Changing the administrative distance, Configuring redistribution, Configuring redistribution filters – Brocade BigIron RX Series Configuration Guide User Manual

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BigIron RX Series Configuration Guide

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Configuring RIP parameters

25

Changing the administrative distance

By default, the device assigns the default RIP administrative distance (120) to RIP routes. When
comparing routes based on administrative distance, the device selects the route with the lower
distance. You can change the administrative distance for RIP routes.

NOTE

Refer to

“Changing administrative distances”

on page 842 for a list of the default distances for all

route sources.

To change the administrative distance for RIP routes, enter a command such as the following.

BigIron RX(config-rip-router)# distance 140

The command changes the administrative distance to 140 for all RIP routes.

Syntax: [no] distance <number>

The number is 1 - 255.

Configuring redistribution

You can configure the device to redistribute routes learned through OSPF or BGP4, connected into
RIP, or static routes. When you redistribute a route from one of these other protocols into RIP, the
device can use RIP to advertise the route to its RIP neighbors.

To configure redistribution, perform the following tasks:

Configure redistribution filters. You can configure filters to permit or deny redistribution for a
route based on its origin (OSPF, BGP4, and so on), the destination network address, and the
route’s metric. You also can configure a filter to set the metric based on these criteria.

Change the default redistribution metric (optional). The device assigns a RIP metric of one to
each redistributed route by default. You can change the default metric to a value up to 16.

Configuring redistribution filters

RIP redistribution filters apply to all interfaces. You use route maps to define how you want to deny
or permit redistribution.

NOTE

The default redistribution action is permit, even after you configure and apply redistribution filters
to the virtual routing interface. If you want to tightly control redistribution, apply a filter to deny all
routes as the last filter (the filter with the highest ID), then apply filters to allow specific routes.

A route map is a named set of match conditions and parameter settings that the router can use to
modify route attributes and to control redistribution of the routes into other protocols. A route map
consists of a sequence of up to 50 instances. If you think of a route map as a table, an instance is
a row in that table. The router evaluates a route according to a route map’s instances in ascending
numerical order. The route is first compared against instance 1, then against instance 2, and so
on. As soon as a match is found, the router stops evaluating the route against the route map
instances.

Route maps can contain match statements and set statements. Each route map contains a
“permit” or “deny” action for routes that match the match statements.

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