ripd.texi

大名鼎鼎的路由器源码。程序分ZEBRA、OSPFRIP等3个包。程序框架采用一个路由协议一个进程的方式

@c -*-texinfo-*-
@c This is part of the GNU Zebra Manual.
@c Copyright (C) 1999, 2000 Kunihiro Ishiguro
@c See file zebra.texi for copying conditions.
@node RIP
@comment  node-name,  next,  previous,  up
@chapter 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 @dfn{distance-vector} protocol and is
based on the @dfn{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.

@command{ripd} supports RIP version 2 as described in RFC2453 and RIP
version 1 as described in RFC1058.

@menu
* Starting and Stopping ripd::  
* RIP Configuration::           
* How to Announce RIP route::   
* Filtering RIP Routes::        
* RIP Metric Manipulation::     
* RIP distance::                
* RIP route-map::               
* RIP Authentication::          
* RIP Timers::                  
* Show RIP Information::        
* RIP Debug Commands::          
@end menu

@node Starting and Stopping ripd, RIP Configuration, RIP, RIP
@comment  node-name,  next,  previous,  up
@section Starting and Stopping ripd

The default configuration file name of @command{ripd}'s is
@file{ripd.conf}.  When invocation @command{ripd} searches directory
@value{INSTALL_PREFIX_ETC}.  If @file{ripd.conf} is not there next
search current directory.

RIP uses UDP port 521 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 @command{zebra} daemon.  So running @command{zebra}
is mandatory to run @command{ripd}.  Thus minimum sequence for running
RIP is like below:

@example
@group
# zebra -d
# ripd -d
@end group
@end example

Please note that @command{zebra} must be invoked before @command{ripd}.

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

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

@command{ripd} invocation options.  Common options that can be specified
(@pxref{Common Invocation Options}).

@table @samp
@item -r
@itemx --retain
When the program terminates, retain routes added by @command{ripd}.
@end table

@menu
* RIP netmask::                 
@end menu

@node RIP netmask,  , Starting and Stopping ripd, Starting and Stopping ripd
@comment  node-name,  next,  previous,  up
@subsection RIP netmask

The netmask features of @command{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.  Zebra @command{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.


@node RIP Configuration, How to Announce RIP route, Starting and Stopping ripd, RIP
@comment  node-name,  next,  previous,  up
@section RIP Configuration

@deffn Command {router rip} {}
The @code{router rip} command is necessary to enable RIP.  To disable
RIP, use the @code{no router rip} command.  RIP must be enabled before
carrying out any of the RIP commands.
@end deffn

@deffn Command {no rouer rip} {}
Disable RIP.
@end deffn

RIP can be configured to process either Version 1 or Version 2 packets,
the default mode is Version 2.  If no version is specified, then the RIP
daemon will default to Version 2.  If RIP is set to Version
1, the setting "Version 1" will be displayed, but the setting "Version
2" will not be displayed whether or not Version 2 is set explicitly as
the version of RIP being used.

@deffn {RIP Command} {network @var{network}} {}
@deffnx {RIP Command} {no network @var{network}} {}
Set the RIP enable interface by @var{network}.  The interfaces which
have addresses matching with @var{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 @code{no
network} command will disable RIP for the specified network.
@end deffn

@deffn {RIP Command} {network @var{ifname}} {}
@deffnx {RIP Command} {no network @var{ifname}} {}
Set a RIP enabled interface by @var{ifname}.  Both the sending and
receiving of RIP packets will be enabled on the port specified in the
@code{network ifname} command.  The @code{no network ifname} command will disable
RIP on the specified interface.
@end deffn

@deffn {RIP Command} {neighbor @var{a.b.c.d}} {}
@deffnx {RIP Command} {no neighbor @var{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 @code{no
neighbor a.b.c.d} command will disable the RIP neighbor.
@end deffn

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

@example
@group
!
router rip
 network 10.0.0.0/8
 network eth0
!
@end group
@end example

Passive interface

@deffn {RIP command} {passive-interface @var{IFNAME}} {}
@deffnx {RIP command} {no passive-interface @var{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 @code{neighbor} command.
@end deffn

RIP version handling

@deffn {RIP Command} {version @var{version}} {}
Set RIP process's version.  @var{version} can be ``1'' or ``2''.
@end deffn

@deffn {Interface command} {ip rip send version @var{version}} {}
@var{version} can be `1', `2', `1 2'.  This configuration command
overrides the router's rip version setting.  The command will enable the
selected interface to send packets with RIP Version 1, RIP Version 2, or
both.  In the case of '1 2', packets will be both broadcast and
multicast.
@end deffn

@deffn {Interface command} {ip rip receive version @var{version}} {}
Version setting for incoming RIP packets.  This command will enable the
selected interface to receive packets in RIP Version 1, RIP Version 2,
or both.
@end deffn

RIP split-horizon

@deffn {Interface command} {ip split-horizon} {}
@deffnx {Interface command} {no ip split-horizon} {}
Control split-horizon on the interface.  Default is @code{ip
split-horizon}.  If you don't perform split-horizon on the interface,
please specify @code{no ip split-horizon}.
@end deffn

@node How to Announce RIP route, Filtering RIP Routes, RIP Configuration, RIP
@comment  node-name,  next,  previous,  up
@section How to Announce RIP route

@deffn {RIP command} {redistribute kernel} {}
@deffnx {RIP command} {redistribute kernel metric <0-16>} {}
@deffnx {RIP command} {redistribute kernel route-map @var{route-map}} {}
@deffnx {RIP command} {no redistribute kernel} {}
@code{redistribute kernel} redistributes routing information from
kernel route entries into the RIP tables. @code{no redistribute kernel}
disables the routes.
@end deffn

@deffn {RIP command} {redistribute static} {}
@deffnx {RIP command} {redistribute static metric <0-16>} {}
@deffnx {RIP command} {redistribute static route-map @var{route-map}} {}
@deffnx {RIP command} {no redistribute static} {}
@code{redistribute static} redistributes routing information from
static route entries into the RIP tables. @code{no redistribute static}
disables the routes.
@end deffn

@deffn {RIP command} {redistribute connected} {}
@deffnx {RIP command} {redistribute connected metric <0-16>} {}
@deffnx {RIP command} {redistribute connected route-map @var{route-map}} {}
@deffnx {RIP command} {no redistribute connected} {}
Redistribute connected routes into the RIP tables.  @code{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.
@end deffn

@deffn {RIP command} {redistribute ospf} {}
@deffnx {RIP command} {redistribute ospf metric <0-16>} {}
@deffnx {RIP command} {redistribute ospf route-map @var{route-map}} {}
@deffnx {RIP command} {no redistribute ospf} {}
@code{redistribute ospf} redistributes routing information from
ospf route entries into the RIP tables. @code{no redistribute ospf}
disables the routes.
@end deffn

@deffn {RIP command} {redistribute bgp} {}
@deffnx {RIP command} {redistribute bgp metric <0-16>} {}
@deffnx {RIP command} {redistribute bgp route-map @var{route-map}} {}
@deffnx {RIP command} {no redistribute bgp} {}
@code{redistribute bgp} redistributes routing information from
bgp route entries into the RIP tables. @code{no redistribute bgp}
disables the routes.
@end deffn

If you want to specify RIP only static routes:

@deffn {RIP command} {default-information originate} {}
@end deffn

@deffn {RIP command} {route @var{a.b.c.d/m}} {}
@deffnx {RIP command} {no route @var{a.b.c.d/m}} {}
This command is specific to Zebra.  The @code{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 Zebra and
redistributing it in RIP using @code{redistribute static}.
@end deffn


@node  Filtering RIP Routes, RIP Metric Manipulation, How to Announce RIP route, RIP
@comment  node-name,  next,  previous,  up
@section Filtering RIP Routes

RIP routes can be filtered by a distribute-list.

@deffn Command {distribute-list @var{access_list} @var{direct} @var{ifname}} {}
You can apply access lists to the interface with a @code{distribute-list}
command.  @var{access_list} is the access list name.  @var{direct} is
@samp{in} or @samp{out}.  If @var{direct} is @samp{in} the access list
is applied to input packets.

The @code{distribute-list} command can be used to filter the RIP path.
@code{distribute-list} can apply access-lists to a chosen interface.