This document describes how to create an Intermediate System-to-Intermediate System (IS-IS) topology from a CLI output of a router with IOS-XR software installed.
Contributed by Agung Semarajaya, Cisco TAC Engineer.
Cisco recommends that you have sound knowledge of these topics:
The information in this document is based on these software and hardware versions:
ASR 9001 with IOS-XR version 6.3.2
Lenovo P50 with 64-bit Windows 10 Enterprise OS
Graphviz release 2.38
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, ensure that you understand the potential impact of any command.
In order to troubleshoot an IS-IS network, it is important to understand how the routers are interconnected for various reasons. You can have the topology information, however, the topology is outdated.
From IOS-XR version 6.3.2, the show isis database graph verbose command is introduced to produce a network topology graph in DOT format which can use as an input to rendering tools.
Ensure that you have IS-IS adjacencies built and at least one router with IOS-XR version 6.3.2 or above installed. Use these steps to create the updated IS-IS topology from the CLI output.
Step 1. Run the command show isis database graph verbose on the IOS-XR device.
Step 2. Copy the content of the command from step 1 to a text file and save the file in .txt format.
Note: In step 5 you can simply set the path variable to the directory where the Graphviz CLI executable files are located.
1. If you run level 1 and level 2 in IS-IS and both are present, then only level 1 appears in the show isis database graph verbose output (the first digraph). To fix this issue, you can edit the input file and remove the digraph for level 1 or level 2, or you can take the input and use these commands with the level 1 or level 2 keyword.
show isis database graph level 1 verbose
show isis database graph level 2 verbose
2. DOT tends to crash when the file contains [label=0] elements. One approach is to simply edit these out and then execute the CLI.
Note: Other tools, such as Circo, does not have this issue.