User's Manual

IPC-521
Cisco IOS IP Configuration Guide
Using IP Multicast Tools
This chapter describes IP multicast tools that allow you to trace a multicast path or test a multicast
environment. For a complete description of the commands in this chapter, refer to the “IP Multicast Tools
Commands” chapter in the Cisco IOS IP Command Reference, Volume 3 of 3: Multicast publication. To
locate documentation of other commands that appear in this chapter, use the command reference master
index, or search online.
To identify the hardware platform or software image information associated with a feature, use the
Feature Navigator on Cisco.com to search for information about the feature or refer to the software
release notes for a specific release. For more information, see the “Identifying Supported Platforms”
section in the “Using Cisco IOS Software” chapter.
Multicast Routing Monitor Overview
The Multicast Routing Monitor (MRM) feature is a management diagnostic tool that provides network
fault detection and isolation in a large multicast routing infrastructure. It is designed to notify a network
administrator of multicast routing problems in near real time.
MRM has three components that play different roles: the Manager, the Test Sender, and the Test
Receiver. To test a multicast environment using test packets, perhaps before an upcoming multicast
event, you need all three components.
You create a test based on various test parameters, name the test, and start the test. The test runs in the
background and the command prompt returns.
If the Test Receiver detects an error (such as packet loss or duplicate packets), it sends an error report to
the router configured as the Manager. The Manager immediately displays the error report. (Also, by
issuing a certain show EXEC command, you can see the error reports, if any.) You then troubleshoot
your multicast environment as normal, perhaps using the mtrace command from the source to the Test
Receiver. If the show EXEC command displays no error reports, the Test Receiver is receiving test
packets without loss or duplicates from the Test Sender.
The Cisco implementation of MRM supports Internet Draft of Multicast Routing Monitor (MRM),
Internet Engineering Task Force (IETF), March 1999.
Benefits
The benefits of the MRM feature are as follows:
• Find fault in multicast routing in near real time—If a problem exists in the multicast routing
environment, you will find out about it right away.