Cisco Systems IOS XR How to Implement Static Routes on Cisco IOS XR Software

Implementing Static Routes on Cisco IOS XR Software

How to Implement Static Routes on CiscoIOS XR Software

RC-250

Cisco IOS XR Routing Configuration Guide

In a fully specified static route, both the output interface and next hop are specifi ed. This form of static

route is used when the output interface is a multiaccess one and it is necessary to explicitly identify the

next hop. The next hop must be directly attached to the spec ified output interface. The following

example shows a definition of a fully specified static route:

RP/0/RP0/CPU0:router(config)# route ipv6 unicast 2001:0DB8::/32 2001:0DB8:3000::1

A fully specified route is valid (that is, a candidate for insertion into the routing table) when the specified

interface is IPv4 or IPv6 enabled and up.

Floating static routes are static routes that are used to back up dynamic routes lea rned through configured

routing protocols. A floating static route is configured with a higher administrative distance than the

dynamic routing protocol it is backing up. As a res ult, the dynamic route learned through the routing

protocol is always preferred to the floating static route. If the dynamic r oute learned through the routing

protocol is lost, the floating static route is used in its pl ace. The following example shows how to define

a floating static route:

RP/0/RP0/CPU0:router(config)# route ipv6 unicast 2001:0DB8::/32 2001:0DB8:3000::1 210

Any of the three types of static routes can be used as a floating static route. A fl oating static route must

be configured with an administrative distance that is greater than the administrative distance of the

dynamic routing protocol because routes with smaller administrative distances are preferred.

Note By default, static routes have smaller administrative distances than dynamic routes, so static routes

preferred to dynamic routes.

How to Implement Static Routes on Cisco IOS XR Software

This section contains the following procedures:

•Configuring a Static Route, page RC-250 (required)

•Configuring a Floating Static Route, page RC-251 (optional)

•Changing the Maximum Number of Allowable Static Routes, page RC-253 ( optional)

This task explains how to configure a static route.

SUMMARY STEPS

1. configure

2. route {ipv4 | ipv6} {unicast | multicast} prefix mask {ip-address | interface-type

interface-instance} [distance] [tag tag] [permanent]