@c -*-texinfo-*-
@c This is part of the Frr Manual.
@c @value{COPYRIGHT_STR}
@c See file frr.texi for copying conditions.
@node EIGRP
@chapter EIGRP

EIGRP -- Routing Information Protocol is widely deployed interior gateway
routing protocol.  EIGRP was developed in the 1990's.  EIGRP is a
@dfn{distance-vector} protocol and is based on the @dfn{dual} algorithms.
As a distance-vector protocol, the EIGRP router send updates to its
neighbors as networks change, thus allowing the convergence to a
known topology.

@command{eigrpd} supports EIGRP as described in RFC7868

@menu
* Starting and Stopping eigrpd::
* EIGRP Configuration::
* How to Announce EIGRP routes::
* Show EIGRP Information::
* EIGRP Debug Commands::
@end menu

@node Starting and Stopping eigrpd
@section Starting and Stopping eigrpd

The default configuration file name of @command{eigrpd}'s is
@file{eigrpd.conf}.  When invocation @command{eigrpd} searches directory
@value{INSTALL_PREFIX_ETC}.  If @file{eigrpd.conf} is not there next
search current directory.  If an integrated config is specified
configuration is written into frr.conf

The EIGRP protocol requires interface information
maintained by @command{zebra} daemon.  So running @command{zebra}
is mandatory to run @command{eigrpd}.  Thus minimum sequence for running
EIGRP is like below:

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

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

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

@table @samp
@item SIGHUP
@item SIGUSR1
Rotate @command{eigrpd} Rotate the logfile.
@item SIGINT
@itemx SIGTERM
@command{eigrpd} sweeps all installed EIGRP routes then terminates properly.
@end table

@command{eigrpd} 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{eigrpd}.
@end table

@node EIGRP Configuration
@section EIGRP Configuration

@deffn Command {router eigrp (1-65535)} {}
The @code{router eigrp} command is necessary to enable EIGRP.  To disable
EIGRP, use the @code{no router eigrp (1-65535)} command.  EIGRP must be enabled before carrying out any of the EIGRP commands.
@end deffn

@deffn Command {no router eigrp (1-65535)} {}
Disable EIGRP.
@end deffn

@deffn {EIGRP Command} {network @var{network}} {}
@deffnx {EIGRP Command} {no network @var{network}} {}
Set the EIGRP enable interface by @var{network}.  The interfaces which
have addresses matching with @var{network} are enabled.

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

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

@example
@group
!
router eigrp 1
 network 10.0.0.0/8
!
@end group
@end example

Passive interface

@deffn {EIGRP command} {passive-interface (@var{IFNAME}|default)} {}
@deffnx {EIGRP command} {no passive-interface @var{IFNAME}} {}
This command sets the specified interface to passive mode.  On passive mode
interface, all receiving packets are ignored and eigrpd does
not send either multicast or unicast EIGRP packets except to EIGRP neighbors
specified with @code{neighbor} command. The interface may be specified
as @var{default} to make eigrpd default to passive on all interfaces. 

The default is to be passive on all interfaces.
@end deffn

@node How to Announce EIGRP route
@section How to Announce EIGRP route

@deffn {EIGRP command} {redistribute kernel} {}
@deffnx {EIGRP command} {redistribute kernel metric (1-4294967295) (0-4294967295) (0-255) (1-255) (1-65535)} {}
@deffnx {EIGRP command} {no redistribute kernel} {}
@code{redistribute kernel} redistributes routing information from
kernel route entries into the EIGRP tables. @code{no redistribute kernel}
disables the routes.
@end deffn

@deffn {EIGRP command} {redistribute static} {}
@deffnx {EIGRP command} {redistribute static metric (1-4294967295) (0-4294967295) (0-255) (1-255) (1-65535)} {}
@deffnx {EIGRP command} {no redistribute static} {}
@code{redistribute static} redistributes routing information from
static route entries into the EIGRP tables. @code{no redistribute static}
disables the routes.
@end deffn

@deffn {EIGRP command} {redistribute connected} {}
@deffnx {EIGRP command} {redistribute connected metric (1-4294967295) (0-4294967295) (0-255) (1-255) (1-65535)} {}
@deffnx {EIGRP command} {no redistribute connected} {}
Redistribute connected routes into the EIGRP tables.  @code{no
redistribute connected} disables the connected routes in the EIGRP tables.
This command redistribute connected of the interface which EIGRP disabled.
The connected route on EIGRP enabled interface is announced by default.
@end deffn

@deffn {EIGRP command} {redistribute ospf} {}
@deffnx {EIGRP command} {redistribute ospf metric (1-4294967295) (0-4294967295) (0-255) (1-255) (1-65535)} {}
@deffnx {EIGRP command} {no redistribute ospf} {}
@code{redistribute ospf} redistributes routing information from
ospf route entries into the EIGRP tables. @code{no redistribute ospf}
disables the routes.
@end deffn

@deffn {EIGRP command} {redistribute bgp} {}
@deffnx {EIGRP command} {redistribute bgp metric  (1-4294967295) (0-4294967295) (0-255) (1-255) (1-65535)} {}
@deffnx {EIGRP command} {no redistribute bgp} {}
@code{redistribute bgp} redistributes routing information from
bgp route entries into the EIGRP tables. @code{no redistribute bgp}
disables the routes.
@end deffn

@node Show EIGRP Information
@section Show EIGRP Information

To display EIGRP routes.

@deffn Command {show ip eigrp topology} {}
Show EIGRP routes.
@end deffn

The command displays all EIGRP routes.

@c Exmaple here.

@deffn Command {show ip eigrp topology} {}
The command displays current EIGRP status
@end deffn

@example
@group
eigrpd> @b{show ip eigrp topology}
# show ip eigrp topo

EIGRP Topology Table for AS(4)/ID(0.0.0.0)

Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply
       r - reply Status, s - sia Status

P  10.0.2.0/24, 1 successors, FD is 256256, serno: 0 
       via Connected, enp0s3
@end group
@end example

@node EIGRP Debug Commands
@section EIGRP Debug Commands

Debug for EIGRP protocol.

@deffn Command {debug eigrp packets} {}
Debug eigrp packets
@end deffn

@code{debug eigrp} will show EIGRP packets that are sent and recevied.

@deffn Command {debug eigrp transmit} {}
Debug eigrp transmit events
@end deffn

@code{debug eigrp transmit} will display detailed information about the EIGRP transmit events.

@deffn Command {show debugging eigrp} {}
Display @command{eigrpd}'s debugging option.
@end deffn

@code{show debugging eigrp} will show all information currently set for eigrpd
debug.
