IS-IS MTR for Multicast Address Family

The IS-IS MTR for Multicast Address Family feature enables Intermediate System to Intermediate System (IS-IS) protocol to support Multitopology Routing (MTR) in the following ways:

  • Advertise topology-specific routes to protocol peers

  • Perform best path calculation on multiple topologies

  • Update routes for each of the supported topologies in the global Routing Information Base (RIB)

  • Support configuration commands related to MTR

  • Support multiple multicast topologies

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 at the end of this module.

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.

Information About IS-IS MTR for Multicast Address Family

IS-IS MTR for Multicast Address Family Overview

The IS-IS MTR for Multicast Address Family feature supports multiple IPv4 multicast topologies, which are incongruent from unicast topologies in the global address space.

Routing Protocol Support for MTR

You must enable IP routing on the device for Multitopology Routing (MTR) to operate. MTR supports static and dynamic routing in Cisco software. You can enable dynamic routing per topology to support interdomain and intradomain routing. Route calculation and forwarding are independent for each topology. MTR support is integrated into Cisco software for the following protocols:
  • Enhanced Interior Gateway Routing Protocol (EIGRP)
  • Integrated Intermediate System-to-Intermediate System (IS-IS)

You must apply the per-topology configuration in router address family configuration mode of the global routing process (router configuration mode). The address family and the subaddress family are specified when the device enters address family configuration mode. You can specify the topology name and topology ID by entering the topology command in address family configuration mode. You can configure each topology with a unique topology ID under the routing protocol. The topology ID is used to identify and group Network Layer Reachability Information (NLRI) for each topology in updates for a given protocol. In EIGRP and IS-IS, you enter the topology ID during the first configuration of the topology command for a class-specific topology.

You can configure class-specific topologies with metrics that are different than the base topology. Interface metrics configured on the base topology can be inherited by the class-specific topology. Inheritance occurs if no explicit inheritance metric is configured in the class-specific topology. By default, interfaces are not included in nonbase topologies. For routing protocol support for EIGRP and IS-IS, you must explicitly configure a nonbase topology on an interface. You can override the default behavior by using the all-interfaces command in address family topology configuration mode. The all-interfaces command causes the nonbase topology to be configured on all interfaces of the device that are part of the default address space in which the topology is configured.

How to Configure IS-IS MTR for Multicast Address Family

Configuring a Multicast Topology

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ip multicast-routing

    4.    ip multicast rpf multitopology

    5.    global-address-family ipv4 multicast

    6.    topology {base | topology-name}

    7.    Repeat Step 6 to configure another global topology instance.

    8.    exit

    9.    interface type number

    10.    ip address ip-address mask [secondary]

    11.    ip pim sparse-dense-mode

    12.    ip router isis

    13.    topology ipv4 multicast {topology-name [disable] | base}

    14.    exit

    15.    Repeat Steps 9 through 14 to configure each interface in use.

    16.    end


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example: 
    Device> enable
     
    Enables privileged EXEC mode.
    • Enter your password if prompted.
     
    Step 2configure terminal


    Example: 
    Device# configure terminal
     

    Enters global configuration mode.

     
    Step 3ip multicast-routing


    Example: 
    Device(config)# ip multicast-routing
     

    Enables IP multicast routing.

     
    Step 4 ip multicast rpf multitopology


    Example: 
    Device(config)# ip multicast rpf multitopology
     

    Enables multicast Reverse Path Forwarding (RPF) lookup in multiple topologies.

     
    Step 5global-address-family ipv4 multicast


    Example: 
    Device(config)# global-address-family ipv4 multicast
     

    Enters global address family configuration mode to configure a topology.

     
    Step 6 topology {base | topology-name}

    Example: 
    Device(config-af)# topology live
     

    Configures a global topology instance.

     
    Step 7 Repeat Step 6 to configure another global topology instance.  

    —

     
    Step 8 exit


    Example: 
    Device(config-af)# exit
     

    Exits global address family configuration mode and returns to global configuration mode.

     
    Step 9interface type number


    Example: 
    Device(config)# interface Gigabitethernet 1/0
     

    Enters interface configuration mode for the specified interface type and number.

     
    Step 10ip address ip-address mask [secondary]


    Example: 
    Device(config-if)# ip address 209.165.200.225 255.255.255.224
     

    Sets a primary or secondary IP address for an interface.

     
    Step 11ip pim sparse-dense-mode


    Example: 
    Device(config-if)# ip pim sparse-dense-mode
     

    Enables PIM sparse dense mode on the interface.

     
    Step 12ip router isis


    Example: 
    Device(config-if)# ip router isis
     

    Configures an Intermediate System-to-Intermediate System (IS-IS) routing process for IP on the interface.

     
    Step 13topology ipv4 multicast {topology-name [disable] | base}


    Example: 
    Device(config-if)# topology ipv4 multicast live
     

    Configures a topology instance on an interface.

     
    Step 14exit


    Example: 
    Device(config-if)# exit
     

    Exits interface configuration mode and returns to global configuration mode.

     
    Step 15 Repeat Steps 9 through 14 to configure each interface in use.  

    —

     
    Step 16 end


    Example: 
    Device(config)# end
     

    Ends the current configuration session and returns to privileged EXEC mode.

     

    Activating an MTR Topology by using IS-IS

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    router isis

      4.    net net1

      5.    metric-style wide [transition] [level-1 | level-2 | level-1-2]

      6.    address-family ipv4 multicast

      7.    topology topology-name tid number

      8.    end


    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 3router isis


      Example: 
      Device(config)# router isis
       

      Enables the IS-IS routing protocol and specifies an IS-IS process.

       
      Step 4net net1


      Example: 
      Device(config-router)# net 31.3131.3131.3131.00
       

      Configures an IS-IS network entity (NET) for the routing process.

       
      Step 5 metric-style wide [transition] [level-1 | level-2 | level-1-2]


      Example: 
      Device(config-router)# metric-style wide
       

      Configures a router running IS-IS so that it generates and accepts only new-style type-length-value (TLV) objects.

       
      Step 6 address-family ipv4 multicast


      Example: 
      Device(config-router)# address-family ipv4 multicast
       

      Enters router address family configuration mode under IS-IS router configuration mode.

       
      Step 7topology topology-name tid number


      Example: 
      Device(config-router-af)# topology live tid 10
       

      Enters router address family configuration mode under IS-IS router configuration mode.

       
      Step 8 end


      Example: 
      Device(config-router-af)# end
       

      Exits router address family configuration mode and returns to privileged EXEC mode.

       

      Verifying IS-IS MTR for Multicast Address Family

      SUMMARY STEPS

        1.    enable

        2.    show ip multicast topology [multicast topology-name]


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example: 
        Device> enable
         
        Enables privileged EXEC mode.
        • Enter your password if prompted.
         
        Step 2 show ip multicast topology [multicast topology-name]


        Example: 
        Device# show ip multicast topology multicast live
         

        Displays multicast topology information.

         

        Configuration Examples for IS-IS MTR for Multicast Address Family

        Example: Multicast Topology Configuration

        The following example shows how to configure IS-IS MTR for Multicast Address Family: 

        Device> enable
Device# configure terminal
Device(config)# ip multicast-routing
Device(config)# ip multicast rpf multitopology
Device(config)# global-address-family ipv4 multicast 
Device(config-af)# topology live
Device(config-af-topology)# exit
Device(config-af)# exit
Device(config)# interface Gigabitethernet 1/0
Device(config-if)# ip address 10.1.1.1 255.255.255.0
Device(config-if)# ip pim sparse-dense-mode
Device(config-if)# ip router isis
Device(config-if)# topology ipv4 multicast live

        Example: Activating an MTR Topology by using IS-IS

        The following example shows how to activate an MTR topology by using IS-IS: 

        Device> enable
Device# configure terminal
Device(config)# router isis
Device(config-router)# net 31.3131.3131.3131.00
Device(config-router)# metric-style wide
Device(config-router)# address-family ipv4 multicast 
Device(config-router-af)# topology live tid 10

        Additional References for IS-IS MTR for Multicast Address Family

        Related Documents

        Related Topic

        Document Title

        Cisco IOS commands

        Cisco IOS Master Command List, All Releases

        Multitopology Routing (MTR) commands

        Cisco IOS Multitopology Routing Command Reference

        Intermediate System-to-Intermediate System (IS-IS) commands

        Cisco IOS IP Routing: IS-IS Command Reference

        IS-IS concepts and tasks

        IP Routing: IS-IS Configuration Guide

        Configuring a multicast topology

        Multitopology Routing Configuration Guide

        Standards and RFCs

        Standard/RFC

        Title

        RFC 5120

        M-ISIS: Multitopology (MT) Routing in Intermediate System-to-Intermediate Systems (IS-ISs)

        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 IS-IS MTR for Multicast Address Family

        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 IS-IS MTR for Multicast Address Family

        Feature Name

        Releases

        Feature Information

        IS-IS MTR for Multicast Address Family

        15.1(2)SY

        The IS-IS MTR for Multicast Address Family feature supports single and multiple IPv4 multicast topologies which are incongruent from unicast topologies in the global address space.