Implementing IS-IS on Cisco IOS XR Software

How to Implement IS-IS on Cisco IOS XR Software

 

Command or Action

Purpose

Step 5

 

 

default-information originate [route-map

(Optional) Injects a default IPv4 or IPv6 route into an IS-IS

 

map-name]

routing domain.

 

Example:

The route-mapkeyword and map-nameargument

 

specify the conditions under which the IPv4 or IPv6

 

RP/0/RP0/CPU0:router(config-isis-af)#

default route is advertised.

 

default-information originate

If the route-mapkeyword is omitted, then the IPv4 or

 

 

 

 

IPv6 default route is unconditionally advertised at

 

 

Level 2.

Step 6

 

 

redistribute isis instance [level-1 level-2

(Optional) Redistributes routes from one IS-IS instance into

 

level-1-2] [metric metric] [metric-type

another instance.

 

{internal external}] [policy policy-name]

In this example, an IS-IS instance redistributes IS-IS

 

 

 

Example:

instance 2 routes into its Level 1 area.

 

 

 

RP/0/RP0/CPU0:router(config-isis-af)#

 

 

redistribute isis 2 level-1

 

Step 7

 

 

summary-prefix [address/prefix-length] [level

(Optional) Allows a Level 1-2 router to summarize Level 1

 

{1 2}]

IPv4 and IPv6 prefixes at Level 2, instead of advertising the

 

or

Level 1 prefixes directly when the router advertises the

 

 

 

summary-prefix[ipv6-prefix/prefix-length]

summary.

 

[level {1 2}]

This example specifies an IPv4 address and mask.

 

 

 

Example:

or

 

This example specifies an IPv6 prefix, and the

 

RP/0/RP0/CPU0:router(config-isis-af)#

 

summary-prefix 10.1.0.0/16 level 1

command must be in the form documented in RFC 2373

 

or

in which the address is specified in hexadecimal using

 

RP/0/RP0/CPU0:router(config-isis-af)#

16-bit values between colons.

 

summary-prefix 3003:xxxx::/24 level 1

Note that IPv6 prefixes must be configured only in the

 

 

 

 

IPv6 router address family configuration submode, and

 

 

IPv4 prefixes in the IPv4 router address family

 

 

configuration submode.

Step 8

 

 

maximum-paths route-number

(Optional) Configures the maximum number of parallel

 

 

paths allowed in a routing table.

 

Example:

 

 

RP/0/RP0/CPU0:router(config-isis-af)#

 

 

maximum-paths 16

 

 

 

 

Step 9

distance weight [address/prefix-length

(Optional) Defines the administrative distance assigned to

 

[route-list-name]]

routes discovered by the IS-IS protocol.

 

Example:

A different administrative distance may be applied for

 

IPv4 and IPv6.

 

RP/0/RP0/CPU0:router(config-isis-af)# distance

 

 

90

 

 

 

 

Cisco IOS XR Routing Configuration Guide

RC-121

Page 137
Image 137
Cisco Systems IOS XR manual Instance 2 routes into its Level 1 area, RC-121

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.