Brocade BigIron RX Series Configuration Guide - Manual (Page 826)

748 BigIron RX Series Configuration Guide
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Configuring RIP parameters
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• Poison reverse – The device assigns a cost of 16 (“infinite” or “unreachable”) to a route before
advertising it on the same interface as the one on which the router learned the route. This is
the default.
These loop prevention methods are configurable on a global basis as well as on an individual
interface basis. One of the methods is always in effect on an interface enabled for RIP. Thus, if you
disable one method, the other method is enabled.
NOTE
These methods are in addition to RIP’s maximum valid route cost of 15.
To disable poison reverse and enable split horizon on a global basis, enter the following command.
BigIron RX(config-rip-router)# no poison-reverse
Syntax: [no] poison-reverse
To disable poison reverse and enable split horizon on an interface, enter commands such as the
following.
BigIron RX(config)# router rip
BigIron RX(config)# interface ethernet 1/1
BigIron RX(config-if-e10000-1/1)# no ip rip poison-reverse
Syntax: [no] ip rip poison-reverse
To disable split horizon and enable poison reverse on an interface, enter the command such as the
following.
BigIron RX(config)# router rip
BigIron RX(config)# interface ethernet 1/1
BigIron RX(config-if-e10000-1/1)# ip rip poison-reverse
You can configure the device to avoid routing loops by advertising local RIP routes with a cost of 16
(“infinite” or “unreachable”) when these routes go down.
BigIron RX(config-rip-router)# poison-local-routes
Syntax: [no] poison-local-routes
Suppressing RIP route advertisement on a VRRP or VRRPE
backup interface
NOTE
This section applies only if you configure the device for Virtual Router Redundancy Protocol (VRRP)
or VRRP Extended (VRRPE). Refer to
Chapter 17, “Configuring VRRP and VRRPE” .
Normally, a VRRP or VRRPE Backup includes route information for the virtual IP address (the
backed up interface) in RIP advertisements. As a result, other routers receive multiple paths for the
backed up interface and might sometimes unsuccessfully use the path to the Backup rather than
the path to the Master.
You can prevent the Backups from advertising route information for the backed up interface by
enabling suppression of the advertisements.
To suppress RIP advertisements for the backed up interface in Router2, enter the following
commands.