by Quagga.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0
           network 10.0.0.0/8 area 0.0.0.10
           area 0.0.0.10 range 10.0.0.0/8

With configuration above one Type-3 Summary-LSA with routing info 10.0.0.0/8 is announced into backbone area if area 0.0.0.10 contains at least one intra-area network (ie. described with router or network LSA) from this range.

— OSPF Command: area a.b.c.d range IPV4_PREFIX not-advertise
— OSPF Command: no area a.b.c.d range IPV4_PREFIX not-advertise

Instead of summarizing intra area paths filter them - ie. intra area paths from this range are not advertised into other areas. This command makes sense in ABR only.

— OSPF Command: area a.b.c.d range IPV4_PREFIX substitute IPV4_PREFIX
— OSPF Command: no area a.b.c.d range IPV4_PREFIX substitute IPV4_PREFIX

Substitute summarized prefix with another prefix.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0
           network 10.0.0.0/8 area 0.0.0.10
           area 0.0.0.10 range 10.0.0.0/8 substitute 11.0.0.0/8

One Type-3 summary-LSA with routing info 11.0.0.0/8 is announced into backbone area if area 0.0.0.10 contains at least one intra-area network (ie. described with router-LSA or network-LSA) from range 10.0.0.0/8. This command makes sense in ABR only.

— OSPF Command: area a.b.c.d virtual-link a.b.c.d
— OSPF Command: area <0-4294967295> virtual-link a.b.c.d
— OSPF Command: no area a.b.c.d virtual-link a.b.c.d
— OSPF Command: no area <0-4294967295> virtual-link a.b.c.d

— OSPF Command: area a.b.c.d shortcut
— OSPF Command: area <0-4294967295> shortcut
— OSPF Command: no area a.b.c.d shortcut
— OSPF Command: no area <0-4294967295> shortcut

Configure the area as Shortcut capable. See RFC3509. This requires that the 'abr-type' be set to 'shortcut'.

— OSPF Command: area a.b.c.d stub
— OSPF Command: area <0-4294967295> stub
— OSPF Command: no area a.b.c.d stub
— OSPF Command: no area <0-4294967295> stub

Configure the area to be a stub area. That is, an area where no router originates routes external to OSPF and hence an area where all external routes are via the ABR(s). Hence, ABRs for such an area do not need to pass AS-External LSAs (type-5s) or ASBR-Summary LSAs (type-4) into the area. They need only pass Network-Summary (type-3) LSAs into such an area, along with a default-route summary.

— OSPF Command: area a.b.c.d stub no-summary
— OSPF Command: area <0-4294967295> stub no-summary
— OSPF Command: no area a.b.c.d stub no-summary
— OSPF Command: no area <0-4294967295> stub no-summary

Prevents an ospfd ABR from injecting inter-area summaries into the specified stub area.

— OSPF Command: area a.b.c.d default-cost <0-16777215>
— OSPF Command: no area a.b.c.d default-cost <0-16777215>

Set the cost of default-summary LSAs announced to stubby areas.

— OSPF Command: area a.b.c.d export-list NAME
— OSPF Command: area <0-4294967295> export-list NAME
— OSPF Command: no area a.b.c.d export-list NAME
— OSPF Command: no area <0-4294967295> export-list NAME

Filter Type-3 summary-LSAs announced to other areas originated from intra- area paths from specified area.

          router ospf
           network 192.168.1.0/24 area 0.0.0.0
           network 10.0.0.0/8 area 0.0.0.10
           area 0.0.0.10 export-list foo
          !
          access-list foo permit 10.10.0.0/16
          access-list foo deny any

With example above any intra-area paths from area 0.0.0.10 and from range 10.10.0.0/16 (for example 10.10.1.0/24 and 10.10.2.128/30) are announced into other areas as Type-3 summary-LSA's, but any others (for example 10.11.0.0/16 or 10.128.30.16/30) aren't.

This command is only relevant if the router is an ABR for the specified area.

— OSPF Command: area a.b.c.d import-list NAME
— OSPF Command: area <0-4294967295> import-list NAME
— OSPF Command: no area a.b.c.d import-list NAME
— OSPF Command: no area <0-4294967295> import-list NAME

Same as export-list, but it applies to paths announced into specified area as Type-3 summary-LSAs.

— OSPF Command: area a.b.c.d filter-list prefix NAME in
— OSPF Command: area a.b.c.d filter-list prefix NAME out
— OSPF Command: area <0-4294967295> filter-list prefix NAME in
— OSPF Command: area <0-4294967295> filter-list prefix NAME out
— OSPF Command: no area a.b.c.d filter-list prefix NAME in
— OSPF Command: no area a.b.c.d filter-list prefix NAME out
— OSPF Command: no area <0-4294967295> filter-list prefix NAME in
— OSPF Command: no area <0-4294967295> filter-list prefix NAME out

Filtering Type-3 summary-LSAs to/from area using prefix lists. This command makes sense in ABR only.

— OSPF Command: area a.b.c.d authentication
— OSPF Command: area <0-4294967295> authentication
— OSPF Command: no area a.b.c.d authentication
— OSPF Command: no area <0-4294967295> authentication

Specify that simple password authentication should be used for the given area.

— OSPF Command: area a.b.c.d authentication message-digest
— OSPF Command: area <0-4294967295> authentication message-digest

Specify that OSPF packets must be authenticated with MD5 HMACs within the given area. Keying material must also be configured on a per-interface basis (see ip ospf message-digest-key).

MD5 authentication may also be configured on a per-interface basis (see ip ospf authentication message-digest). Such per-interface settings will override any per-area authentication setting.


Next: , Previous: OSPF area, Up: OSPFv2

7.4 OSPF interface

— Interface Command: ip ospf authentication-key AUTH_KEY
— Interface Command: no ip ospf authentication-key

Set OSPF authentication key to a simple password. After setting AUTH_KEY, all OSPF packets are authenticated. AUTH_KEY has length up to 8 chars.

Simple text password authentication is insecure and deprecated in favour of MD5 HMAC authentication (see ip ospf authentication message-digest).

— Interface Command: ip ospf authentication message-digest

Specify that MD5 HMAC authentication must be used on this interface. MD5 keying material must also be configured (see ip ospf message-digest-key). Overrides any authentication enabled on a per-area basis (see area authentication message-digest).

Note that OSPF MD5 authentication requires that time never go backwards (correct time is NOT important, only that it never goes backwards), even across resets, if ospfd is to be able to promptly reestabish adjacencies with its neighbours after restarts/reboots. The host should have system time be set at boot from an external or non-volatile source (eg battery backed clock, NTP, etc.) or else the system clock should be periodically saved to non-volative storage and restored at boot if MD5 authentication is to be expected to work reliably.

— Interface Command: ip ospf message-digest-key KEYID md5 KEY
— Interface Command: no ip ospf message-digest-key

Set OSPF authentication key to a cryptographic password. The cryptographic algorithm is MD5.

KEYID identifies secret key used to create the message digest. This ID is part of the protocol and must be consistent across routers on a link.

KEY is the actual message digest key, of up to 16 chars (larger strings will be truncated), and is associated with the given KEYID.

— Interface Command: ip ospf cost <1-65535>
— Interface Command: no ip ospf cost

Set link cost for the specified interface. The cost value is set to router-LSA's metric field and used for SPF calculation.

— Interface Command: ip ospf dead-interval <1-65535>
— Interface Command: ip ospf dead-interval minimal hello-multiplier <2-20>
— Interface Command: no ip ospf dead-interval

Set number of seconds for RouterDeadInterval timer value used for Wait Timer and Inactivity Timer. This value must be the same for all routers attached to a common network. The default value is 40 seconds.

If 'minimal' is specified instead, then the dead-interval is set to 1 second and one must specify a hello-multiplier. The hello-multiplier specifies how many Hellos to send per second, from 2 (every 500ms) to 20 (every 50ms). Thus one can have 1s convergence time for OSPF. If this form is specified, then the hello-interval advertised in Hello packets is set to 0 and the hello-interval on received Hello packets is not checked, thus the hello-multiplier need NOT be the same across multiple routers on a common link.

— Interface Command: ip ospf hello-interval <1-65535>
— Interface Command: no ip ospf hello-interval

Set number of seconds for HelloInterval timer value. Setting this value, Hello packet will be sent every timer value seconds on the specified interface. This value must be the same for all routers attached to a common network. The default value is 10 seconds.

This command has no effect if ip ospf dead-interval minimal is also specified for the interface.

— Interface Command: ip ospf network (broadcast|non-broadcast|point-to-multipoint|point-to-point)
— Interface Command: no ip ospf network

Set explicitly network type for specifed interface.

— Interface Command: ip ospf priority <0-255>
— Interface Command: no ip ospf priority

Set RouterPriority integer value. The router with the highest priority will be more eligible to become Designated Router. Setting the value to 0, makes the router ineligible to become Designated Router. The default value is 1.

— Interface Command: ip ospf retransmit-interval <1-65535>
— Interface Command: no ip ospf retransmit interval

Set number of seconds for RxmtInterval timer value. This value is used when retransmitting Database Description and Link State Request packets. The default value is 5 seconds.

— Interface Command: ip ospf transmit-delay
— Interface Command: no ip ospf transmit-delay

Set number of seconds for InfTransDelay value. LSAs' age should be incremented by this value when transmitting. The default value is 1 seconds.


Next: , Previous: OSPF interface, Up: OSPFv2

7.5 Redistribute routes to OSPF

— OSPF Command: redistribute (kernel|connected|static|rip|bgp)
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) route-map
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric-type (1|2)
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric-type (1|2) route-map word
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric <0-16777214>
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric <0-16777214> route-map word
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric-type (1|2) metric <0-16777214>
— OSPF Command: redistribute (kernel|connected|static|rip|bgp) metric-type (1|2) metric <0-16777214> route-map word
— OSPF Command: no redistribute (kernel|connected|static|rip|bgp)

Redistribute routes of the specified protocol or kind into OSPF, with the metric type and metric set if specified, filtering the routes using the given route-map if specified. Redistributed routes may also be filtered with distribute-lists, see ospf distribute-list.

Redistributed routes are distributed as into OSPF as Type-5 External LSAs into links to areas that accept external routes, Type-7 External LSAs for NSSA areas and are not redistributed at all into Stub areas, where external routes are not permitted.

Note that for connected routes, one may instead use passive-interface, see OSPF passive-interface.

— OSPF Command: default-information originate
— OSPF Command: default-information originate metric <0-16777214>
— OSPF Command: default-information originate metric <0-16777214> metric-type (1|2)
— OSPF Command: default-information originate metric <0-16777214> metric-type (1|2) route-map word
— OSPF Command: default-information originate always
— OSPF Command: default-information originate always metric <0-16777214>
— OSPF Command: default-information originate always metric <0-16777214> metric-type (1|2)
— OSPF Command: default-information originate always metric <0-16777214> metric-type (1|2) route-map word
— OSPF Command: no default-information originate

Originate an AS-External (type-5) LSA describing a default route into all external-routing capable areas, of the specified metric and metric type. If the 'always' keyword is given then the default is always advertised, even when there is no default present in the routing table.

— OSPF Command: distribute-list NAME out (kernel|connected|static|rip|ospf
— OSPF Command: no distribute-list NAME out (kernel|connected|static|rip|ospf

Apply the access-list filter, NAME, to redistributed routes of the given type before allowing the routes to redistributed into OSPF (see OSPF redistribute).

— OSPF Command: default-metric <0-16777214>
— OSPF Command: no default-metric
— OSPF Command: distance <1-255>
— OSPF Command: no distance <1-255>
— OSPF Command: distance ospf (intra-area|inter-area|external) <1-255>
— OSPF Command: no distance ospf
— OSPF Command: redistribute maximum-prefix HARDLIMIT
— OSPF Command: redistribute maximum-prefix HARDLIMIT SOFTLIMIT
— OSPF Command: redistribute maximum-prefix HARDLIMIT SOFTLIMIT warning-only
— OSPF Command: redistribute maximum-prefix HARDLIMIT warning-only
— OSPF Command: no redistribute maximum-prefix

Configure redistribution limits as requested. Hard limit is a number (1-4294967295) and has no default value (no limit applied). Soft limit is a percentage (1-99) threshold and has a default value of 75. Effective soft limit is taken as SOFTLIMIT percents of the HARDLIMIT value (with appropriate roundoff).

Once the soft limit is reached, a warning message is generated. As soon as the hard limit is reached, another warning message is generated and (unless "warning-only" option is explicitly requested) no further redistribution into OSPF happens. When the number of redistributed routes drops below the hard limit, redistribution begins working again.

This feature applies to Type-5 AS-External self-originated (redistributed) LSAs only. NSSA-translated LSAs are not counted in this process. The "no redistribute maximum-prefix" command may accept multiple arguments, but regardless of their values it always resets the limits to default (disabled).


Next: , Previous: Redistribute routes to OSPF, Up: OSPFv2

7.6 Showing OSPF information

— Command: show ip ospf

Show information on a variety of general OSPF and area state and configuration information.

— Command: show ip ospf interface [INTERFACE]

Show state and configuration of OSPF the specified interface, or all interfaces if no interface is given.

— Command: show ip ospf neighbor
— Command: show ip ospf neighbor INTERFACE
— Command: show ip ospf neighbor detail
— Command: show ip ospf neighbor INTERFACE detail
— Command: show ip ospf database
— Command: show ip ospf database (asbr-summary|external|network|router|summary)
— Command: show ip ospf database (asbr-summary|external|network|router|summary) link-state-id
— Command: show ip ospf database (asbr-summary|external|network|router|summary) link-state-id adv-router adv-router
— Command: show ip ospf database (asbr-summary|external|network|router|summary) adv-router adv-router
— Command: show ip ospf database (asbr-summary|external|network|router|summary) link-state-id self-originate
— Command: show ip ospf database (asbr-summary|external|network|router|summary) self-originate
— Command: show ip ospf database max-age
— Command: show ip ospf database self-originate
— Command: show ip ospf route

Show the OSPF routing table, as determined by the most recent SPF calculation.


Next: , Previous: Showing OSPF information, Up: OSPFv2

7.7 Debugging OSPF

— Command: debug ospf packet (hello|dd|ls-request|ls-update|ls-ack|all) (send|recv) [detail]
— Command: no debug ospf packet (hello|dd|ls-request|ls-update|ls-ack|all) (send|recv) [detail]
— Command: debug ospf ism
— Command: debug ospf ism (status|events|timers)
— Command: no debug ospf ism
— Command: no debug ospf ism (status|events|timers)
— Command: debug ospf nsm
— Command: debug ospf nsm (status|events|timers)
— Command: no debug ospf nsm
— Command: no debug ospf nsm (status|events|timers)
— Command: debug ospf lsa
— Command: debug ospf lsa (generate|flooding|refresh)
— Command: no debug ospf lsa
— Command: no debug ospf lsa (generate|flooding|refresh)
— Command: debug ospf zebra
— Command: debug ospf zebra (interface|redistribute)
— Command: no debug ospf zebra
— Command: no debug ospf zebra (interface|redistribute)
— Command: show debugging ospf


Previous: Debugging OSPF, Up: OSPFv2

7.8 OSPF Configuration Examples

A simple example, with MD5 authentication enabled:

     !
     interface bge0
      ip ospf authentication message-digest
      ip ospf message-digest-key 1 md5 ABCDEFGHIJK
     !
     router ospf
      network 192.168.0.0/16 area 0.0.0.1
      area 0.0.0.1 authentication message-digest

An ABR router, with MD5 authentication and performing summarisation of networks between the areas:

     !
     password ABCDEF
     log file /var/log/quagga/ospfd.log
     service advanced-vty
     !
     interface eth0
      ip ospf authentication message-digest
      ip ospf message-digest-key 1 md5 ABCDEFGHIJK
     !
     interface ppp0
     !
     interface br0
      ip ospf authentication message-digest
      ip ospf message-digest-key 2 md5 XYZ12345
     !
     router ospf
      ospf router-id 192.168.0.1
      redistribute connected
      passive interface ppp0
      network 192.168.0.0/24 area 0.0.0.0
      network 10.0.0.0/16 area 0.0.0.0
      network 192.168.1.0/24 area 0.0.0.1
      area 0.0.0.0 authentication message-digest
      area 0.0.0.0 range 10.0.0.0/16
      area 0.0.0.0 range 192.168.0.0/24
      area 0.0.0.1 authentication message-digest
      area 0.0.0.1 range 10.2.0.0/16
     !


Next: , Previous: OSPFv2, Up: Top

8 OSPFv3

ospf6d is a daemon support OSPF version 3 for IPv6 network. OSPF for IPv6 is described in RFC2740.


Next: , Up: OSPFv3

8.1 OSPF6 router

— Command: router ospf6
— OSPF6 Command: router-id a.b.c.d

Set router's Router-ID.

— OSPF6 Command: interface ifname area area

Bind interface to specified area, and start sending OSPF packets. area can be specified as 0.


Next: , Previous: OSPF6 router, Up: OSPFv3

8.2 OSPF6 area

Area support for OSPFv3 is not yet implemented.


Next: , Previous: OSPF6 area, Up: OSPFv3

8.3 OSPF6 interface

— Interface Command: ipv6 ospf6 cost COST

Sets interface's output cost. Default value is 1.

— Interface Command: ipv6 ospf6 hello-interval HELLOINTERVAL

Sets interface's Hello Interval. Default 40

— Interface Command: ipv6 ospf6 dead-interval DEADINTERVAL

Sets interface's Router Dead Interval. Default value is 40.

— Interface Command: ipv6 ospf6 retransmit-interval RETRANSMITINTERVAL

Sets interface's Rxmt Interval. Default value is 5.

— Interface Command: ipv6 ospf6 priority PRIORITY

Sets interface's Router Priority. Default value is 1.

— Interface Command: ipv6 ospf6 transmit-delay TRANSMITDELAY

Sets interface's Inf-Trans-Delay. Default value is 1.


Next: , Previous: OSPF6 interface, Up: OSPFv3

8.4 Redistribute routes to OSPF6

— OSPF6 Command: redistribute static
— OSPF6 Command: redistribute connected
— OSPF6 Command: redistribute ripng


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8.5 Showing OSPF6 information

— Command: show ipv6 ospf6 [INSTANCE_ID]

INSTANCE_ID is an optional OSPF instance ID. To see router ID and OSPF instance ID, simply type "show ipv6 ospf6 <cr>".

— Command: show ipv6 ospf6 database

This command shows LSA database summary. You can specify the type of LSA.

— Command: show ipv6 ospf6 interface

To see OSPF interface configuration like costs.

— Command: show ipv6 ospf6 neighbor

Shows state and chosen (Backup) DR of neighbor.

— Command: show ipv6 ospf6 request-list A.B.C.D

Shows requestlist of neighbor.

— Command: show ipv6 route ospf6

This command shows internal routing table.


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8.6 OSPF6 Configuration Examples

Example of ospf6d configured on one interface and area:

     interface eth0
      ipv6 ospf6 instance-id 0
     !
     router ospf6
      router-id 212.17.55.53
      area 0.0.0.0 range 2001:770:105:2::/64
      interface eth0 area 0.0.0.0
     !


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9 Babel

Babel is an interior gateway protocol that is suitable both for wired networks and for wireless mesh networks. Babel has been described as “RIP on speed” — it is based on the same principles as RIP, but includes a number of refinements that make it react much faster to topology changes without ever counting to infinity, and allow it to perform reliable link quality estimation on wireless links. Babel is a double-stack routing protocol, meaning that a single Babel instance is able to perform routing for both IPv4 and IPv6.

Quagga implements Babel as described in RFC6126.


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9.1 Configuring babeld

The babeld daemon can be invoked with any of the common options (see Common Invocation Options).

The zebra daemon must be running before babeld is invoked. Also, if zebra is restarted then babeld must be too.

Configuration of babeld is done in its configuration file babeld.conf.


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9.2 Babel configuration

— Command: router babel
— Command: no router babel

Enable or disable Babel routing.

— Babel Command: network ifname
— Babel Command: no network ifname

Enable or disable Babel on the given interface.

— Interface Command: babel wired
— Interface Command: babel wireless

Specifies whether this interface is wireless, which disables a number of optimisations that are only correct on wired interfaces. Specifying wireless (the default) is always correct, but may cause slower convergence and extra routing traffic.

— Interface Command: babel split-horizon
— Interface Command: no babel split-horizon

Specifies whether to perform split-horizon on the interface. Specifying no babel split-horizon (the default) is always correct, while babel split-horizon is an optimisation that should only be used on symmetric and transitive (wired) networks.

— Interface Command: babel passive-interface
— Interface Command: no babel passive-interface

Specifies whether this interface is passive. Note that this is a little weaker than RIP's notion of passive interface, since Babel always sends Hello packets and announces redistributed routes, even on passive interfaces.

— Interface Command: babel hello-interval <20-655340>

Specifies the time in milliseconds between two scheduled hellos. On wired links, Babel notices a link failure within two hello intervals; on wireless links, the link quality value is reestimated at every hello interval. The default is 4000ms.

— Interface Command: babel update-interval <20-655340>

Specifies the time in milliseconds between two scheduled updates. Since Babel makes extensive use of triggered updates, this can be set to fairly high values on links with little packet loss. The default is 20000ms.

— Babel Command: babel resend-delay <20-655340>

Specifies the time in milliseconds after which an “important” request or update will be resent. The default is 2000ms. You probably don't want to tweak this value.


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9.3 Babel redistribution

— Babel command: redistribute kind
— Babel command: no redistribute kind

Specify which kind of routes should be redistributed into Babel.


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9.4 Show Babel information

— Command: show babel database
— Command: show babel interface
— Command: show babel neighbour
— Command: show babel parameters

These commands dump various parts of babeld's internal state. They are mostly useful for troubleshooting.


Previous: Show Babel information, Up: Babel

9.5 Babel debugging commands

— Babel Command: debug babel kind
— Babel Command: no debug babel kind

Enable or disable debugging messages of a given kind. kind can be one of ‘common’, ‘kernel’, ‘filter’, ‘timeout’, ‘interface’, ‘route’ or ‘all’. Note that if you have compiled with the NO_DEBUG flag, then these commands aren't available.


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10 BGP

BGP stands for a Border Gateway Protocol. The lastest BGP version is 4. It is referred as BGP-4. BGP-4 is one of the Exterior Gateway Protocols and de-fact standard of Inter Domain routing protocol. BGP-4 is described in RFC1771, A Border Gateway Protocol 4 (BGP-4).

Many extensions have been added to RFC1771. RFC2858, Multiprotocol Extensions for BGP-4 provides multiprotocol support to BGP-4.


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10.1 Starting BGP

Default configuration file of bgpd is bgpd.conf. bgpd searches the current directory first then /etc/quagga/bgpd.conf. All of bgpd's command must be configured in bgpd.conf.

bgpd specific invocation options are described below. Common options may also be specified (see Common Invocation Options).

-p PORT
--bgp_port=PORT
Set the bgp protocol's port number.
-r
--retain
When program terminates, retain BGP routes added by zebra.


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10.2 BGP router

First of all you must configure BGP router with router bgp command. To configure BGP router, you need AS number. AS number is an identification of autonomous system. BGP protocol uses the AS number for detecting whether the BGP connection is internal one or external one.

— Command: router bgp asn

Enable a BGP protocol process with the specified asn. After this statement you can input any BGP Commands. You can not create different BGP process under different asn without specifying multiple-instance (see Multiple instance).

— Command: no router bgp asn

Destroy a BGP protocol process with the specified asn.

— BGP: bgp router-id A.B.C.D

This command specifies the router-ID. If bgpd connects to zebra it gets interface and address information. In that case default router ID value is selected as the largest IP Address of the interfaces. When router zebra is not enabled bgpd can't get interface information so router-id is set to 0.0.0.0. So please set router-id by hand.


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10.2.1 BGP distance

— BGP: distance bgp <1-255> <1-255> <1-255>

This command change distance value of BGP. Each argument is distance value for external routes, internal routes and local routes.

— BGP: distance <1-255> A.B.C.D/M
— BGP: distance <1-255> A.B.C.D/M word

This command set distance value to


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10.2.2 BGP decision process

1. Weight check
2. Local preference check.
3. Local route check.
4. AS path length check.
5. Origin check.
6. MED check.
— BGP: bgp bestpath as-path confed

This command specifies that the length of confederation path sets and sequences should should be taken into account during the BGP best path decision process.


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10.2.3 BGP route flap dampening

— BGP: bgp dampening <1-45> <1-20000> <1-20000> <1-255>

This command enables BGP route-flap dampening and specifies dampening parameters.

half-life
Half-life time for the penalty
reuse-threshold
Value to start reusing a route
suppress-threshold
Value to start suppressing a route
max-suppress
Maximum duration to suppress a stable route

The route-flap damping algorithm is compatible with RFC2439. The use of this command is not recommended nowadays, see RIPE-378.


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10.3 BGP network


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10.3.1 BGP route

— BGP: network A.B.C.D/M

This command adds the announcement network.

          router bgp 1
           network 10.0.0.0/8

This configuration example says that network 10.0.0.0/8 will be announced to all neighbors. Some vendors' routers don't advertise routes if they aren't present in their IGP routing tables; bgpd doesn't care about IGP routes when announcing its routes.

— BGP: no network A.B.C.D/M


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10.3.2 Route Aggregation

— BGP: aggregate-address A.B.C.D/M

This command specifies an aggregate address.

— BGP: aggregate-address A.B.C.D/M as-set

This command specifies an aggregate address. Resulting routes inlucde AS set.

— BGP: aggregate-address A.B.C.D/M summary-only

This command specifies an aggregate address. Aggreated routes will not be announce.

— BGP: no aggregate-address A.B.C.D/M


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10.3.3 Redistribute to BGP

— BGP: redistribute kernel

Redistribute kernel route to BGP process.

— BGP: redistribute static

Redistribute static route to BGP process.

— BGP: redistribute connected

Redistribute connected route to BGP process.

— BGP: redistribute rip

Redistribute RIP route to BGP process.

— BGP: redistribute ospf

Redistribute OSPF route to BGP process.


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10.4 BGP Peer


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10.4.1 Defining Peer

— BGP: neighbor peer remote-as asn

Creates a new neighbor whose remote-as is asn. peer can be an IPv4 address or an IPv6 address.

          router bgp 1
           neighbor 10.0.0.1 remote-as 2

In this case my router, in AS-1, is trying to peer with AS-2 at 10.0.0.1.

This command must be the first command used when configuring a neighbor. If the remote-as is not specified, bgpd will complain like this:

          can't find neighbor 10.0.0.1


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10.4.2 BGP Peer commands

In a router bgp clause there are neighbor specific configurations required.

— BGP: neighbor peer shutdown
— BGP: no neighbor peer shutdown

Shutdown the peer. We can delete the neighbor's configuration by no neighbor peer remote-as as-number but all configuration of the neighbor will be deleted. When you want to preserve the configuration, but want to drop the BGP peer, use this syntax.

— BGP: neighbor peer ebgp-multihop
— BGP: no neighbor peer ebgp-multihop
— BGP: neighbor peer description ...
— BGP: no neighbor peer description ...

Set description of the peer.

— BGP: neighbor peer version version

Set up the neighbor's BGP version. version can be 4, 4+ or 4-. BGP version 4 is the default value used for BGP peering. BGP version 4+ means that the neighbor supports Multiprotocol Extensions for BGP-4. BGP version 4- is similar but the neighbor speaks the old Internet-Draft revision 00's Multiprotocol Extensions for BGP-4. Some routing software is still using this version.

— BGP: neighbor peer interface ifname
— BGP: no neighbor peer interface ifname

When you connect to a BGP peer over an IPv6 link-local address, you have to specify the ifname of the interface used for the connection. To specify IPv4 session addresses, see the neighbor peer update-source command below.

This command is deprecated and may be removed in a future release. Its use should be avoided.

— BGP: neighbor peer next-hop-self
— BGP: no neighbor peer next-hop-self

This command specifies an announced route's nexthop as being equivalent to the address of the bgp router.

— BGP: neighbor peer update-source <ifname|address>
— BGP: no neighbor peer update-source

Specify the IPv4 source address to use for the BGP session to this neighbour, may be specified as either an IPv4 address directly or as an interface name (in which case the zebra daemon MUST be running in order for bgpd to be able to retrieve interface state).

          router bgp 64555
           neighbor foo update-source 192.168.0.1
           neighbor bar update-source lo0
— BGP: neighbor peer default-originate
— BGP: no neighbor peer default-originate

bgpd's default is to not announce the default route (0.0.0.0/0) even it is in routing table. When you want to announce default routes to the peer, use this command.

— BGP: neighbor peer port port
— BGP: neighbor peer port port
— BGP: neighbor peer send-community
— BGP: neighbor peer send-community
— BGP: neighbor peer weight weight
— BGP: no neighbor peer weight weight

This command specifies a default weight value for the neighbor's routes.

— BGP: neighbor peer maximum-prefix number
— BGP: no neighbor peer maximum-prefix number


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10.4.3 Peer filtering

— BGP: neighbor peer distribute-list name [in|out]

This command specifies a distribute-list for the peer. direct is ‘in’ or ‘out’.

— BGP command: neighbor peer prefix-list name [in|out]
— BGP command: neighbor peer filter-list name [in|out]
— BGP: neighbor peer route-map name [in|out]

Apply a route-map on the neighbor. direct must be in or out.


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10.5 BGP Peer Group

— BGP: neighbor word peer-group

This command defines a new peer group.

— BGP: neighbor peer peer-group word

This command bind specific peer to peer group word.


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10.6 BGP Address Family


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10.7 Autonomous System

The AS (Autonomous System) number is one of the essential element of BGP. BGP is a distance vector routing protocol, and the AS-Path framework provides distance vector metric and loop detection to BGP. RFC1930, Guidelines for creation, selection, and registration of an Autonomous System (AS) provides some background on the concepts of an AS.

The AS number is a two octet value, ranging in value from 1 to 65535. The AS numbers 64512 through 65535 are defined as private AS numbers. Private AS numbers must not to be advertised in the global Internet.


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10.7.1 AS Path Regular Expression

AS path regular expression can be used for displaying BGP routes and AS path access list. AS path regular expression is based on POSIX 1003.2 regular expressions. Following description is just a subset of POSIX regular expression. User can use full POSIX regular expression. Adding to that special character '_' is added for AS path regular expression.

.
Matches any single character.
*
Matches 0 or more occurrences of pattern.
+
Matches 1 or more occurrences of pattern.
?
Match 0 or 1 occurrences of pattern.
^
Matches the beginning of the line.
$
Matches the end of the line.
_
Character _ has special meanings in AS path regular expression. It matches to space and comma , and AS set delimiter { and } and AS confederation delimiter ( and ). And it also matches to the beginning of the line and the end of the line. So _ can be used for AS value boundaries match. show ip bgp regexp _7675_ matches to all of BGP routes which as AS number include 7675.


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10.7.2 Display BGP Routes by AS Path

To show BGP routes which has specific AS path information show ip bgp command can be used.

— Command: show ip bgp regexp line

This commands display BGP routes that matches AS path regular expression line.


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10.7.3 AS Path Access List

AS path access list is user defined AS path.

— Command: ip as-path access-list word {permit|deny} line

This command defines a new AS path access list.

— Command: no ip as-path access-list word
— Command: no ip as-path access-list word {permit|deny} line


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10.7.4 Using AS Path in Route Map

— Route Map: match as-path word
— Route Map: set as-path prepend as-path


Previous: Using AS Path in Route Map, Up: Autonomous System

10.7.5 Private AS Numbers


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10.8 BGP Communities Attribute

BGP communities attribute is widely used for implementing policy routing. Network operators can manipulate BGP communities attribute based on their network policy. BGP communities attribute is defined in RFC1997, BGP Communities Attribute and RFC1998, An Application of the BGP Community Attribute in Multi-home Routing. It is an optional transitive attribute, therefore local policy can travel through different autonomous system.

Communities attribute is a set of communities values. Each communities value is 4 octet long. The following format is used to define communities value.

AS:VAL
This format represents 4 octet communities value. AS is high order 2 octet in digit format. VAL is low order 2 octet in digit format. This format is useful to define AS oriented policy value. For example, 7675:80 can be used when AS 7675 wants to pass local policy value 80 to neighboring peer.
internet
internet represents well-known communities value 0.
no-export
no-export represents well-known communities value NO_EXPORT
(0xFFFFFF01). All routes carry this value must not be advertised to outside a BGP confederation boundary. If neighboring BGP peer is part of BGP confederation, the peer is considered as inside a BGP confederation boundary, so the route will be announced to the peer.
no-advertise
no-advertise represents well-known communities value NO_ADVERTISE
(0xFFFFFF02). All routes carry this value must not be advertise to other BGP peers.
local-AS
local-AS represents well-known communities value NO_EXPORT_SUBCONFED (0xFFFFFF03). All routes carry this value must not be advertised to external BGP peers. Even if the neighboring router is part of confederation, it is considered as external BGP peer, so the route will not be announced to the peer.

When BGP communities attribute is received, duplicated communities value in the communities attribute is ignored and each communities values are sorted in numerical order.


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10.8.1 BGP Community Lists

BGP community list is a user defined BGP communites attribute list. BGP community list can be used for matching or manipulating BGP communities attribute in updates.

There are two types of community list. One is standard community list and another is expanded community list. Standard community list defines communities attribute. Expanded community list defines communities attribute string with regular expression. Standard community list is compiled into binary format when user define it. Standard community list will be directly compared to BGP communities attribute in BGP updates. Therefore the comparison is faster than expanded community list.

— Command: ip community-list standard name {permit|deny} community

This command defines a new standard community list. community is communities value. The community is compiled into community structure. We can define multiple community list under same name. In that case match will happen user defined order. Once the community list matches to communities attribute in BGP updates it return permit or deny by the community list definition. When there is no matched entry, deny will be returned. When community is empty it matches to any routes.

— Command: ip community-list expanded name {permit|deny} line

This command defines a new expanded community list. line is a string expression of communities attribute. line can include regular expression to match communities attribute in BGP updates.

— Command: no ip community-list name
— Command: no ip community-list standard name
— Command: no ip community-list expanded name

These commands delete community lists specified by name. All of community lists shares a single name space. So community lists can be removed simpley specifying community lists name.

— Command: show ip community-list
— Command: show ip community-list name

This command display current community list information. When name is specified the specified community list's information is shown.

          # show ip community-list
          Named Community standard list CLIST
              permit 7675:80 7675:100 no-export
              deny internet
          Named Community expanded list EXPAND
              permit :
          
          # show ip community-list CLIST
          Named Community standard list CLIST
              permit 7675:80 7675:100 no-export
              deny internet


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10.8.2 Numbered BGP Community Lists

When number is used for BGP community list name, the number has special meanings. Community list number in the range from 1 and 99 is standard community list. Community list number in the range from 100 to 199 is expanded community list. These community lists are called as numbered community lists. On the other hand normal community lists is called as named community lists.

— Command: ip community-list <1-99> {permit|deny} community

This command defines a new community list. <1-99> is standard community list number. Community list name within this range defines standard community list. When community is empty it matches to any routes.

— Command: ip community-list <100-199> {permit|deny} community

This command defines a new community list. <100-199> is expanded community list number. Community list name within this range defines expanded community list.

— Command: ip community-list name {permit|deny} community

When community list type is not specifed, the community list type is automatically detected. If community can be compiled into communities attribute, the community list is defined as a standard community list. Otherwise it is defined as an expanded community list. This feature is left for backward compability. Use of this feature is not recommended.


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10.8.3 BGP Community in Route Map

In Route Map (see Route Map), we can match or set BGP communities attribute. Using this feature network operator can implement their network policy based on BGP communities attribute.

Following commands can be used in Route Map.

— Route Map: match community word
— Route Map: match community word exact-match

This command perform match to BGP updates using community list word. When the one of BGP communities value match to the one of communities value in community list, it is match. When exact-match keyword is spcified, match happen only when BGP updates have completely same communities value specified in the community list.

— Route Map: set community none
— Route Map: set community community
— Route Map: set community community additive

This command manipulate communities value in BGP updates. When none is specified as communities value, it removes entire communities attribute from BGP updates. When community is not none, specified communities value is set to BGP updates. If BGP updates already has BGP communities value, the existing BGP communities value is replaced with specified community value. When additive keyword is specified, community is appended to the existing communities value.

— Route Map: set comm-list word delete

This command remove communities value from BGP communities attribute. The word is community list name. When BGP route's communities value matches to the community list word, the communities value is removed. When all of communities value is removed eventually, the BGP update's communities attribute is completely removed.


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10.8.4 Display BGP Routes by Community

To show BGP routes which has specific BGP communities attribute, show ip bgp command can be used. The community value and community list can be used for show ip bgp command.

— Command: show ip bgp community
— Command: show ip bgp community community
— Command: show ip bgp community community exact-match

show ip bgp community displays BGP routes which has communities attribute. When community is specified, BGP routes that matches community value is displayed. For this command, internet keyword can't be used for community value. When exact-match is specified, it display only routes that have an exact match.

— Command: show ip bgp community-list word
— Command: show ip bgp community-list word exact-match

This commands display BGP routes that matches community list word. When exact-match is specified, display only routes that have an exact match.


Previous: Display BGP Routes by Community, Up: BGP Communities Attribute

10.8.5 Using BGP Communities Attribute

Following configuration is the most typical usage of BGP communities attribute. AS 7675 provides upstream Internet connection to AS 100. When following configuration exists in AS 7675, AS 100 networks operator can set local preference in AS 7675 network by setting BGP communities attribute to the updates.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list 70 permit 7675:70
     ip community-list 70 deny
     ip community-list 80 permit 7675:80
     ip community-list 80 deny
     ip community-list 90 permit 7675:90
     ip community-list 90 deny
     !
     route-map RMAP permit 10
      match community 70
      set local-preference 70
     !
     route-map RMAP permit 20
      match community 80
      set local-preference 80
     !
     route-map RMAP permit 30
      match community 90
      set local-preference 90

Following configuration announce 10.0.0.0/8 from AS 100 to AS 7675. The route has communities value 7675:80 so when above configuration exists in AS 7675, announced route's local preference will be set to value 80.

     router bgp 100
      network 10.0.0.0/8
      neighbor 192.168.0.2 remote-as 7675
      neighbor 192.168.0.2 route-map RMAP out
     !
     ip prefix-list PLIST permit 10.0.0.0/8
     !
     route-map RMAP permit 10
      match ip address prefix-list PLIST
      set community 7675:80

Following configuration is an example of BGP route filtering using communities attribute. This configuration only permit BGP routes which has BGP communities value 0:80 or 0:90. Network operator can put special internal communities value at BGP border router, then limit the BGP routes announcement into the internal network.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list 1 permit 0:80 0:90
     !
     route-map RMAP permit in
      match community 1

Following exmaple filter BGP routes which has communities value 1:1. When there is no match community-list returns deny. To avoid filtering all of routes, we need to define permit any at last.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list standard FILTER deny 1:1
     ip community-list standard FILTER permit
     !
     route-map RMAP permit 10
      match community FILTER

Communities value keyword internet has special meanings in standard community lists. In below example internet act as match any. It matches all of BGP routes even if the route does not have communities attribute at all. So community list INTERNET is same as above example's FILTER.

     ip community-list standard INTERNET deny 1:1
     ip community-list standard INTERNET permit internet

Following configuration is an example of communities value deletion. With this configuration communities value 100:1 and 100:2 is removed from BGP updates. For communities value deletion, only permit community-list is used. deny community-list is ignored.

     router bgp 7675
      neighbor 192.168.0.1 remote-as 100
      neighbor 192.168.0.1 route-map RMAP in
     !
     ip community-list standard DEL permit 100:1 100:2
     !
     route-map RMAP permit 10
      set comm-list DEL delete


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10.9 BGP Extended Communities Attribute

BGP extended communities attribute is introduced with MPLS VPN/BGP technology. MPLS VPN/BGP expands capability of network infrastructure to provide VPN functionality. At the same time it requires a new framework for policy routing. With BGP Extended Communities Attribute we can use Route Target or Site of Origin for implementing network policy for MPLS VPN/BGP.

BGP Extended Communities Attribute is similar to BGP Communities Attribute. It is an optional transitive attribute. BGP Extended Communities Attribute can carry multiple Extended Community value. Each Extended Community value is eight octet length.

BGP Extended Communities Attribute provides an extended range compared with BGP Communities Attribute. Adding to that there is a type field in each value to provides community space structure.

There are two format to define Extended Community value. One is AS based format the other is IP address based format.

AS:VAL
This is a format to define AS based Extended Community value. AS part is 2 octets Global Administrator subfield in Extended Community value. VAL part is 4 octets Local Administrator subfield. 7675:100 represents AS 7675 policy value 100.
IP-Address:VAL
This is a format to define IP address based Extended Community value. IP-Address part is 4 octets Global Administrator subfield. VAL part is 2 octets Local Administrator subfield. 10.0.0.1:100 represents


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10.9.1 BGP Extended Community Lists

Expanded Community Lists is a user defined BGP Expanded Community Lists.

— Command: ip extcommunity-list standard name {permit|deny} extcommunity

This command defines a new standard extcommunity-list. extcommunity is extended communities value. The extcommunity is compiled into extended community structure. We can define multiple extcommunity-list under same name. In that case match will happen user defined order. Once the extcommunity-list matches to extended communities attribute in BGP updates it return permit or deny based upon the extcommunity-list definition. When there is no matched entry, deny will be returned. When extcommunity is empty it matches to any routes.

— Command: ip extcommunity-list expanded name {permit|deny} line

This command defines a new expanded extcommunity-list. line is a string expression of extended communities attribute. line can include regular expression to match extended communities attribute in BGP updates.

— Command: no ip extcommunity-list name
— Command: no ip extcommunity-list standard name
— Command: no ip extcommunity-list expanded name

These commands delete extended community lists specified by name. All of extended community lists shares a single name space. So extended community lists can be removed simpley specifying the name.

— Command: show ip extcommunity-list
— Command: show ip extcommunity-list name

This command display current extcommunity-list information. When name is specified the community list's information is shown.

          # show ip extcommunity-list


Previous: BGP Extended Community Lists, Up: BGP Extended Communities Attribute

10.9.2 BGP Extended Communities in Route Map

— Route Map: match extcommunity word
— Route Map: set extcommunity rt extcommunity

This command set Route Target value.

— Route Map: set extcommunity soo extcommunity

This command set Site of Origin value.


Next: , Previous: BGP Extended Communities Attribute, Up: BGP

10.10 Displaying BGP Routes


Next: , Up: Displaying BGP routes

10.10.1 Show IP BGP

— Command: show ip bgp
— Command: show ip bgp A.B.C.D
— Command: show ip bgp X:X::X:X

This command displays BGP routes. When no route is specified it display all of IPv4 BGP routes.

     BGP table version is 0, local router ID is 10.1.1.1
     Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
     Origin codes: i - IGP, e - EGP, ? - incomplete
     
        Network          Next Hop            Metric LocPrf Weight Path
     *> 1.1.1.1/32       0.0.0.0                  0         32768 i
     
     Total number of prefixes 1


Previous: Show IP BGP, Up: Displaying BGP routes

10.10.2 More Show IP BGP

— Command: show ip bgp regexp line

This command display BGP routes using AS path regular expression (see Display BGP Routes by AS Path).

— Command: show ip bgp community community
— Command: show ip bgp community community exact-match

This command display BGP routes using community (see Display BGP Routes by Community).

— Command: show ip bgp community-list word
— Command: show ip bgp community-list word exact-match

This command display BGP routes using community list (see Display BGP Routes by Community).

— Command: show ip bgp summary
— Command: show ip bgp neighbor [peer]
— Command: clear ip bgp peer

Clear peers which have addresses of X.X.X.X

— Command: clear ip bgp peer soft in

Clear peer using soft reconfiguration.

— Command: show ip bgp dampened-paths

Display paths suppressed due to dampening

— Command: show ip bgp flap-statistics

Display flap statistics of routes

— Command: show debug
— Command: debug event
— Command: debug update
— Command: debug keepalive
— Command: no debug event
— Command: no debug update
— Command: no debug keepalive


Next: , Previous: Displaying BGP routes, Up: BGP

10.11 Capability Negotiation

When adding IPv6 routing information exchange feature to BGP. There were some proposals. IETF (Internet Engineering Task Force) IDR (Inter Domain Routing) WG (Working group) adopted a proposal called Multiprotocol Extension for BGP. The specification is described in RFC2283. The protocol does not define new protocols. It defines new attributes to existing BGP. When it is used exchanging IPv6 routing information it is called BGP-4+. When it is used for exchanging multicast routing information it is called MBGP.

bgpd supports Multiprotocol Extension for BGP. So if remote peer supports the protocol, bgpd can exchange IPv6 and/or multicast routing information.

Traditional BGP did not have the feature to detect remote peer's capabilities, e.g. whether it can handle prefix types other than IPv4 unicast routes. This was a big problem using Multiprotocol Extension for BGP to operational network. RFC2842, Capabilities Advertisement with BGP-4 adopted a feature called Capability Negotiation. bgpd use this Capability Negotiation to detect the remote peer's capabilities. If the peer is only configured as IPv4 unicast neighbor, bgpd does not send these Capability Negotiation packets (at least not unless other optional BGP features require capability negotation).

By default, Quagga will bring up peering with minimal common capability for the both sides. For example, local router has unicast and multicast capabilitie and remote router has unicast capability. In this case, the local router will establish the connection with unicast only capability. When there are no common capabilities, Quagga sends Unsupported Capability error and then resets the connection.

If you want to completely match capabilities with remote peer. Please use strict-capability-match command.

— BGP: neighbor peer strict-capability-match
— BGP: no neighbor peer strict-capability-match

Strictly compares remote capabilities and local capabilities. If capabilities are different, send Unsupported Capability error then reset connection.

You may want to disable sending Capability Negotiation OPEN message optional parameter to the peer when remote peer does not implement Capability Negotiation. Please use dont-capability-negotiate command to disable the feature.

— BGP: neighbor peer dont-capability-negotiate
— BGP: no neighbor peer dont-capability-negotiate

Suppress sending Capability Negotiation as OPEN message optional parameter to the peer. This command only affects the peer is configured other than IPv4 unicast configuration.

When remote peer does not have capability negotiation feature, remote peer will not send any capabilities at all. In that case, bgp configures the peer with configured capabilities.

You may prefer locally configured capabilities more than the negotiated capabilities even though remote peer sends capabilities. If the peer is configured by override-capability, bgpd ignores received capabilities then override negotiated capabilities with configured values.

— BGP: neighbor peer override-capability
— BGP: no neighbor peer override-capability

Override the result of Capability Negotiation with local configuration. Ignore remote peer's capability value.


Next: , Previous: Capability Negotiation, Up: BGP

10.12 Route Reflector

— BGP: bgp cluster-id a.b.c.d
— BGP: neighbor peer route-reflector-client
— BGP: no neighbor peer route-reflector-client


Next: , Previous: Route Reflector, Up: BGP

10.13 Route Server

At an Internet Exchange point, many ISPs are connected to each other by external BGP peering. Normally these external BGP connection are done by ‘full mesh’ method. As with internal BGP full mesh formation, this method has a scaling problem.

This scaling problem is well known. Route Server is a method to resolve the problem. Each ISP's BGP router only peers to Route Server. Route Server serves as BGP information exchange to other BGP routers. By applying this method, numbers of BGP connections is reduced from O(n*(n-1)/2) to O(n).

Unlike normal BGP router, Route Server must have several routing tables for managing different routing policies for each BGP speaker. We call the routing tables as different views. bgpd can work as normal BGP router or Route Server or both at the same time.


Next: , Up: Route Server

10.13.1 Multiple instance

To enable multiple view function of bgpd, you must turn on multiple instance feature beforehand.

— Command: bgp multiple-instance

Enable BGP multiple instance feature. After this feature is enabled, you can make multiple BGP instances or multiple BGP views.

— Command: no bgp multiple-instance

Disable BGP multiple instance feature. You can not disable this feature when BGP multiple instances or views exist.

When you want to make configuration more Cisco like one,

— Command: bgp config-type cisco

Cisco compatible BGP configuration output.

When bgp config-type cisco is specified,

“no synchronization” is displayed. “no auto-summary” is displayed.

“network” and “aggregate-address” argument is displayed as “A.B.C.D M.M.M.M”

Quagga: network 10.0.0.0/8 Cisco: network 10.0.0.0

Quagga: aggregate-address 192.168.0.0/24 Cisco: aggregate-address 192.168.0.0 255.255.255.0

Community attribute handling is also different. If there is no configuration is specified community attribute and extended community attribute are sent to neighbor. When user manually disable the feature community attribute is not sent to the neighbor. In case of bgp config-type cisco is specified, community attribute is not sent to the neighbor by default. To send community attribute user has to specify neighbor A.B.C.D send-community command.

     !
     router bgp 1
      neighbor 10.0.0.1 remote-as 1
      no neighbor 10.0.0.1 send-community
     !
     router bgp 1
      neighbor 10.0.0.1 remote-as 1
      neighbor 10.0.0.1 send-community
     !
— Command: bgp config-type zebra

Quagga style BGP configuration. This is default.


Next: , Previous: Multiple instance, Up: Route Server

10.13.2 BGP instance and view

BGP instance is a normal BGP process. The result of route selection goes to the kernel routing table. You can setup different AS at the same time when BGP multiple instance feature is enabled.

— Command: router bgp as-number

Make a new BGP instance. You can use arbitrary word for the name.

     bgp multiple-instance
     !
     router bgp 1
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.2 remote-as 3
     !
     router bgp 2
      neighbor 10.0.0.3 remote-as 4
      neighbor 10.0.0.4 remote-as 5

BGP view is almost same as normal BGP process. The result of route selection does not go to the kernel routing table. BGP view is only for exchanging BGP routing information.

— Command: router bgp as-number view name

Make a new BGP view. You can use arbitrary word for the name. This view's route selection result does not go to the kernel routing table.

With this command, you can setup Route Server like below.

     bgp multiple-instance
     !
     router bgp 1 view 1
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.2 remote-as 3
     !
     router bgp 2 view 2
      neighbor 10.0.0.3 remote-as 4
      neighbor 10.0.0.4 remote-as 5


Next: , Previous: BGP instance and view, Up: Route Server

10.13.3 Routing policy

You can set different routing policy for a peer. For example, you can set different filter for a peer.

     bgp multiple-instance
     !
     router bgp 1 view 1
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.1 distribute-list 1 in
     !
     router bgp 1 view 2
      neighbor 10.0.0.1 remote-as 2
      neighbor 10.0.0.1 distribute-list 2 in

This means BGP update from a peer 10.0.0.1 goes to both BGP view 1 and view 2. When the update is inserted into view 1, distribute-list 1 is applied. On the other hand, when the update is inserted into view 2, distribute-list 2 is applied.


Previous: Routing policy, Up: Route Server

10.13.4 Viewing the view

To display routing table of BGP view, you must specify view name.

— Command: show ip bgp view name

Display routing table of BGP view name.


Next: , Previous: Route Server, Up: BGP

10.14 How to set up a 6-Bone connection

     zebra configuration
     ===================
     !
     ! Actually there is no need to configure zebra
     !
     
     bgpd configuration
     ==================
     !
     ! This means that routes go through zebra and into the kernel.
     !
     router zebra
     !
     ! MP-BGP configuration
     !
     router bgp 7675
      bgp router-id 10.0.0.1
      neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 remote-as as-number
     !
      address-family ipv6
      network 3ffe:506::/32
      neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 activate
      neighbor 3ffe:1cfa:0:2:2a0:c9ff:fe9e:f56 route-map set-nexthop out
      neighbor 3ffe:1cfa:0:2:2c0:4fff:fe68:a231 remote-as as-number
      neighbor 3ffe:1cfa:0:2:2c0:4fff:fe68:a231 route-map set-nexthop out
      exit-address-family
     !
     ipv6 access-list all permit any
     !
     ! Set output nexthop address.
     !
     route-map set-nexthop permit 10
      match ipv6 address all
      set ipv6 nexthop global 3ffe:1cfa:0:2:2c0:4fff:fe68:a225
      set ipv6 nexthop local fe80::2c0:4fff:fe68:a225
     !
     ! logfile FILENAME is obsolete.  Please use log file FILENAME
     
     log file bgpd.log
     !


Next: , Previous: How to set up a 6-Bone connection, Up: BGP

10.15 Dump BGP packets and table

— Command: dump bgp all path
— Command: dump bgp all path interval

Dump all BGP packet and events to path file.

— Command: dump bgp updates path
— Command: dump bgp updates path interval

Dump BGP updates to path file.

— Command: dump bgp routes path
— Command: dump bgp routes path

Dump whole BGP routing table to path. This is heavy process.


Previous: Dump BGP packets and table, Up: BGP

10.16 BGP Configuration Examples

Example of a session to an upstream, advertising only one prefix to it.

     router bgp 64512
      bgp router-id 10.236.87.1
      network 10.236.87.0/24
      neighbor upstream peer-group
      neighbor upstream remote-as 64515
      neighbor upstream capability dynamic
      neighbor upstream prefix-list pl-allowed-adv out
      neighbor 10.1.1.1 peer-group upstream
      neighbor 10.1.1.1 description ACME ISP
     !
     ip prefix-list pl-allowed-adv seq 5 permit 82.195.133.0/25
     ip prefix-list pl-allowed-adv seq 10 deny any
     

A more complex example. With upstream, peer and customer sessions. Advertising global prefixes and NO_EXPORT prefixes and providing actions for customer routes based on community values. Extensive use of route-maps and the 'call' feature to support selective advertising of prefixes. This example is intended as guidance only, it has NOT been tested and almost certainly containts silly mistakes, if not serious flaws.

     router bgp 64512
      bgp router-id 10.236.87.1
      network 10.123.456.0/24
      network 10.123.456.128/25 route-map rm-no-export
      neighbor upstream capability dynamic
      neighbor upstream route-map rm-upstream-out out
      neighbor cust capability dynamic
      neighbor cust route-map rm-cust-in in
      neighbor cust route-map rm-cust-out out
      neighbor cust send-community both
      neighbor peer capability dynamic
      neighbor peer route-map rm-peer-in in
      neighbor peer route-map rm-peer-out out
      neighbor peer send-community both
      neighbor 10.1.1.1 remote-as 64515
      neighbor 10.1.1.1 peer-group upstream
      neighbor 10.2.1.1 remote-as 64516
      neighbor 10.2.1.1 peer-group upstream
      neighbor 10.3.1.1 remote-as 64517
      neighbor 10.3.1.1 peer-group cust-default
      neighbor 10.3.1.1 description customer1
      neighbor 10.3.1.1 prefix-list pl-cust1-network in
      neighbor 10.4.1.1 remote-as 64518
      neighbor 10.4.1.1 peer-group cust
      neighbor 10.4.1.1 prefix-list pl-cust2-network in
      neighbor 10.4.1.1 description customer2
      neighbor 10.5.1.1 remote-as 64519
      neighbor 10.5.1.1 peer-group peer
      neighbor 10.5.1.1 prefix-list pl-peer1-network in
      neighbor 10.5.1.1 description peer AS 1
      neighbor 10.6.1.1 remote-as 64520
      neighbor 10.6.1.1 peer-group peer
      neighbor 10.6.1.1 prefix-list pl-peer2-network in
      neighbor 10.6.1.1 description peer AS 2
     !
     ip prefix-list pl-default permit 0.0.0.0/0
     !
     ip prefix-list pl-upstream-peers permit 10.1.1.1/32
     ip prefix-list pl-upstream-peers permit 10.2.1.1/32
     !
     ip prefix-list pl-cust1-network permit 10.3.1.0/24
     ip prefix-list pl-cust1-network permit 10.3.2.0/24
     !
     ip prefix-list pl-cust2-network permit 10.4.1.0/24
     !
     ip prefix-list pl-peer1-network permit 10.5.1.0/24
     ip prefix-list pl-peer1-network permit 10.5.2.0/24
     ip prefix-list pl-peer1-network permit 192.168.0.0/24
     !
     ip prefix-list pl-peer2-network permit 10.6.1.0/24
     ip prefix-list pl-peer2-network permit 10.6.2.0/24
     ip prefix-list pl-peer2-network permit 192.168.1.0/24
     ip prefix-list pl-peer2-network permit 192.168.2.0/24
     ip prefix-list pl-peer2-network permit 172.16.1/24
     !
     ip as-path access-list asp-own-as permit ^$
     ip as-path access-list asp-own-as permit _64512_
     !
     ! #################################################################
     ! Match communities we provide actions for, on routes receives from
     ! customers. Communities values of <our-ASN>:X, with X, have actions:
     !
     ! 100 - blackhole the prefix
     ! 200 - set no_export
     ! 300 - advertise only to other customers
     ! 400 - advertise only to upstreams
     ! 500 - set no_export when advertising to upstreams
     ! 2X00 - set local_preference to X00
     !
     ! blackhole the prefix of the route
     ip community-list standard cm-blackhole permit 64512:100
     !
     ! set no-export community before advertising
     ip community-list standard cm-set-no-export permit 64512:200
     !
     ! advertise only to other customers
     ip community-list standard cm-cust-only permit 64512:300
     !
     ! advertise only to upstreams
     ip community-list standard cm-upstream-only permit 64512:400
     !
     ! advertise to upstreams with no-export
     ip community-list standard cm-upstream-noexport permit 64512:500
     !
     ! set local-pref to least significant 3 digits of the community
     ip community-list standard cm-prefmod-100 permit 64512:2100
     ip community-list standard cm-prefmod-200 permit 64512:2200
     ip community-list standard cm-prefmod-300 permit 64512:2300
     ip community-list standard cm-prefmod-400 permit 64512:2400
     ip community-list expanded cme-prefmod-range permit 64512:2...
     !
     ! Informational communities
     !
     ! 3000 - learned from upstream
     ! 3100 - learned from customer
     ! 3200 - learned from peer
     !
     ip community-list standard cm-learnt-upstream permit 64512:3000
     ip community-list standard cm-learnt-cust permit 64512:3100
     ip community-list standard cm-learnt-peer permit 64512:3200
     !
     ! ###################################################################
     ! Utility route-maps
     !
     ! These utility route-maps generally should not used to permit/deny
     ! routes, i.e. they do not have meaning as filters, and hence probably
     ! should be used with 'on-match next'. These all finish with an empty
     ! permit entry so as not interfere with processing in the caller.
     !
     route-map rm-no-export permit 10
      set community additive no-export
     route-map rm-no-export permit 20
     !
     route-map rm-blackhole permit 10
      description blackhole, up-pref and ensure it cant escape this AS
      set ip next-hop 127.0.0.1
      set local-preference 10
      set community additive no-export
     route-map rm-blackhole permit 20
     !
     ! Set local-pref as requested
     route-map rm-prefmod permit 10
      match community cm-prefmod-100
      set local-preference 100
     route-map rm-prefmod permit 20
      match community cm-prefmod-200
      set local-preference 200
     route-map rm-prefmod permit 30
      match community cm-prefmod-300
      set local-preference 300
     route-map rm-prefmod permit 40
      match community cm-prefmod-400
      set local-preference 400
     route-map rm-prefmod permit 50
     !
     ! Community actions to take on receipt of route.
     route-map rm-community-in permit 10
      description check for blackholing, no point continuing if it matches.
      match community cm-blackhole
      call rm-blackhole
     route-map rm-community-in permit 20
      match community cm-set-no-export
      call rm-no-export
      on-match next
     route-map rm-community-in permit 30
      match community cme-prefmod-range
      call rm-prefmod
     route-map rm-community-in permit 40
     !
     ! #####################################################################
     ! Community actions to take when advertising a route.
     ! These are filtering route-maps,
     !
     ! Deny customer routes to upstream with cust-only set.
     route-map rm-community-filt-to-upstream deny 10
      match community cm-learnt-cust
      match community cm-cust-only
     route-map rm-community-filt-to-upstream permit 20
     !
     ! Deny customer routes to other customers with upstream-only set.
     route-map rm-community-filt-to-cust deny 10
      match community cm-learnt-cust
      match community cm-upstream-only
     route-map rm-community-filt-to-cust permit 20
     !
     ! ###################################################################
     ! The top-level route-maps applied to sessions. Further entries could
     ! be added obviously..
     !
     ! Customers
     route-map rm-cust-in permit 10
      call rm-community-in
      on-match next
     route-map rm-cust-in permit 20
      set community additive 64512:3100
     route-map rm-cust-in permit 30
     !
     route-map rm-cust-out permit 10
      call rm-community-filt-to-cust
      on-match next
     route-map rm-cust-out permit 20
     !
     ! Upstream transit ASes
     route-map rm-upstream-out permit 10
      description filter customer prefixes which are marked cust-only
      call rm-community-filt-to-upstream
      on-match next
     route-map rm-upstream-out permit 20
      description only customer routes are provided to upstreams/peers
      match community cm-learnt-cust
     !
     ! Peer ASes
     ! outbound policy is same as for upstream
     route-map rm-peer-out permit 10
      call rm-upstream-out
     !
     route-map rm-peer-in permit 10
      set community additive 64512:3200


Next: , Previous: BGP, Up: Top

11 Configuring Quagga as a Route Server

The purpose of a Route Server is to centralize the peerings between BGP speakers. For example if we have an exchange point scenario with four BGP speakers, each of which maintaining a BGP peering with the other three (see fig:full-mesh), we can convert it into a centralized scenario where each of the four establishes a single BGP peering against the Route Server (see fig:route-server).

We will first describe briefly the Route Server model implemented by Quagga. We will explain the commands that have been added for configuring that model. And finally we will show a full example of Quagga configured as Route Server.


Next: , Up: Configuring Quagga as a Route Server

11.1 Description of the Route Server model

First we are going to describe the normal processing that BGP announcements suffer inside a standard BGP speaker, as shown in fig:normal-processing, it consists of three steps:

Normal announcement processing

Figure 11.1: Announcement processing inside a “normal” BGP speaker

Full Mesh BGP Topology

Figure 11.2: Full Mesh

Route Server BGP Topology

Figure 11.3: Route Server and clients

Of course we want that the routing tables obtained in each of the routers are the same when using the route server than when not. But as a consequence of having a single BGP peering (against the route server), the BGP speakers can no longer distinguish from/to which peer each announce comes/goes. This means that the routers connected to the route server are not able to apply by themselves the same input/output filters as in the full mesh scenario, so they have to delegate those functions to the route server.

Even more, the “best path” selection must be also performed inside the route server on behalf of its clients. The reason is that if, after applying the filters of the announcer and the (potential) receiver, the route server decides to send to some client two or more different announcements referred to the same destination, the client will only retain the last one, considering it as an implicit withdrawal of the previous announcements for the same destination. This is the expected behavior of a BGP speaker as defined in RFC1771, and even though there are some proposals of mechanisms that permit multiple paths for the same destination to be sent through a single BGP peering, none are currently supported by most existing BGP implementations.

As a consequence a route server must maintain additional information and perform additional tasks for a RS-client that those necessary for common BGP peerings. Essentially a route server must:

When we talk about the “appropriate” filter, both the announcer and the receiver of the route must be taken into account. Suppose that the route server receives an announcement from client A, and the route server is considering it for the Loc-RIB of client B. The filters that should be applied are the same that would be used in the full mesh scenario, i.e., first the `Out' filter of router A for announcements going to router B, and then the `In' filter of router B for announcements coming from router A.

We call “Export Policy” of a RS-client to the set of `Out' filters that the client would use if there was no route server. The same applies for the “Import Policy” of a RS-client and the set of `In' filters of the client if there was no route server.

It is also common to demand from a route server that it does not modify some BGP attributes (next-hop, as-path and MED) that are usually modified by standard BGP speakers before announcing a route.

The announcement processing model implemented by Quagga is shown in fig:rs-processing. The figure shows a mixture of RS-clients (B, C and D) with normal BGP peers (A). There are some details that worth additional comments:

Route Server Processing Model

Figure 11.4: Announcement processing model implemented by the Route Server


Next: , Previous: Description of the Route Server model, Up: Configuring Quagga as a Route Server

11.2 Commands for configuring a Route Server

Now we will describe the commands that have been added to quagga in order to support the route server features.

— Route-Server: neighbor peer-group route-server-client
— Route-Server: neighbor A.B.C.D route-server-client
— Route-Server: neighbor X:X::X:X route-server-client

This command configures the peer given by peer, A.B.C.D or X:X::X:X as an RS-client.

Actually this command is not new, it already existed in standard Quagga. It enables the transparent mode for the specified peer. This means that some BGP attributes (as-path, next-hop and MED) of the routes announced to that peer are not modified.

With the route server patch, this command, apart from setting the transparent mode, creates a new Loc-RIB dedicated to the specified peer (those named `Loc-RIB for X' in Figure 11.4.). Starting from that moment, every announcement received by the route server will be also considered for the new Loc-RIB.

— Route-Server: neigbor {A.B.C.D|X.X::X.X|peer-group} route-map WORD {import|export}

This set of commands can be used to specify the route-map that represents the Import or Export policy of a peer which is configured as a RS-client (with the previous command).

— Route-Server: match peer {A.B.C.D|X:X::X:X}

This is a new match statement for use in route-maps, enabling them to describe import/export policies. As we said before, an import/export policy represents a set of input/output filters of the RS-client. This statement makes possible that a single route-map represents the full set of filters that a BGP speaker would use for its different peers in a non-RS scenario.

The match peer statement has different semantics whether it is used inside an import or an export route-map. In the first case the statement matches if the address of the peer who sends the announce is the same that the address specified by {A.B.C.D|X:X::X:X}. For export route-maps it matches when {A.B.C.D|X:X::X:X} is the address of the RS-Client into whose Loc-RIB the announce is going to be inserted (how the same export policy is applied before different Loc-RIBs is shown in Figure 11.4.).

— Route-map Command: call WORD

This command (also used inside a route-map) jumps into a different route-map, whose name is specified by WORD. When the called route-map finishes, depending on its result the original route-map continues or not. Apart from being useful for making import/export route-maps easier to write, this command can also be used inside any normal (in or out) route-map.


Previous: Commands for configuring a Route Server, Up: Configuring Quagga as a Route Server

11.3 Example of Route Server Configuration

Finally we are going to show how to configure a Quagga daemon to act as a Route Server. For this purpose we are going to present a scenario without route server, and then we will show how to use the configurations of the BGP routers to generate the configuration of the route server.

All the configuration files shown in this section have been taken from scenarios which were tested using the VNUML tool VNUML.


Next: , Up: Example of Route Server Configuration

11.3.1 Configuration of the BGP routers without Route Server

We will suppose that our initial scenario is an exchange point with three BGP capable routers, named RA, RB and RC. Each of the BGP speakers generates some routes (with the network command), and establishes BGP peerings against the other two routers. These peerings have In and Out route-maps configured, named like “PEER-X-IN” or “PEER-X-OUT”. For example the configuration file for router RA could be the following:

#Configuration for router 'RA'
!
hostname RA
password ****
!
router bgp 65001
  no bgp default ipv4-unicast
  neighbor 2001:0DB8::B remote-as 65002
  neighbor 2001:0DB8::C remote-as 65003
!
  address-family ipv6
    network 2001:0DB8:AAAA:1::/64
    network 2001:0DB8:AAAA:2::/64
    network 2001:0DB8:0000:1::/64
    network 2001:0DB8:0000:2::/64

    neighbor 2001:0DB8::B activate
    neighbor 2001:0DB8::B soft-reconfiguration inbound
    neighbor 2001:0DB8::B route-map PEER-B-IN in
    neighbor 2001:0DB8::B route-map PEER-B-OUT out

    neighbor 2001:0DB8::C activate
    neighbor 2001:0DB8::C soft-reconfiguration inbound
    neighbor 2001:0DB8::C route-map PEER-C-IN in
    neighbor 2001:0DB8::C route-map PEER-C-OUT out
  exit-address-family
!
ipv6 prefix-list COMMON-PREFIXES seq  5 permit 2001:0DB8:0000::/48 ge 64 le 64
ipv6 prefix-list COMMON-PREFIXES seq 10 deny any
!
ipv6 prefix-list PEER-A-PREFIXES seq  5 permit 2001:0DB8:AAAA::/48 ge 64 le 64
ipv6 prefix-list PEER-A-PREFIXES seq 10 deny any
!
ipv6 prefix-list PEER-B-PREFIXES seq  5 permit 2001:0DB8:BBBB::/48 ge 64 le 64
ipv6 prefix-list PEER-B-PREFIXES seq 10 deny any
!
ipv6 prefix-list PEER-C-PREFIXES seq  5 permit 2001:0DB8:CCCC::/48 ge 64 le 64
ipv6 prefix-list PEER-C-PREFIXES seq 10 deny any
!
route-map PEER-B-IN permit 10
  match ipv6 address prefix-list COMMON-PREFIXES
  set metric 100
route-map PEER-B-IN permit 20
  match ipv6 address prefix-list PEER-B-PREFIXES
  set community 65001:11111
!
route-map PEER-C-IN permit 10
  match ipv6 address prefix-list COMMON-PREFIXES
  set metric 200
route-map PEER-C-IN permit 20
  match ipv6 address prefix-list PEER-C-PREFIXES
  set community 65001:22222
!
route-map PEER-B-OUT permit 10
  match ipv6 address prefix-list PEER-A-PREFIXES
!
route-map PEER-C-OUT permit 10
  match ipv6 address prefix-list PEER-A-PREFIXES
!
line vty
!


Next: , Previous: Configuration of the BGP routers without Route Server, Up: Example of Route Server Configuration

11.3.2 Configuration of the BGP routers with Route Server

To convert the initial scenario into one with route server, first we must modify the configuration of routers RA, RB and RC. Now they must not peer between them, but only with the route server. For example, RA's configuration would turn into:

# Configuration for router 'RA'
!
hostname RA
password ****
!
router bgp 65001
  no bgp default ipv4-unicast
  neighbor 2001:0DB8::FFFF remote-as 65000
!
  address-family ipv6
    network 2001:0DB8:AAAA:1::/64
    network 2001:0DB8:AAAA:2::/64
    network 2001:0DB8:0000:1::/64
    network 2001:0DB8:0000:2::/64

    neighbor 2001:0DB8::FFFF activate
    neighbor 2001:0DB8::FFFF soft-reconfiguration inbound
  exit-address-family
!
line vty
!

Which is logically much simpler than its initial configuration, as it now maintains only one BGP peering and all the filters (route-maps) have disappeared.


Next: , Previous: Configuration of the BGP routers with Route Server, Up: Example of Route Server Configuration

11.3.3 Configuration of the Route Server itself

As we said when we described the functions of a route server (see Description of the Route Server model), it is in charge of all the route filtering. To achieve that, the In and Out filters from the RA, RB and RC configurations must be converted into Import and Export policies in the route server.

This is a fragment of the route server configuration (we only show the policies for client RA):

# Configuration for Route Server ('RS')
!
hostname RS
password ix
!
bgp multiple-instance
!
router bgp 65000 view RS
  no bgp default ipv4-unicast
  neighbor 2001:0DB8::A  remote-as 65001
  neighbor 2001:0DB8::B  remote-as 65002
  neighbor 2001:0DB8::C  remote-as 65003
!
  address-family ipv6
    neighbor 2001:0DB8::A activate
    neighbor 2001:0DB8::A route-server-client
    neighbor 2001:0DB8::A route-map RSCLIENT-A-IMPORT import
    neighbor 2001:0DB8::A route-map RSCLIENT-A-EXPORT export
    neighbor 2001:0DB8::A soft-reconfiguration inbound

    neighbor 2001:0DB8::B activate
    neighbor 2001:0DB8::B route-server-client
    neighbor 2001:0DB8::B route-map RSCLIENT-B-IMPORT import
    neighbor 2001:0DB8::B route-map RSCLIENT-B-EXPORT export
    neighbor 2001:0DB8::B soft-reconfiguration inbound

    neighbor 2001:0DB8::C activate
    neighbor 2001:0DB8::C route-server-client
    neighbor 2001:0DB8::C route-map RSCLIENT-C-IMPORT import
    neighbor 2001:0DB8::C route-map RSCLIENT-C-EXPORT export
    neighbor 2001:0DB8::C soft-reconfiguration inbound
  exit-address-family
!
ipv6 prefix-list COMMON-PREFIXES seq  5 permit 2001:0DB8:0000::/48 ge 64 le 64
ipv6 prefix-list COMMON-PREFIXES seq 10 deny any
!
ipv6 prefix-list PEER-A-PREFIXES seq  5 permit 2001:0DB8:AAAA::/48 ge 64 le 64
ipv6 prefix-list PEER-A-PREFIXES seq 10 deny any
!
ipv6 prefix-list PEER-B-PREFIXES seq  5 permit 2001:0DB8:BBBB::/48 ge 64 le 64
ipv6 prefix-list PEER-B-PREFIXES seq 10 deny any
!
ipv6 prefix-list PEER-C-PREFIXES seq  5 permit 2001:0DB8:CCCC::/48 ge 64 le 64
ipv6 prefix-list PEER-C-PREFIXES seq 10 deny any
!
route-map RSCLIENT-A-IMPORT permit 10
  match peer 2001:0DB8::B
  call A-IMPORT-FROM-B
route-map RSCLIENT-A-IMPORT permit 20
  match peer 2001:0DB8::C
  call A-IMPORT-FROM-C
!
route-map A-IMPORT-FROM-B permit 10
  match ipv6 address prefix-list COMMON-PREFIXES
  set metric 100
route-map A-IMPORT-FROM-B permit 20
  match ipv6 address prefix-list PEER-B-PREFIXES
  set community 65001:11111
!
route-map A-IMPORT-FROM-C permit 10
  match ipv6 address prefix-list COMMON-PREFIXES
  set metric 200
route-map A-IMPORT-FROM-C permit 20
  match ipv6 address prefix-list PEER-C-PREFIXES
  set community 65001:22222
!
route-map RSCLIENT-A-EXPORT permit 10
  match peer 2001:0DB8::B
  match ipv6 address prefix-list PEER-A-PREFIXES
route-map RSCLIENT-A-EXPORT permit 20
  match peer 2001:0DB8::C
  match ipv6 address prefix-list PEER-A-PREFIXES
!
...
...
...

If you compare the initial configuration of RA with the route server configuration above, you can see how easy it is to generate the Import and Export policies for RA from the In and Out route-maps of RA's original configuration.

When there was no route server, RA maintained two peerings, one with RB and another with RC. Each of this peerings had an In route-map configured. To build the Import route-map for client RA in the route server, simply add route-map entries following this scheme:

route-map <NAME> permit 10
    match peer <Peer Address>
    call <In Route-Map for this Peer>
route-map <NAME> permit 20
    match peer <Another Peer Address>
    call <In Route-Map for this Peer>

This is exactly the process that has been followed to generate the route-map RSCLIENT-A-IMPORT. The route-maps that are called inside it (A-IMPORT-FROM-B and A-IMPORT-FROM-C) are exactly the same than the In route-maps from the original configuration of RA (PEER-B-IN and PEER-C-IN), only the name is different.

The same could have been done to create the Export policy for RA (route-map RSCLIENT-A-EXPORT), but in this case the original Out route-maps where so simple that we decided not to use the call WORD commands, and we integrated all in a single route-map (RSCLIENT-A-EXPORT).

The Import and Export policies for RB and RC are not shown, but the process would be identical.


Previous: Configuration of the Route Server itself, Up: Example of Route Server Configuration

11.3.4 Further considerations about Import and Export route-maps

The current version of the route server patch only allows to specify a route-map for import and export policies, while in a standard BGP speaker apart from route-maps there are other tools for performing input and output filtering (access-lists, community-lists, ...). But this does not represent any limitation, as all kinds of filters can be included in import/export route-maps. For example suppose that in the non-route-server scenario peer RA had the following filters configured for input from peer B:

    neighbor 2001:0DB8::B prefix-list LIST-1 in
    neighbor 2001:0DB8::B filter-list LIST-2 in
    neighbor 2001:0DB8::B route-map PEER-B-IN in
    ...
    ...
route-map PEER-B-IN permit 10
  match ipv6 address prefix-list COMMON-PREFIXES
  set local-preference 100
route-map PEER-B-IN permit 20
  match ipv6 address prefix-list PEER-B-PREFIXES
  set community 65001:11111

It is posible to write a single route-map which is equivalent to the three filters (the community-list, the prefix-list and the route-map). That route-map can then be used inside the Import policy in the route server. Lets see how to do it:

    neighbor 2001:0DB8::A route-map RSCLIENT-A-IMPORT import
    ...
!
...
route-map RSCLIENT-A-IMPORT permit 10
  match peer 2001:0DB8::B
  call A-IMPORT-FROM-B
...
...
!
route-map A-IMPORT-FROM-B permit 1
  match ipv6 address prefix-list LIST-1
  match as-path LIST-2
  on-match goto 10
route-map A-IMPORT-FROM-B deny 2
route-map A-IMPORT-FROM-B permit 10
  match ipv6 address prefix-list COMMON-PREFIXES
  set local-preference 100
route-map A-IMPORT-FROM-B permit 20
  match ipv6 address prefix-list PEER-B-PREFIXES
  set community 65001:11111
!
...
...

The route-map A-IMPORT-FROM-B is equivalent to the three filters (LIST-1, LIST-2 and PEER-B-IN). The first entry of route-map A-IMPORT-FROM-B (sequence number 1) matches if and only if both the prefix-list LIST-1 and the filter-list LIST-2 match. If that happens, due to the “on-match goto 10” statement the next route-map entry to be processed will be number 10, and as of that point route-map A-IMPORT-FROM-B is identical to PEER-B-IN. If the first entry does not match, `on-match goto 10” will be ignored and the next processed entry will be number 2, which will deny the route.

Thus, the result is the same that with the three original filters, i.e., if either LIST-1 or LIST-2 rejects the route, it does not reach the route-map PEER-B-IN. In case both LIST-1 and LIST-2 accept the route, it passes to PEER-B-IN, which can reject, accept or modify the route.


Next: , Previous: Configuring Quagga as a Route Server, Up: Top

12 VTY shell

vtysh is integrated shell of Quagga software.

To use vtysh please specify —enable-vtysh to configure script. To use PAM for authentication use —with-libpam option to configure script.

vtysh only searches /etc/quagga path for vtysh.conf which is the vtysh configuration file. Vtysh does not search current directory for configuration file because the file includes user authentication settings.

Currently, vtysh.conf has only two commands.


Next: , Up: VTY shell

12.1 VTY shell username

— Command: username username nopassword

With this set, user foo does not need password authentication for user vtysh. With PAM vtysh uses PAM authentication mechanism.

If vtysh is compiled without PAM authentication, every user can use vtysh without authentication. vtysh requires read/write permission to the various daemons vty sockets, this can be accomplished through use of unix groups and the –enable-vty-group configure option.


Previous: VTY shell username, Up: VTY shell

12.2 VTY shell integrated configuration

— Command: service integrated-vtysh-config

Write out integrated Quagga.conf file when 'write file' is issued.

This command controls the behaviour of vtysh when it is told to write out the configuration. Per default, vtysh will instruct each daemon to write out their own config files when write file is issued. However, if service integrated-vtysh-config is set, when write file is issued, vtysh will instruct the daemons will write out a Quagga.conf with all daemons' commands integrated into it.

Vtysh per default behaves as if write-conf daemon is set. Note that both may be set at same time if one wishes to have both Quagga.conf and daemon specific files written out. Further, note that the daemons are hard-coded to first look for the integrated Quagga.conf file before looking for their own file.

We recommend you do not mix the use of the two types of files. Further, it is better not to use the integrated Quagga.conf file, as any syntax error in it can lead to /all/ of your daemons being unable to start up. Per daemon files are more robust as impact of errors in configuration are limited to the daemon in whose file the error is made.


Next: , Previous: VTY shell, Up: Top

13 Filtering

Quagga provides many very flexible filtering features. Filtering is used for both input and output of the routing information. Once filtering is defined, it can be applied in any direction.


Next: , Up: Filtering

13.1 IP Access List

— Command: access-list name permit ipv4-network
— Command: access-list name deny ipv4-network

Basic filtering is done by access-list as shown in the following example.

access-list filter deny 10.0.0.0/9
access-list filter permit 10.0.0.0/8


Previous: IP Access List, Up: Filtering

13.2 IP Prefix List

ip prefix-list provides the most powerful prefix based filtering mechanism. In addition to access-list functionality, ip prefix-list has prefix length range specification and sequential number specification. You can add or delete prefix based filters to arbitrary points of prefix-list using sequential number specification.

If no ip prefix-list is specified, it acts as permit. If ip prefix-list is defined, and no match is found, default deny is applied.

— Command: ip prefix-list name (permit|deny) prefix [le len] [ge len]
— Command: ip prefix-list name seq number (permit|deny) prefix [le len] [ge len]

You can create ip prefix-list using above commands.

seq
seq number can be set either automatically or manually. In the case that sequential numbers are set manually, the user may pick any number less than 4294967295. In the case that sequential number are set automatically, the sequential number will increase by a unit of five (5) per list. If a list with no specified sequential number is created after a list with a specified sequential number, the list will automatically pick the next multiple of five (5) as the list number. For example, if a list with number 2 already exists and a new list with no specified number is created, the next list will be numbered 5. If lists 2 and 7 already exist and a new list with no specified number is created, the new list will be numbered 10.
le
le command specifies prefix length. The prefix list will be applied if the prefix length is less than or equal to the le prefix length.
ge
ge command specifies prefix length. The prefix list will be applied if the prefix length is greater than or equal to the ge prefix length.

Less than or equal to prefix numbers and greater than or equal to prefix numbers can be used together. The order of the le and ge commands does not matter.

If a prefix list with a different sequential number but with the exact same rules as a previous list is created, an error will result. However, in the case that the sequential number and the rules are exactly similar, no error will result.

If a list with the same sequential number as a previous list is created, the new list will overwrite the old list.

Matching of IP Prefix is performed from the smaller sequential number to the larger. The matching will stop once any rule has been applied.

In the case of no le or ge command, the prefix length must match exactly the length specified in the prefix list.

— Command: no ip prefix-list name


Next: , Up: IP Prefix List

13.2.1 ip prefix-list description

— Command: ip prefix-list name description desc

Descriptions may be added to prefix lists. This command adds a description to the prefix list.

— Command: no ip prefix-list name description [desc]

Deletes the description from a prefix list. It is possible to use the command without the full description.


Next: , Previous: ip prefix-list description, Up: IP Prefix List

13.2.2 ip prefix-list sequential number control

— Command: ip prefix-list sequence-number

With this command, the IP prefix list sequential number is displayed. This is the default behavior.

— Command: no ip prefix-list sequence-number

With this command, the IP prefix list sequential number is not displayed.


Next: , Previous: ip prefix-list sequential number control, Up: IP Prefix List

13.2.3 Showing ip prefix-list

— Command: show ip prefix-list

Display all IP prefix lists.

— Command: show ip prefix-list name

Show IP prefix list can be used with a prefix list name.

— Command: show ip prefix-list name seq num

Show IP prefix list can be used with a prefix list name and sequential number.

— Command: show ip prefix-list name a.b.c.d/m

If the command longer is used, all prefix lists with prefix lengths equal to or longer than the specified length will be displayed. If the command first match is used, the first prefix length match will be displayed.

— Command: show ip prefix-list name a.b.c.d/m longer
— Command: show ip prefix-list name a.b.c.d/m first-match
— Command: show ip prefix-list summary
— Command: show ip prefix-list summary name
— Command: show ip prefix-list detail
— Command: show ip prefix-list detail name


Previous: Showing ip prefix-list, Up: IP Prefix List

13.2.4 Clear counter of ip prefix-list

— Command: clear ip prefix-list

Clears the counters of all IP prefix lists. Clear IP Prefix List can be used with a specified name and prefix.

— Command: clear ip prefix-list name
— Command: clear ip prefix-list name a.b.c.d/m


Next: , Previous: Filtering, Up: Top

14 Route Map

Route maps provide a means to both filter and/or apply actions to route, hence allowing policy to be applied to routes.

Route-maps are an ordered list of route-map entries. Each entry may specify up to four distincts sets of clauses:

Matching Policy
This specifies the policy implied if the ‘Matching Conditions’ are met or not met, and which actions of the route-map are to be taken, if any. The two possibilities are:

The ‘Matching Policy’ is specified as part of the command which defines the ordered entry in the route-map. See below.

Matching Conditions
A route-map entry may, optionally, specify one or more conditions which must be matched if the entry is to be considered further, as governed by the Match Policy. If a route-map entry does not explicitely specify any matching conditions, then it always matches.
Set Actions
A route-map entry may, optionally, specify one or more ‘Set Actions’ to set or modify attributes of the route.
Call Action
Call to another route-map, after any ‘Set Actions’ have been carried out. If the route-map called returns ‘deny’ then processing of the route-map finishes and the route is denied, regardless of the ‘Matching Policy’ or the ‘Exit Policy’. If the called route-map returns ‘permit’, then ‘Matching Policy’ and ‘Exit Policy’ govern further behaviour, as normal.
Exit Policy
An entry may, optionally, specify an alternative ‘Exit Policy’ to take if the entry matched, rather than the normal policy of exiting the route-map and permitting the route. The two possibilities are:

The default action of a route-map, if no entries match, is to deny. I.e. a route-map essentially has as its last entry an empty ‘deny’ entry, which matches all routes. To change this behaviour, one must specify an empty ‘permit’ entry as the last entry in the route-map.

To summarise the above:

Match No Match
Permit action cont
Deny deny cont

action

deny

cont


Next: , Up: Route Map

14.1 Route Map Command

— Command: route-map route-map-name (permit|deny) order

Configure the order'th entry in route-map-name with ‘Match Policy’ of either permit or deny.


Next: , Previous: Route Map Command, Up: Route Map

14.2 Route Map Match Command

— Route-map Command: match ip address access_list

Matches the specified access_list

— Route-map Command: match ip next-hop ipv4_addr

Matches the specified ipv4_addr.

— Route-map Command: match aspath as_path

Matches the specified as_path.

— Route-map Command: match metric metric

Matches the specified metric.

— Route-map Command: match community community_list

Matches the specified community_list


Next: , Previous: Route Map Match Command, Up: Route Map

14.3 Route Map Set Command

— Route-map Command: set ip next-hop ipv4_address

Set the BGP nexthop address.

— Route-map Command: set local-preference local_pref

Set the BGP local preference.

— Route-map Command: set weight weight

Set the route's weight.

— Route-map Command: set metric metric

Set the BGP attribute MED.

— Route-map Command: set as-path prepend as_path

Set the BGP AS path to prepend.

— Route-map Command: set community community

Set the BGP community attribute.

— Route-map Command: set ipv6 next-hop global ipv6_address

Set the BGP-4+ global IPv6 nexthop address.

— Route-map Command: set ipv6 next-hop local ipv6_address

Set the BGP-4+ link local IPv6 nexthop address.


Next: , Previous: Route Map Set Command, Up: Route Map

14.4 Route Map Call Command

— Route-map Command: call name

Call route-map name. If it returns deny, deny the route and finish processing the route-map.


Next: , Previous: Route Map Call Command, Up: Route Map

14.5 Route Map Exit Action Command

— Route-map Command: on-match next
— Route-map Command: continue

Proceed on to the next entry in the route-map.

— Route-map Command: on-match goto N
— Route-map Command: continue N

Proceed processing the route-map at the first entry whose order is >= N


Previous: Route Map Exit Action Command, Up: Route Map

14.6 Route Map Examples

A simple example of a route-map:

route-map test permit 10
 match ip address 10
 set local-preference 200

This means that if a route matches ip access-list number 10 it's local-preference value is set to 200.

See BGP Configuration Examples for examples of more sophisticated useage of route-maps, including of the ‘call’ action.


Next: , Previous: Route Map, Up: Top

15 IPv6 Support

Quagga fully supports IPv6 routing. As described so far, Quagga supports RIPng, OSPFv3, Babel and BGP-4+. You can give IPv6 addresses to an interface and configure static IPv6 routing information. Quagga IPv6 also provides automatic address configuration via a feature called address auto configuration. To do it, the router must send router advertisement messages to the all nodes that exist on the network.


Up: IPv6 Support

15.1 Router Advertisement

— Interface Command: no ipv6 nd suppress-ra

Send router advertisment messages.

— Interface Command: ipv6 nd suppress-ra

Don't send router advertisment messages.

— Interface Command: ipv6 nd prefix ipv6prefix [valid-lifetime] [preferred-lifetime] [off-link] [no-autoconfig] [router-address]

Configuring the IPv6 prefix to include in router advertisements. Several prefix specific optional parameters and flags may follow:

— Interface Command: ipv6 nd ra-interval <1-1800>
— Interface Command: no ipv6 nd ra-interval [<1-1800>]

The maximum time allowed between sending unsolicited multicast router advertisements from the interface, in seconds.

Default: 600

— Interface Command: ipv6 nd ra-interval msec <70-1800000>
— Interface Command: no ipv6 nd ra-interval [msec <70-1800000>]

The maximum time allowed between sending unsolicited multicast router advertisements from the interface, in milliseconds.

Default: 600000

— Interface Command: ipv6 nd ra-lifetime <0-9000>
— Interface Command: no ipv6 nd ra-lifetime [<0-9000>]

The value to be placed in the Router Lifetime field of router advertisements sent from the interface, in seconds. Indicates the usefulness of the router as a default router on this interface. Setting the value to zero indicates that the router should not be considered a default router on this interface. Must be either zero or between value specified with ipv6 nd ra-interval (or default) and 9000 seconds.

Default: 1800

— Interface Command: ipv6 nd reachable-time <1-3600000>
— Interface Command: no ipv6 nd reachable-time [<1-3600000>]

The value to be placed in the Reachable Time field in the Router Advertisement messages sent by the router, in milliseconds. The configured time enables the router to detect unavailable neighbors. The value zero means unspecified (by this router).

Default: 0

— Interface Command: ipv6 nd managed-config-flag
— Interface Command: no ipv6 nd managed-config-flag

Set/unset flag in IPv6 router advertisements which indicates to hosts that they should use managed (stateful) protocol for addresses autoconfiguration in addition to any addresses autoconfigured using stateless address autoconfiguration.

Default: not set

— Interface Command: ipv6 nd other-config-flag
— Interface Command: no ipv6 nd other-config-flag

Set/unset flag in IPv6 router advertisements which indicates to hosts that they should use administered (stateful) protocol to obtain autoconfiguration information other than addresses.

Default: not set

— Interface Command: ipv6 nd home-agent-config-flag
— Interface Command: no ipv6 nd home-agent-config-flag

Set/unset flag in IPv6 router advertisements which indicates to hosts that the router acts as a Home Agent and includes a Home Agent Option.

Default: not set

— Interface Command: ipv6 nd home-agent-preference <0-65535>
— Interface Command: no ipv6 nd home-agent-preference [<0-65535>]

The value to be placed in Home Agent Option, when Home Agent config flag is set, which indicates to hosts Home Agent preference. The default value of 0 stands for the lowest preference possible.

Default: 0

+

— Interface Command: ipv6 nd home-agent-lifetime <0-65520>

+ — Interface Command: no ipv6 nd home-agent-lifetime [<0-65520>]

The value to be placed in Home Agent Option, when Home Agent config flag is set, which indicates to hosts Home Agent Lifetime. The default value of 0 means to place the current Router Lifetime value.

Default: 0

— Interface Command: ipv6 nd adv-interval-option
— Interface Command: no ipv6 nd adv-interval-option

Include an Advertisement Interval option which indicates to hosts the maximum time, in milliseconds, between successive unsolicited Router Advertisements.

Default: not set

— Interface Command: ipv6 nd router-preference (high|medium|low)
— Interface Command: no ipv6 nd router-preference [(high|medium|low)]

Set default router preference in IPv6 router advertisements per RFC4191.

Default: medium

— Interface Command: ipv6 nd mtu <1-65535>
— Interface Command: no ipv6 nd mtu [<1-65535>]

Include an MTU (type 5) option in each RA packet to assist the attached hosts in proper interface configuration. The announced value is not verified to be consistent with router interface MTU.

Default: don't advertise any MTU option

interface eth0
 no ipv6 nd suppress-ra
 ipv6 nd prefix 2001:0DB8:5009::/64

For more information see RFC2462 (IPv6 Stateless Address Autoconfiguration) , RFC4861 (Neighbor Discovery for IP Version 6 (IPv6)) , RFC6275 (Mobility Support in IPv6) and RFC4191 (Default Router Preferences and More-Specific Routes).


Next: , Previous: IPv6 Support, Up: Top

16 Kernel Interface

There are several different methods for reading kernel routing table information, updating kernel routing tables, and for looking up interfaces.

ioctl
The ‘ioctl’ method is a very traditional way for reading or writing kernel information. ‘ioctl’ can be used for looking up interfaces and for modifying interface addresses, flags, mtu settings and other types of information. Also, ‘ioctl’ can insert and delete kernel routing table entries. It will soon be available on almost any platform which zebra supports, but it is a little bit ugly thus far, so if a better method is supported by the kernel, zebra will use that.
sysctl
sysctl’ can lookup kernel information using MIB (Management Information Base) syntax. Normally, it only provides a way of getting information from the kernel. So one would usually want to change kernel information using another method such as ‘ioctl’.
proc filesystem
proc filesystem’ provides an easy way of getting kernel information.
routing socket
netlink
On recent Linux kernels (2.0.x and 2.2.x), there is a kernel/user communication support called netlink. It makes asynchronous communication between kernel and Quagga possible, similar to a routing socket on BSD systems.

Before you use this feature, be sure to select (in kernel configuration) the kernel/netlink support option 'Kernel/User network link driver' and 'Routing messages'.

Today, the /dev/route special device file is obsolete. Netlink communication is done by reading/writing over netlink socket.

After the kernel configuration, please reconfigure and rebuild Quagga. You can use netlink as a dynamic routing update channel between Quagga and the kernel.


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17 SNMP Support

SNMP (Simple Network Managing Protocol) is a widely implemented feature for collecting network information from router and/or host. Quagga itself does not support SNMP agent (server daemon) functionality but is able to connect to a SNMP agent using the SMUX protocol (RFC1227) and make the routing protocol MIBs available through it.


Next: , Up: SNMP Support

17.1 Getting and installing an SNMP agent

There are several SNMP agent which support SMUX. We recommend to use the latest version of net-snmp which was formerly known as ucd-snmp. It is free and open software and available at http://www.net-snmp.org/ and as binary package for most Linux distributions. net-snmp has to be compiled with --with-mib-modules=smux to be able to accept connections from Quagga.


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17.2 SMUX configuration

To enable SMUX protocol support, Quagga must have been build with the --enable-snmp option.

A separate connection has then to be established between between the SNMP agent (snmpd) and each of the Quagga daemons. This connections each use different OID numbers and passwords. Be aware that this OID number is not the one that is used in queries by clients, it is solely used for the intercommunication of the daemons.

In the following example the ospfd daemon will be connected to the snmpd daemon using the password "quagga_ospfd". For testing it is recommending to take exactly the below snmpd.conf as wrong access restrictions can be hard to debug.

/etc/snmp/snmpd.conf:
	#
	# example access restrictions setup
	#
	com2sec readonly default public
	group MyROGroup v1 readonly
	view all included .1 80
	access MyROGroup "" any noauth exact all none none
	#
	# the following line is relevant for Quagga
	#
	smuxpeer .1.3.6.1.4.1.3317.1.2.5 quagga_ospfd

/etc/quagga/ospf:
	! ... the rest of ospfd.conf has been omitted for clarity ...
	!
	smux peer .1.3.6.1.4.1.3317.1.2.5 quagga_ospfd
	!

After restarting snmpd and quagga, a successful connection can be verified in the syslog and by querying the SNMP daemon:

snmpd[12300]: [smux_accept] accepted fd 12 from 127.0.0.1:36255
snmpd[12300]: accepted smux peer: \
	oid GNOME-PRODUCT-ZEBRA-MIB::ospfd, quagga-0.96.5

# snmpwalk -c public -v1 localhost .1.3.6.1.2.1.14.1.1
OSPF-MIB::ospfRouterId.0 = IpAddress: 192.168.42.109

Be warned that the current version (5.1.1) of the Net-SNMP daemon writes a line for every SNMP connect to the syslog which can lead to enormous log file sizes. If that is a problem you should consider to patch snmpd and comment out the troublesome snmp_log() line in the function netsnmp_agent_check_packet() in agent/snmp_agent.c.


Next: , Previous: SMUX configuration, Up: SNMP Support

17.3 MIB and command reference

The following OID numbers are used for the interprocess communication of snmpd and the Quagga daemons. Sadly, SNMP has not been implemented in all daemons yet.

            (OIDs below .iso.org.dod.internet.private.enterprises)
zebra	.1.3.6.1.4.1.3317.1.2.1 .gnome.gnomeProducts.zebra.zserv
bgpd	.1.3.6.1.4.1.3317.1.2.2 .gnome.gnomeProducts.zebra.bgpd
ripd	.1.3.6.1.4.1.3317.1.2.3 .gnome.gnomeProducts.zebra.ripd
ospfd	.1.3.6.1.4.1.3317.1.2.5 .gnome.gnomeProducts.zebra.ospfd
ospf6d	.1.3.6.1.4.1.3317.1.2.6 .gnome.gnomeProducts.zebra.ospf6d

The following OID numbers are used for querying the SNMP daemon by a client:

zebra	.1.3.6.1.2.1.4.24   .iso.org.dot.internet.mgmt.mib-2.ip.ipForward
ospfd	.1.3.6.1.2.1.14	    .iso.org.dot.internet.mgmt.mib-2.ospf
bgpd	.1.3.6.1.2.1.15	    .iso.org.dot.internet.mgmt.mib-2.bgp
ripd	.1.3.6.1.2.1.23	    .iso.org.dot.internet.mgmt.mib-2.rip2
ospf6d	.1.3.6.1.3.102	    .iso.org.dod.internet.experimental.ospfv3

The following syntax is understood by the Quagga daemons for configuring SNMP:

— Command: smux peer oid
— Command: no smux peer oid
— Command: smux peer oid password
— Command: no smux peer oid password


Previous: MIB and command reference, Up: SNMP Support

17.4 Handling SNMP Traps

To handle snmp traps make sure your snmp setup of quagga works correctly as described in the quagga documentation in See SNMP Support.

The BGP4 mib will send traps on peer up/down events. These should be visible in your snmp logs with a message similar to:

snmpd[13733]: Got trap from peer on fd 14

To react on these traps they should be handled by a trapsink. Configure your trapsink by adding the following lines to /etc/snmpd/snmpd.conf:

  # send traps to the snmptrapd on localhost
  trapsink localhost

This will send all traps to an snmptrapd running on localhost. You can of course also use a dedicated management station to catch traps. Configure the snmptrapd daemon by adding the following line to /etc/snmpd/snmptrapd.conf:

  traphandle .1.3.6.1.4.1.3317.1.2.2 /etc/snmp/snmptrap_handle.sh

This will use the bash script /etc/snmp/snmptrap_handle.sh to handle the BGP4 traps. To add traps for other protocol daemons, lookup their appropriate OID from their mib. (For additional information about which traps are supported by your mib, lookup the mib on http://www.oidview.com/mibs/detail.html).

Make sure snmptrapd is started.

The snmptrap_handle.sh script I personally use for handling BGP4 traps is below. You can of course do all sorts of things when handling traps, like sound a siren, have your display flash, etc., be creative ;).

  #!/bin/bash

  # routers name
  ROUTER=`hostname -s`

  #email address use to sent out notification
  EMAILADDR="john@doe.com"
  #email address used (allongside above) where warnings should be sent
  EMAILADDR_WARN="sms-john@doe.com"

  # type of notification
  TYPE="Notice"

  # local snmp community for getting AS belonging to peer
  COMMUNITY="<community>"

  # if a peer address is in $WARN_PEERS a warning should be sent
  WARN_PEERS="192.0.2.1"


  # get stdin
  INPUT=`cat -`

  # get some vars from stdin
  uptime=`echo $INPUT | cut -d' ' -f5`
  peer=`echo $INPUT | cut -d' ' -f8 | sed -e 's/SNMPv2-SMI::mib-2.15.3.1.14.//g'`
  peerstate=`echo $INPUT | cut -d' ' -f13`
  errorcode=`echo $INPUT | cut -d' ' -f9 | sed -e 's/\"//g'`
  suberrorcode=`echo $INPUT | cut -d' ' -f10 | sed -e 's/\"//g'`
  remoteas=`snmpget -v2c -c $COMMUNITY localhost SNMPv2-SMI::mib-2.15.3.1.9.$peer | cut -d' ' -f4`

  WHOISINFO=`whois -h whois.ripe.net " -r AS$remoteas" | egrep '(as-name|descr)'`
  asname=`echo "$WHOISINFO" | grep "^as-name:" | sed -e 's/^as-name://g' -e 's/  //g' -e 's/^ //g' | uniq`
  asdescr=`echo "$WHOISINFO" | grep "^descr:" | sed -e 's/^descr://g' -e 's/  //g' -e 's/^ //g' | uniq`

  # if peer address is in $WARN_PEER, the email should also
  # be sent to $EMAILADDR_WARN
  for ip in $WARN_PEERS; do
    if [ "x$ip" == "x$peer" ]; then
      EMAILADDR="$EMAILADDR,$EMAILADDR_WARN"
      TYPE="WARNING"
      break
    fi
  done
  

  # convert peer state
  case "$peerstate" in
    1) peerstate="Idle" ;;
    2) peerstate="Connect" ;;
    3) peerstate="Active" ;;
    4) peerstate="Opensent" ;;
    5) peerstate="Openconfirm" ;;
    6) peerstate="Established" ;;
    *) peerstate="Unknown" ;;
  esac

  # get textual messages for errors
  case "$errorcode" in
    00)
      error="No error"
      suberror=""
      ;;
    01)
      error="Message Header Error"
      case "$suberrorcode" in
        01) suberror="Connection Not Synchronized" ;;
        02) suberror="Bad Message Length" ;;
        03) suberror="Bad Message Type" ;;
        *) suberror="Unknown" ;;
      esac
      ;;
    02)    
      error="OPEN Message Error"
      case "$suberrorcode" in
        01) suberror="Unsupported Version Number" ;;
        02) suberror="Bad Peer AS" ;;
        03) suberror="Bad BGP Identifier" ;;
        04) suberror="Unsupported Optional Parameter" ;;
        05) suberror="Authentication Failure" ;;
        06) suberror="Unacceptable Hold Time" ;;
        *) suberror="Unknown" ;;
      esac
      ;;
    03)
      error="UPDATE Message Error"
      case "$suberrorcode" in
        01) suberror="Malformed Attribute List" ;;
        02) suberror="Unrecognized Well-known Attribute" ;;
        03) suberror="Missing Well-known Attribute" ;;
        04) suberror="Attribute Flags Error" ;;
        05) suberror="Attribute Length Error" ;;
        06) suberror="Invalid ORIGIN Attribute" ;;
        07) suberror="AS Routing Loop" ;;
        08) suberror="Invalid NEXT_HOP Attribute" ;;
        09) suberror="Optional Attribute Error" ;;
        10) suberror="Invalid Network Field" ;;
        11) suberror="Malformed AS_PATH" ;;
        *) suberror="Unknown" ;;
      esac
      ;;
    04)
      error="Hold Timer Expired"
      suberror=""
      ;;
    05)
      error="Finite State Machine Error"
      suberror=""
      ;;
    06)
      error="Cease"
      case "$suberrorcode" in
        01) suberror="Maximum Number of Prefixes Reached" ;;
        02) suberror="Administratively Shutdown" ;;
        03) suberror="Peer Unconfigured" ;;
        04) suberror="Administratively Reset" ;;
        05) suberror="Connection Rejected" ;;
        06) suberror="Other Configuration Change" ;;
        07) suberror="Connection collision resolution" ;;
        08) suberror="Out of Resource" ;;
        09) suberror="MAX" ;;
        *) suberror="Unknown" ;;
      esac
      ;;
    *)
      error="Unknown"
      suberror=""
      ;;
  esac

  # create textual message from errorcodes
  if [ "x$suberror" == "x" ]; then
    NOTIFY="$errorcode ($error)"
  else
    NOTIFY="$errorcode/$suberrorcode ($error/$suberror)"
  fi
 

  # form a decent subject
  SUBJECT="$TYPE: $ROUTER [bgp] $peer is $peerstate: $NOTIFY"
  # create the email body
  MAIL=`cat << EOF
  BGP notification on router $ROUTER.
  
  Peer: $peer
  AS: $remoteas
  New state: $peerstate
  Notification: $NOTIFY

  Info:
  $asname
  $asdescr
 
  Snmpd uptime: $uptime
  EOF`

  # mail the notification
  echo "$MAIL" | mail -s "$SUBJECT" $EMAILADDR


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Appendix A Zebra Protocol

A.1 Overview of the Zebra Protocol

Zebra Protocol is used by protocol daemons to communicate with the zebra daemon.

Each protocol daemon may request and send information to and from the zebra daemon such as interface states, routing state, nexthop-validation, and so on. Protocol daemons may also install routes with zebra. The zebra daemon manages which route is installed into the forwarding table with the kernel.

Zebra Protocol is a streaming protocol, with a common header. Two versions of the header are in use. Version 0 is implicitely versioned. Version 1 has an explicit version field. Version 0 can be distinguished from all other versions by examining the 3rd byte of the header, which contains a marker value for all versions bar version 0. The marker byte corresponds to the command field in version 0, and the marker value is a reserved command in version 0.

We do not anticipate there will be further versions of the header for the foreseeable future, as the command field in version 1 is wide enough to allow for future extensions to done compatibly through seperate commands.

Version 0 is used by all versions of GNU Zebra as of this writing, and versions of Quagga up to and including Quagga 0.98. Version 1 will be used as of Quagga 1.0.

A.2 Zebra Protocol Definition

A.2.1 Zebra Protocol Header (version 0)

0                   1                   2                   3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-------------------------------+---------------+
|           Length (2)          |   Command (1) |
+-------------------------------+---------------+

A.2.2 Zebra Protocol Common Header (version 1)

0                   1                   2                   3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-------------------------------+---------------+-------------+
|           Length (2)          |   Marker (1)  | Version (1) |
+-------------------------------+---------------+-------------+
|          Command (2)          |
+-------------------------------+

A.2.3 Zebra Protocol Header Field Definitions

Length
Total packet length including this header. The minimum length is 3 bytes for version 0 messages and 6 bytes for version 1 messages.
Marker
Static marker with a value of 255 always. This is to allow version 0 Zserv headers (which do not include version explicitely) to be distinguished from versioned headers. Not present in version 0 messages.
Version
Version number of the Zserv message. Clients should not continue processing messages past the version field for versions they do not recognise. Not present in version 0 messages.
Command
The Zebra Protocol command.

A.2.4 Zebra Protocol Commands

Command Value
ZEBRA_INTERFACE_ADD 1
ZEBRA_INTERFACE_DELETE 2
ZEBRA_INTERFACE_ADDRESS_ADD 3
ZEBRA_INTERFACE_ADDRESS_DELETE 4
ZEBRA_INTERFACE_UP 5
ZEBRA_INTERFACE_DOWN 6
ZEBRA_IPV4_ROUTE_ADD 7
ZEBRA_IPV4_ROUTE_DELETE 8
ZEBRA_IPV6_ROUTE_ADD 9
ZEBRA_IPV6_ROUTE_DELETE 10
ZEBRA_REDISTRIBUTE_ADD 11
ZEBRA_REDISTRIBUTE_DELETE 12
ZEBRA_REDISTRIBUTE_DEFAULT_ADD 13
ZEBRA_REDISTRIBUTE_DEFAULT_DELETE 14
ZEBRA_IPV4_NEXTHOP_LOOKUP 15
ZEBRA_IPV6_NEXTHOP_LOOKUP 16


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Appendix B Packet Binary Dump Format

Quagga can dump routing protocol packet into file with a binary format (see Dump BGP packets and table).

It seems to be better that we share the MRT's header format for backward compatibility with MRT's dump logs. We should also define the binary format excluding the header, because we must support both IP v4 and v6 addresses as socket addresses and / or routing entries.

In the last meeting, we discussed to have a version field in the header. But Masaki told us that we can define new `type' value rather than having a `version' field, and it seems to be better because we don't need to change header format.

Here is the common header format. This is same as that of MRT.

0                   1                   2                   3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                              Time                             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Type              |            Subtype            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                             Length                            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

If `type' is PROTOCOL_BGP4MP, `subtype' is BGP4MP_STATE_CHANGE, and Address Family == IP (version 4)

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Source AS number       |     Destination AS number     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Interface Index        |      Address Family           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address                    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|            Old State          |           New State           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where State is the value defined in RFC1771.

If `type' is PROTOCOL_BGP4MP, `subtype' is BGP4MP_STATE_CHANGE, and Address Family == IP version 6

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Source AS number       |     Destination AS number     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Interface Index        |      Address Family           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address (Cont'd)             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address (Cont'd)             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address (Cont'd)             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address                    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address (Cont'd)           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address (Cont'd)           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address (Cont'd)           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|            Old State          |           New State           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

If `type' is PROTOCOL_BGP4MP, `subtype' is BGP4MP_MESSAGE, and Address Family == IP (version 4)

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Source AS number       |     Destination AS number     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Interface Index        |      Address Family           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address                    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                       BGP Message Packet                      |
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where BGP Message Packet is the whole contents of the BGP4 message including header portion.

If `type' is PROTOCOL_BGP4MP, `subtype' is BGP4MP_MESSAGE, and Address Family == IP version 6

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Source AS number       |     Destination AS number     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|        Interface Index        |      Address Family           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address                      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address (Cont'd)             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address (Cont'd)             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Source IP address (Cont'd)             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address                    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address (Cont'd)           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address (Cont'd)           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                     Destination IP address (Cont'd)           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                       BGP Message Packet                      |
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

If `type' is PROTOCOL_BGP4MP, `subtype' is BGP4MP_ENTRY, and Address Family == IP (version 4)

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|            View #             |            Status             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Time Last Change                       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|       Address Family          |    SAFI       | Next-Hop-Len  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Next Hop Address                       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prefix Length |             Address Prefix [variable]         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|       Attribute Length        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|      BGP Attribute [variable length]    			|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

If `type' is PROTOCOL_BGP4MP, `subtype' is BGP4MP_ENTRY, and Address Family == IP version 6

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|            View #             |            Status             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Time Last Change                       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|       Address Family          |    SAFI       | Next-Hop-Len  |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Next Hop Address                       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Next Hop Address (Cont'd)              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Next Hop Address (Cont'd)              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        Next Hop Address (Cont'd)              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Prefix Length |             Address Prefix [variable]         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Address Prefix (cont'd) [variable]        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|       Attribute Length        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|      BGP Attribute [variable length]    			    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

BGP4 Attribute must not contain MP_UNREACH_NLRI. If BGP Attribute has MP_REACH_NLRI field, it must has zero length NLRI, e.g., MP_REACH_NLRI has only Address Family, SAFI and next-hop values.

If `type' is PROTOCOL_BGP4MP and `subtype' is BGP4MP_SNAPSHOT,

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           View #              |       File Name [variable]    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The file specified in "File Name" contains all routing entries, which are in the format of “subtype == BGP4MP_ENTRY”.

Constants:
  /* type value */
  #define MSG_PROTOCOL_BGP4MP 16
  /* subtype value */
  #define BGP4MP_STATE_CHANGE 0
  #define BGP4MP_MESSAGE 1
  #define BGP4MP_ENTRY 2
  #define BGP4MP_SNAPSHOT 3


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Command Index


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VTY Key Index


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Index


Footnotes

[1] gnu/Linux has very flexible kernel configuration features