Implementing Routing Policy on Cisco IOS XR Software

Configuration Examples for Implementing Routing Policy

DETAILED STEPS

 

Command or Action

Purpose

Step 1

 

 

edit {route-policy prefix-set as-path-set

Identifies the route policy, prefix set, AS path set,

 

community-set extended-community-set}name

community set, or extended community set name to be

 

 

modified.

 

Example:

• A copy of the route policy, prefix set, AS path set,

 

RP/0/RP0/CPU0:router# edit route-policy sample1

community set, or extended community set is copied to

 

 

a temporary file and the microemacs editor is launched.

 

 

When you finish editing the policy or set, save the

 

 

changes by using the save-buffercommand, ^X^S

 

 

(Control-X Control-S).

 

 

To commit the changed configuration:

 

 

• save the buffer (Control-X Control-S)

 

 

• exit MicroEmacs (Control-X Control-C)

Step 2

 

 

show rpl route-policy name [detail]

(Optional) Displays the configuration of a specific named

 

 

route policy.

 

Example:

• Use the detail keyword to display all policies and sets

 

RP/0/RP0/CPU0:router# show rpl route-policy

that a policy uses.

 

sample2

 

Step 3

 

 

show rpl prefix-set name

(Optional) Displays the contents of a named prefix set.

 

 

• To display the contents of a named AS path set,

 

Example:

community set, or extended community set, replace the

 

RP/0/RP0/CPU0:router# show rpl prefix-set

prefix-set keyword with as-path-set,community-set,

 

prefixset1

or extcommunity-set, respectively.

 

 

 

Configuration Examples for Implementing Routing Policy

This section provides the following configuration examples:

•Routing Policy Definition: Example, page RC-241

•Simple Inbound Policy: Example, page RC-242

•Modular Inbound Policy: Example, page RC-243

•Translating Cisco IOS Route Maps to Cisco IOS XR Routing Policy Language: Example, page RC-244

Routing Policy Definition: Example

In the following example, a BGP route policy named sample1 is defined using the route-policyname command. The policy compares the network layer reachability information (NLRI) to the elements in the prefix set test. If it evaluates to true, the policy performs the operations in the then clause. If it evaluates to false, the policy performs the operations in the else clause, that is, sets the MED value to 200 and adds the community 2:100 to the route. The final steps of the example commit the configuration to the router, exit configuration mode, and display the contents of route policy sample1.

Cisco IOS XR Routing Configuration Guide

RC-241

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Cisco Systems IOS XR manual Routing Policy Definition Example, RC-241
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IOS XR specifications

Cisco Systems IOS XR is an advanced operating system designed specifically for high-performance routers and service provider networks. It serves as the backbone for many of Cisco's high-end routing platforms, enabling service providers to manage their networks with increased efficiency, flexibility, and scalability.

One of the main features of IOS XR is its modular architecture. This allows for the independent operation of various components within the OS, facilitating the deployment of new features and updates without affecting the overall stability of the system. This modularity ensures that service providers can implement rapid changes and enhancements while maintaining service continuity.

Another characteristic of IOS XR is its support for 64-bit architecture, which provides enhanced performance and the ability to manage larger amounts of data. This is particularly beneficial for service providers that deal with high traffic volumes and require robust data processing capabilities. The utilization of 64-bit technology also enables the operating system to utilize memory more efficiently, allowing for greater scalability.

IOS XR incorporates advanced technologies such as Distributed System Architecture (DSA) and Multiple Routing Instances (Merging Routes). DSA allows for the distribution of routing processes across multiple hardware resources, maximizing performance and redundancy. Multiple Routing Instances enable operators to create separate logical routing tables for different services, improving isolation and efficiency in managing network traffic.

The operating system also focuses heavily on security, featuring extensive encryption methods and access controls to safeguard network resources. IOS XR supports various authentication protocols, ensuring secure access to routers and switches. In addition, the OS includes comprehensive logging and monitoring capabilities, allowing network administrators to track activities and respond quickly to potential threats.

Another critical aspect of IOS XR is its adherence to the principles of service-oriented architecture (SOA). This approach permits the development of applications and services that can operate independently, fostering innovation and enabling service providers to tailor their offerings based on customer demands.

Ultimately, Cisco IOS XR is a powerful, reliable operating system that meets the complex needs of modern telecommunications networks. With its focus on modularity, performance, security, and scalability, it enables service providers to deliver high-quality, resilient services to their customers while efficiently managing network resources. As the industry continues to evolve, IOS XR remains a vital tool for those aiming to stay competitive in the ever-changing landscape of networking.
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