670 BigIron RX Series Configuration Guide53-1001810-01Configuring RIP parameters24These loop prevention methods are configurable on a global basis as well as on an individualinterface basis. One of the methods is always in effect on an interface enabled for RIP. Thus, if youdisable one method, the other method is enabled.NOTEThese 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-reverseSyntax: [no] poison-reverseTo disable poison reverse and enable split horizon on an interface, enter commands such as thefollowing.BigIron RX(config-if-e10000-1/1)# no ip rip poison-reverseSyntax: [no] ip rip poison-reverseTo disable split horizon and enable poison reverse on an interface, enter the command such as thefollowing.BigIron RX(config-if-e10000-1/1)# ip rip poison-reverseYou 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-routesSyntax: [no] poison-local-routesSuppressing RIP route advertisement on a VRRP or VRRPE backupinterfaceNOTEThis section applies only if you configure the BigIron RX 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 (thebacked up interface) in RIP advertisements. As a result, other routers receive multiple paths forthe backed up interface and might sometimes unsuccessfully use the path to the Backup ratherthan the path to the Master.You can prevent the Backups from advertising route information for the backed up interface byenabling suppression of the advertisements.To suppress RIP advertisements for the backed up interface in Router2, enter the followingcommands.Router2(config)# router ripRouter2(config-rip-router)# use-vrrp-pathSyntax: [no] use-vrrp-pathThe syntax is the same for VRRP and VRRPE.
