RIPng Configuration Overview

To configure RIPng, you must enable RIPng globally on the device and on individual device interfaces.

The following RIPng configuration tasks are optional:

  • Change the default settings of RIPng timers
  • Configure poison reverse parameters
  • Configure how the device learns and advertises routes
  • Configure which routes are redistributed into RIPng from other sources
  • Configure how the device distributes routes through RIPng

RIPng Timers

You can adjust timers for RIPng. Before doing so, keep the following caveats in mind:

  • If you adjust RIPng timers, RUCKUS strongly recommends setting the same timer values for all routers and access servers in the network.
  • Setting the update timer to a shorter interval can cause the devices to spend excessive time updating the IPv6 route table.
  • RUCKUS recommends setting the timeout timer value to at least three times the value of the update timer.
  • RUCKUS recommends a shorter hold-down timer interval because a longer interval can cause delays in RIPng convergence.

RIPng Route Loop Prevention

By default, split horizon is enabled as the route loop prevention method. Split horizon prevents advertising a route on the same interface over which the route is learned. If poison reverse is enabled, RIPng advertises routes it learns from a particular interface over that same interface with a metric of 16, which means that the route is unreachable. Enabling poison reverse on the RIPng device disables split-horizon and vice versa.

By default, if a RIPng interface goes down, the device does not send a triggered update for the interface’s IPv6 networks. You can use the poison-local-routes command to configure a RIPng device to send a triggered update containing the local routes of the disabled interface with an unreachable metric of 16 to the other RIPng routers in the routing domain.

RIPng Route Learning and Advertisement

You can configure the following learning and advertising parameters:

  • Learning and advertising of RIPng default routes: By default, the device does not learn IPv6 default routes (::/0). You can originate default routes into RIPng, which causes individual device interfaces to include the default routes in their updates. When configuring the origination of the default routes, you can include only the default routes, or you can include default routes and all other routes.
  • Advertising of IPv6 address summaries: You can configure RIPng to advertise a summary of IPv6 addresses from a device interface and to specify an IPv6 prefix that summarizes the routes instead of advertising the original route. If a route’s prefix length matches the value specified in the ipv6 rip summary-address command, RIPng advertises the prefix specified in the command instead of the original route.
  • Metric of routes learned and advertised on a device interface: You can change the metric offset an individual interface adds to a route it learns or advertises.

Route Redistribution into RIPng

You can configure the device to redistribute routes from the following sources into RIPng:

  • IPv6 static routes
  • Directly connected IPv6 networks
  • BGP4+
  • OSPFv3

When you redistribute a route from BGP4+ or OSPFv3 into RIPng, the device can use RIPng to advertise the route to its RIPng neighbors.

When configuring the device to redistribute routes, such as BGP4+ routes, you can optionally specify a metric for the redistributed routes. If you do not explicitly configure a metric, the default metric value of one is used.

Applying Filters to RIPng Route Redistribution

You can create a prefix list and then apply it to RIPng routing updates that are received or sent on a device interface. Performing this task allows you to control the distribution of routes through RIPng.

For example, to create and apply a prefix list that permits only routes with the prefix 2001:db8::/32 in RIPng routing updates sent to RIPng neighbor routers, enter the following commands. 

device(config)# ipv6 prefix-list routesfor2001 permit 2001:db8::/32
device(config)# ipv6 router rip
device(config-ripng-router)# distribute-list prefix-list routesfor2001 out

To create and apply a prefix list to deny prefix lengths greater than 64 bits in routes that have the prefix 2001:db8::/64 and allow all other routes received from RIPng neighbor routers, enter the following commands. 

device(config)# ipv6 prefix-list 2001routes deny 2001:db8::/64 le 128
device(config)# ipv6 prefix-list 2001routes permit ::/0 ge 0 le 128
device(config)# ipv6 router rip
device(config-ripng-router)# distribute-list prefix-list 2001routes in
Parent topic: RIPng