IP Routing Features

Configuring RIP

Changing the Route Loop Prevention Method

RIP can use the following methods to prevent routing loops:

Split horizon - the routing switch does not advertise a route on the same interface as the one on which the routing switch learned the route.

Poison reverse - the routing switch assigns a cost of 16 (“infinity” or “unreachable”) to a route before advertising it on the same interface as the one on which the routing switch learned the route. This is the default.

 

These loop prevention methods are configurable on an individual VLAN

 

interface basis.

 

 

N o t e

These methods are in addition to RIP's maximum valid route cost of 15.

 

Poison reverse is enabled by default. Disabling poison reverse causes the

 

 

routing switch to revert to Split horizon. (Poison reverse is an extension of

 

Split horizon.) To disable Poison reverse on an interface, and thereby enable

 

Split horizon, enter the following:

 

HPswitch(config)# vlan 1

 

HPswitch(vlan-1)# no ip rip poison-reverse

 

Syntax: [no] ip rip poison-reverse

 

Entering the command without the “no” option will re-enable Poison reverse.

Displaying RIP Information

All RIP configuration and status information is shown by the CLI command show ip rip and options off that command. The following RIP information can be displayed:

RIP Information Type

Page

 

 

General Information

16-27

Interface Information

16-29

Peer Information

16-30

Redistribute Information

16-32

Restrict Information

16-32

 

 

16-26