Example: Redistributing Static Routes to IS-IS Using a Route Map and an Access List

This example explains how to use a route map and an access list to redistribute static routes to IS-IS.

Requirements

This example uses the following software and hardware components:

Overview

Route maps are used to control and modify routing information and to define conditions for redistributing routes between routing domains. You can apply route maps to inbound, outbound, or redistribution routes. An access list is a sequential collection of permit and deny conditions that you can use to filter inbound or outbound routes.

Configuration

Step-by-Step Procedure

The following example demonstrates about how to use a route map and an access list to redistribute static routes to IS-IS.

To use a route map and an access list to redistribute static routes to IS-IS:

  1. Configure three static routes.
    host1(config)#ip route 20.20.20.0 255.255.255.0 192.168.1.0 host1(config)#ip route 20.20.21.0 255.255.255.0 192.168.2.0 host1(config)#ip route 20.21.0.0 255.255.255.0 192.168.30.0
  2. Configure an access list, fltra, that filters routes 20.20.20.0/24 and 20.20.21.0/24.
    host1(config)#access-list fltra permit 20.20.0.0 0.0.255.255
  3. Configure route map 1 to match access list fltra, and apply an internal metric type.
    host1(config)#route-map 1 host1(config-route-map)#match ip address fltra host1(config-route-map)#set metric-type internal
  4. Configure redistribution into IS-IS of the static routes with route map 1.
    host1(config)#router isis testnet host1(config-router)#redistribute static route-map 1

Verification

To confirm that the configuration is working properly, perform this task:

Monitoring the Database Details

Purpose

Displays the IS-IS database detail to verify the effect of the redistribution (the two static routes matching the route map are redistributed as level 2 internal routes).

Action

To display the IS-IS database detail:

host1#show isis database detail l2
IS-IS Level-2 Link State Database
LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/OL 
0000.0000.6666.00-00 0x000002B7   0x3E1F 1198 0/0/0
  Area Address: 47.0005.80FF.F800.0000.0001.0001
  NLPID:       0xcc
  IP Address:  192.168.1.105
  Metric: 10 IS 0000.0000.6666.01
  Metric: 10 IS 0000.0000.3333.00
  Metric: 10 IS 0000.0000.7777.00 
Metric: 30 IP 20.20.20.0 255.255.255.0
Metric: 30 IP 20.20.21.0 255.255.255.0

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