Using the Multicast Routing Monitor

The Multicast Routing Monitor (MRM) 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 a test environment.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Restrictions for Using the Multicast Routing Monitor

You must make sure the underlying multicast forwarding network being tested has no access lists or boundaries that deny the MRM data and control traffic. Specifically, consider the following factors:

  • MRM test data are User Datagram Protocol (UDP) and Real-Time Transport Protocol (RTP) packets addressed to the configured multicast group address.

  • MRM control traffic between the Test Sender, Test Receiver, and Manager is addressed to the 224.0.1.111 multicast group, which all three components join. The 224.0.1.111 group is an IANA-registered group.

  • Take into account the unicast IP addresses of sources and receivers when considering what could prevent control traffic flowing.

Information About the Multicast Routing Monitor

Multicast Routing Monitor Operation

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 device configured as the Manager. The Manager immediately displays the error report. (The show ip mrm status-reportcommand also displays 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 ip mrm status-reportcommand 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. The IETF originally conceived MRM to use both test packets and real data. The Cisco implementation does not use real data due to technical issues and the fact that the IETF draft did not progress.

Benefits of Multicast Routing Monitor

The benefits of the MRM are as follows:

  • MRM allows network personnel to generate test flows without having to use host devices.

  • MRM can verify a multicast environment prior to an event. You need not wait for real multicast traffic to fail in order to find out that a problem exists. You can test the multicast routing environment before a planned event.

  • MRM provides easy diagnostics. The error information is easy for the user to understand.

  • MRM is scalable. This diagnostic tool works well for many users.

How to Use the Multicast Routing Monitor

Configuring a Test Receiver

Perform this task to configure a Test Receiver on a device or host.

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    interface type number

    4.    ip mrm test-receiver

    5.    exit

    6.    ip mrm accept-manager access-list


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Device> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.

     
    Step 2 configure terminal


    Example:
    Device# configure terminal
     

    Enters global configuration mode.

     
    Step 3 interface type number


    Example:
    Device(config)# interface gigabitethernet 0/0/0
     

    Specifies an interface, and enters interface configuration mode.

     
    Step 4 ip mrm test-receiver


    Example:
    Device(config-if)# ip mrm test-receiver
     

    Configures the interface to operate as a Test Receiver.

     
    Step 5 exit


    Example:
    Device(config-if)# exit
     

    Returns to the next higher configuration mode.

     
    Step 6 ip mrm accept-manager access-list


    Example:
    Device(config)# ip mrm accept-manager supervisor
     

    (Optional) Specifies that the Test Receiver can accept status report requests only from Managers specified by the access list.

    • The access list is required and can be named or numbered.

    • This example uses an access list named “supervisor.” The access list is presumed to be already configured.

     

    Configuring a Test Sender

    Perform this task to configure a Test Sender on a different device or host from where you configured the Test Receiver.

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    interface type number

      4.    ip mrm test-sender

      5.    exit

      6.    ip mrm accept-manager [access-list]


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Device> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.

       
      Step 2 configure terminal


      Example:
      Device# configure terminal
       

      Enters global configuration mode.

       
      Step 3 interface type number


      Example:
      Device(config)# interface gigiabitethernet 0/0/0
       

      Specifies an interface, and enters interface configuration mode.

       
      Step 4 ip mrm test-sender


      Example:
      Device(config-if)# ip mrm test-sender
       

      Configures the interface to operate as a Test Sender.

       
      Step 5 exit


      Example:
      Device(config-if)# exit
       

      Returns to the next higher configuration mode.

       
      Step 6 ip mrm accept-manager [access-list]


      Example:
      Device(config)# ip mrm accept-manager supervisor
       

      (Optional) Specifies that the Test Sender can accept status report requests only from Managers specified by the access list.

      • This example uses an access list named “supervisor.” The access list is presumed to be already configured.

       

      Monitoring Multiple Groups

      If you have more than one multicast group to monitor, you can configure an interface that is a Test Sender for one group and a Test Receiver for another group.

      The figure illustrates an environment where the router on the left is the Test Sender for Group A and the Test Receiver for Group B.

      Figure 1. Test Sender and Test Receiver for Different Groups on One Router

      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    interface type number

        4.    ip mrm test-sender-receiver

        5.    exit

        6.    ip mrm accept-manager access-list [test-sender | test-receiver]


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example:
        Router> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.

         
        Step 2 configure terminal


        Example:
        Router# configure terminal
         

        Enters global configuration mode.

         
        Step 3 interface type number


        Example:
        Router(config)# interface gigabitethernet 0/0/0
         

        Specifies an interface, and enters interface configuration mode.

         
        Step 4 ip mrm test-sender-receiver


        Example:
        Router(config-if)# ip mrm test-sender-receiver
         

        Configures the interface to operate as a Test Sender for one group and Test Receiver for another group.

         
        Step 5 exit


        Example:
        Router(config-if)# exit
         

        Returns to the next higher configuration mode.

         
        Step 6 ip mrm accept-manager access-list [test-sender | test-receiver]


        Example:
        Router(config)# ip mrm accept-manager supervisor test-sender
         

        (Optional) Specifies that the Test Sender or Test Receiver can accept status report requests only from Managers specified by the access list.

        • By default, the command applies to both the Test Sender and Test Receiver. Because this device is both, you might need to specify that the restriction applies to only the Test Sender or only the Test Receiver using the test-sender keyword or test-receiver keyword, respectively.

         

        Configuring a Manager

        Perform this task to configure a device as a Manager in order for MRM to function.


        Note

        A host cannot be a Manager.

        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    ip mrm manager test-name

          4.    manager type number group ip-address

          5.    beacon [interval seconds] [holdtime seconds][ttl ttl-value]

          6.    udp-port test-packet port-number ] status-report port-number ]

          7.    senders access-list [packet-delay milliseconds] [rtp| udp] [target-only| all-multicasts| all-test-senders]

          8.    receivers access-list sender-list access-list [packet-delay]

          9.    receivers access-list [window seconds] [report-delay seconds] [loss percentage] [no-join] [monitor | poll]


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 enable


          Example:
          Device> enable
           

          Enables privileged EXEC mode.

          • Enter your password if prompted.

           
          Step 2 configure terminal


          Example:
          Device# configure terminal
           

          Enters global configuration mode.

           
          Step 3 ip mrm manager test-name


          Example:
          Device(config)# ip mrm manager test1
           

          Specifies the name of an MRM test to be created or modified, and enters MRM manager configuration mode.

          • The test name is used to start, stop, and monitor a test.

          • From MRM manager configuration mode, you specify the parameters of the test.

           
          Step 4 manager type number group ip-address


          Example:
          Device(config-mrm-manager)# manager gigabitethernet 0/0/0 group 239.1.1.1
           

          Specifies which interface on the device is the Manager, and specifies the multicast group address the Test Receiver will listen to.

           
          Step 5 beacon [interval seconds] [holdtime seconds][ttl ttl-value]


          Example:
          Device(config-mrm-manager)# beacon interval 60
           

          (Optional) Changes the frequency, duration, or scope of beacon messages that the Manager sends to the Test Sender and Test Receiver.

          • By default, beacon messages are sent at an interval of 60 seconds.

          • By default, the duration of a test period is 86400 seconds (1 day).

          • By default, the TTL is 32 hops.

           
          Step 6 udp-port test-packet port-number ] status-report port-number ]


          Example:
          Device(config-mrm-manager)# udp-port test-packet 20202
           

          (Optional) Changes the UDP port numbers to which the Test Sender sends test packets or the Test Receiver sends status reports.

          • Use the optional test-packet keyword and port-number argument to change the UDP port to which the Test Sender sends test packets. The port number must be even if the packets are Real-Time Transport Protocol (RTP)-encapsulated. The range is from 16384 to 65535.

          • By default, the Test Sender uses UDP port number 16834 to send test packets.

          • Use the optional status-report keyword and port-number argument to change the UDP port to which the Test Receiver sends status reports. The port number must be odd if the packets are RTP Control Protocol (RTCP)-encapsulated. The range is from 16834 to 65535.

          • By default, the Test Receiver uses UDP port number 65535 to send status reports.

           
          Step 7 senders access-list [packet-delay milliseconds] [rtp| udp] [target-only| all-multicasts| all-test-senders]


          Example:
          Device(config-mrm-manager)# senders 1 packet-delay 400 udp all-test-senders
           

          Establishes Test Senders for MRM tests.

          • Use the optional packet-delay keyword and milliseconds argument to specify the delay between test packets (in milliseconds). The range is from 50 to 10000. The default is 200 milliseconds, which results in 5 packets per second.

          • Use the optional rtp keyword or udp keyword to specify the encapsulation of test packets, either Real-Time Transport Protocol (RTP) encapsulated or User Datagram Protocol (UDP) encapsulated. By default, test packets are RTP-encapsulated.

          • Use the optional target-only keyword to specify that test packets are sent out on the targeted interface only (that is, the interface with the IP address that is specified in the Test Sender request target field). By default, test packets are sent out on all interfaces that are enabled with IP multicast.

          • Use the optional all-multicasts keyword to specify that the test packets are sent out on all interfaces that are enabled with IP multicast. This is the default method for sending test packets.

          • Use the optional all-test-senders keyword to specify that test packets are sent out on all interfaces that have test-sender mode enabled. By default, test packets are sent out on all interfaces that are enabled with IP multicast.

           
          Step 8 receivers access-list sender-list access-list [packet-delay]


          Example:
          Device(config-mrm-manager)# receivers 1 sender-list 3
           

          Establishes Test Receivers for MRM.

          Note   

          Although the Cisco IOS CLI parser accepts the command entered without the sender-list access-list keyword-argument pair, this keyword-argument pair is not optional. For an MRM test to work, you must specify the sources that the Test Receiver should monitor using the sender-list keyword and access-list argument.

          • Use the sender-list keyword and access-list to specify the sources that the Test Receiver should monitor. If the named or numbered access list matches any access list specified in the senders command, the associated packet-delay milliseconds keyword and argument of that senders command are used in the MRM test. Otherwise, the receivers command requires that a delay be specified for the packet-delay argument.

          • Use the optional packet-delay argument to specify the delay between test packets (in milliseconds). The range is from 50 to 10000. If the sender-list access list matches any access list specified in a senders command, the associated packet-delay milliseconds keyword and argument of that senders command are used in this command. Otherwise, the receiverscommand requires that a delay be specified for the packet-delay argument.

           
          Step 9 receivers access-list [window seconds] [report-delay seconds] [loss percentage] [no-join] [monitor | poll]


          Example:
          Device(config-mrm-manager)# receivers 1 window 7 report-delay 30
           

          (Optional) Modifies the parameters of Test Receivers.

          • Use the optional window keyword and seconds argument to specify the duration (in seconds) of a test period. This is a sliding window of time in which the packet count is collected, so that the loss percentage can be calculated. The range is from 1 to 10. The default is 5 seconds.

          • Use the optional report-delay keyword and seconds argument to specify the delay (in seconds) between status reports. The delay prevents multiple Test Receivers from sending status reports to the Manager at the same time for the same failure. This value is relevant only if there are multiple Test Receivers. The range is from 1 to 60. The default is 1 second.

          • Use the optional loss keyword and percentage argument to specify the threshold percentage of packet loss required before a status report is triggered. The range is from 0 to 100. The default is 0 percent, which means that a status report is sent for any packet loss.

          • Use the optional no-join keyword to specify that the Test Receiver does not join the monitored group. The default is that the Test Receiver joins the monitored group.

          • Use either the optional monitor or poll keyword to specify whether the Test Receiver monitors the test group or polls for receiver statistics. The monitor keyword means the Test Receiver reports only if the test criteria are met. The poll keyword means the Test Receiver sends status reports regularly, whether test criteria are met or not. The default is the behavior set with the monitor keyword.

           

          Conducting an MRM Test and Viewing Results

          From the device playing the Manager role, you can start and stop the MRM test. To start and subsequently stop your MRM test, perform this task.

          When the test begins, the Manager sends a unicast control packet to the Test Sender and Test Receiver, and then the Manager starts sending beacons. The Test Sender and Test Receiver send acknowledgments to the Manager and begin sending or receiving test packets. If an error occurs, the Test Receiver sends an error report to the Manager, which immediately displays the report.

          SUMMARY STEPS

            1.    enable

            2.    clear ip mrm status-report [ip-address]

            3.    show ip mrm interface [type number]

            4.    show ip mrm manager [test-name]

            5.    mrm test-name start

            6.    mrm test-name stop

            7.    show ip mrm status-report [ip-address]


          DETAILED STEPS
             Command or ActionPurpose
            Step 1 enable


            Example:
            Device> enable
             

            Enables privileged EXEC mode.

            • Enter your password if prompted.

             
            Step 2 clear ip mrm status-report [ip-address]


            Example:
            Device# clear ip mrm status-report 172.16.0.0
             

            (Optional) Clears the MRM status report cache.

             
            Step 3 show ip mrm interface [type number]


            Example:
            Device# show ip mrm interface Ethernet 1
             

            (Optional) Displays MRM information related to interfaces.

            • Use this command before starting an MRM test to verify the interfaces are participating in MRM, in which roles, and whether the interfaces are up or down.

             
            Step 4 show ip mrm manager [test-name]


            Example:
            Device# show ip mrm manager test1
             

            (Optional) Displays information about MRM tests.

            • Use this command before starting an MRM test to verify MRM status information and the parameters configured for an MRM test.

             
            Step 5 mrm test-name start


            Example:
            Device# mrm test1 start
             

            Starts the MRM test.

             
            Step 6 mrm test-name stop


            Example:
            Device# mrm test1 stop
             

            Stops the MRM test.

             
            Step 7 show ip mrm status-report [ip-address]


            Example:
            Device# show ip mrm status-report
             

            (Optional) Displays the status reports in the MRM status report cache.

             

            Configuration Examples for MRM

            Configuring MRM Example

            The figure illustrates a Test Sender, a Test Receiver, and a Manager in an MRM environment. The partial configurations for the three devices follow the figure.

            Figure 2. MRM Example Topology

            Test Sender Configuration

            interface GigabitEthernet 0/0/0 
 ip mrm test-sender

            Test Receiver Configuration

            interface GigabitEthernet 0/0/0 
 ip mrm test-receiver

            Manager Configuration

            ip mrm manager test1 
manager GigabitEthernet 1/0/0 group 239.1.1.1 
senders 1
receivers 2 sender-list 1 
! 
access-list 1 permit 10.1.1.2 
access-list 2 permit 10.1.4.2

            Additional References

            Related Documents

            Related Topic

            Document Title

            Cisco IOS commands

            Cisco IOS Master Commands List, All Releases

            IP multicast commands

            Cisco IOS IP Multicast Command Reference

            Standards and RFCs

            Standard/RFC

            Title

            draft-ietf-mboned-mrm-use-00.txt

            Justification and Use of the Multicast Routing Monitor (MRM) Protocol

            MIBs

            MIB

            MIBs Link

            —

            To locate and download MIBs for selected platforms, Cisco IOS XE software releases, and feature sets, use Cisco MIB Locator found at the following URL:

            http:/​/​www.cisco.com/​go/​mibs

            Technical Assistance

            Description

            Link

            The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

            http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

            Feature Information for Using the Multicast Routing Monitor

            The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

            Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.
            Table 1 Feature Information for Using the Multicast Routing Monitor

            Feature Name

            Releases

            Feature Information

            Multicast Routing Monitor (MRM)

            12.0(5)S

            12.2(15)T

            The Multicast Routing Monitor is a network fault detection and isolation mechanism for administering a multicast routing infrastructure.