Implementing IS-IS on Cisco IOS XR Software

How to Implement IS-IS on Cisco IOS XR Software

DETAILED STEPS

 

Command or Action

Purpose

Step 1

 

 

configure

Enters global configuration mode.

 

Example:

 

 

RP/0/RP0/CPU0:router# configure

 

Step 2

 

 

router isis instance-id

Enables IS-IS routing for the specified routing instance, and

 

 

places the router in router configuration mode.

 

Example:

You can change the level of routing to be performed by

 

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

a particular routing instance using the is-typerouter

 

 

configuration command.

Step 3

 

 

address-family {ipv4 ipv6} [unicast]

Specifies the IPv4 or IPv6 address family, and enters router

 

 

address family configuration mode.

 

Example:

This example specifies the unicast IPv6 address family.

 

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

 

 

address-family ipv6 unicast

 

Step 4

 

 

spf-interval {[initial-wait initial

(Optional) Controls the minimum time between successive

 

secondary-wait secondary maximum-wait

SPF calculations.

 

maximum] ...} [level {1 2}]

This value imposes a delay in the SPF computation

 

 

 

Example:

after an event trigger and enforces a minimum elapsed

 

time between SPF runs.

 

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

 

If this value is configured too low, the router can lose

 

spf-interval initial-wait 10 maximum-wait 30

 

 

too many CPU resources when the network is unstable.

 

 

Configuring the value too high delays changes in the

 

 

network topology that result in lost packets.

 

 

The SPF interval does not apply to the running of the

 

 

ISPF because that algorithm runs immediately on

 

 

receiving a changed LSP.

Step 5

 

 

ispf [startup-delay seconds] [level {1 2}]

(Optional) Configures incremental IS-IS ISPF to calculate

 

 

network topology.

 

Example:

 

 

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

 

Step 6

 

 

ispf startup-delay seconds [level {1 2}]

(Optional) Configures the time delay between the starting

 

 

of the IS-IS instance and the activation of ISPF.

 

Example:

 

 

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

 

 

startup-delay 600

 

 

 

 

Cisco IOS XR Routing Configuration Guide

RC-117

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Cisco Systems IOS XR manual RC-117

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.