Configure IPv4 Multicast
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Configure IPv4 Multicast

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Configure IPv4 Multicast

Configure IPv4 multicast for an Advanced Routing Engine.
The Advanced Routing Engine supports IPv4 multicast for a logical router. You should be familiar with IP Multicast, IGMP, and PIM concepts.
IPv4 multicast on an Advanced Routing Engine supports features not supported on the legacy routing engine:
  • IGMP static join, which is the ability to specify a static IGMPv3 or IGMPv2 receiver on an interface. The corresponding PIM Join message is sent upstream.
  • Protocol Independent Multicast (PIM) supports Reverse-Path Forwarding (RPF) lookup modes: MRIB only, URIB only, and MRIB-then-URIB.
IPv4 multicast does not support IGMPv1.
When you configure IPv4 multicast, you Create Multicast Routing Profiles for PIM interface timers and IGMP interface queries to make your configuration easier and consistent. You can create multicast route maps to control PIM group permissions.
You can also Create an IPv4 MRoute if you want unicast traffic to take a different route from multicast traffic.
  1. Select
    Network
    Routing
    Logical Routers
    and select a logical router.
  2. Select
    Multicast
    and
    enable multicast protocol
    .
  3. Configure general PIM parameters for the logical router.
    1. Select
      PIM
      General
      and
      Enable
      PIM.
    2. Select the
      RPF lookup mode
      , which determines where the logical router looks to find the outgoing interface to reach the source address contained in the multicast packet. If the outgoing interface stored in the RIB matches the interface on which the multicast packet arrived, the logical router accepts and forwards the packet; otherwise, it drops the packet.
      • mrib-only
        —Look in multicast RIB only.
      • mrib-then-urib
        —Look in multicast RIB first; if route is not present in multicast RIB, then look in unicast RIB.
      • urib-only
        —Look in unicast RIB only.
      The
      RPF lookup mode
      also controls where to do route lookup to select the route to use for the PIM Join.
    3. For the
      Interface General Timer
      , select a PIM
      Interface Timer Profile
      or create a new IPv4 PIM Interface Timer profile; default is
      None
      .
    4. Specify the
      Route Age Out Time (sec)
      —the number of seconds that a multicast route remains in the mRIB after the session ends between a multicast group and a source; range is 210 to 7,200; default is 210.
    5. To configure Source-Specific Multicast (SSM), in
      Multicast SSM Range
      select a prefix list (or create a new one) that specifies the source addresses allowed to deliver multicast traffic to the receiver; default is
      None (no prefix list)
      .
    6. To configure the Shortest-Path Tree (SPT) threshold for a multicast group or prefix,
      Add
      a
      Group Address
      (multicast group or prefix for which you are specifying the distribution tree) by selecting a Prefix List or creating a new one.
    7. Specify the
      Threshold
      rate in kilobits per second (kbps); if multicast traffic for the multicast group/prefix arrives at the logical router faster than this threshold rate, routing to the specified group/prefix switches from shared tree (sourced from the Rendezvous Point [RP]) to SPT distribution:
      • 0 (switch on first data packet)
        (default)—The logical router switches from shared tree to SPT for the group/prefix when the logical router receives the first data packet for the group/prefix.
      • Enter the total number of kilobits per second that can arrive for the multicast group/prefix at any interface and over any time period, upon which the logical router switches to SPT distribution for that multicast group or prefix; range is 0 to 4,294,967,295.
      • never (do not switch to spt)
        —The PIM router continues to use the shared tree to forward packets to the multicast group/prefix.
  4. Specify PIM group permissions to control which PIM Join messages and Register messages the logical router accepts, and which multicast traffic the logical router forwards.
    1. Select
      PIM
      Group Permissions
      .
    2. To control packets to certain destination multicast groups from certain sources (S,G) to transit the logical router, for
      Source Group List
      , select an Access List that you created or create a new one. The access list can be an extended access list where the source specifies the multicast source and the destination specifies the multicast group. Default is
      None (no access list)
      .
      When you modify PIM Group Permissions by removing or changing the Source Group access list, the new permission does not retroactively clear multicast routes form the multicast RIB table (mRIB) or multicast FIB table (mFIB) for existing flows. To change entries for existing flows in the mRIB or mFIB, you would need to force a Leave or clear mroute entry.
  5. Configure PIM characteristics for an interface.
    1. Select
      PIM
      Interfaces
      and
      Add
      an interface by
      Name
      .
    2. Enter a helpful
      Description
      of the interface.
    3. Specify the
      DR Priority
      (Designated Router priority) of the interface to control which router forwards PIM Join messages, PIM Register messages, and Prune messages to the Rendezvous Point (RP); range is 1 to 4,294,967,295; default is 1. Of the PIM devices on a LAN, if DR Priority is configured, the device with the highest priority value is elected the DR.
    4. Send BSM
      to allow propagation of Bootstrap Messages (enabled by default).
      The Advanced Routing Engine cannot act as a BSR, but can send and relay BSM messages.
    5. The
      Timer Profile
      for the interface is inherited from the General PIM section unless you override that by selecting an IPv4 PIM Interface Timer profile; default is
      None
      .
    6. Specify a
      Neighbor Filter
      using an access list you created or create a new access list to specify the prefixes of devices that are allowed to become or denied from becoming PIM neighbors of the logical router.
    7. Click
      OK
      .
  6. (
    ASM only
    ) Configure a PIM Rendezvous Point (RP) for an Any-Source Multicast (ASM) environment.
    You can configure a Candidate RP and a Static RP; they are not mutually exclusive.
    1. Select
      PIM
      Rendezvous Point
      .
    2. Select the local
      RP Type
      :
      Static RP
      or
      Candidate RP
      ; default is
      None
      .
    3. If you choose
      Static RP
      , this establishes a static mapping of an RP to multicast groups. You must explicitly configure the same RP on other PIM routers in the PIM domain. Configure the following:
      • Select the RP
        Interface
        where the RP receives and sends multicast packets. Valid interface types are Layer3 interfaces (which include Ethernet, VLAN, loopback, Aggregate Ethernet (AE), tunnel, and subinterfaces).
      • Select the
        Address
        of the interface; the IP addresses of the interface you selected populate the list.
      • Select
        Override learned RP for the same group
        so that this static RP serves as RP instead of the RP elected for the groups in the Group List.
      • Specify the
        Group List
        of multicast groups for which the static RP acts as the RP by selecting an Access List or creating a new access list. Default is
        None (no access list)
        .
    4. If you choose
      Candidate RP
      :
      • Select the
        Interface
        where the candidate RP receives and sends multicast packets. Valid interface types are Layer3 interfaces (which include Ethernet, VLAN, loopback, Aggregate Ethernet (AE), tunnel, and subinterfaces).
      • Select the
        Address
        of the interface.
      • Specify the
        Priority
        of the candidate RP; range is 0 to 255; default is 192. A lower priority value indicates a higher priority.
      • Specify the
        Advertisement Interval
        , the frequency (in seconds) at which the candidate RP sends advertisements to other routers; range is 1 to 26,214; default is 60.
      • To control the groups that the candidate RP accepts, select a
        Group List
        , which is an IPv4 access list you created, or create a new access list. Default is
        None (no access list)
        . If no access list is applied, the logical router starts advertising itself as the RP for all groups.
    5. Add
      an
      IPv4 Address
      of the remote (external) RP.
    6. Select a
      Group List
      to specify the multicast groups for which the remote RP acts as the RP or create a new access list. Default is
      None (no access list)
      .
    7. Select
      Override
      if you want the remote RP you statically configured to serve as RP instead of an RP that is dynamically learned (elected) for the groups in the Group List.
    8. Click
      OK
      .
  7. Click
    OK
    to save PIM settings.
  8. Configure IGMP on interfaces that face a multicast receiver.
    1. Select
      IGMP
      and
      enable IGMP
      .
    2. To configure a dynamic IGMP interface, select
      Dynamic
      .
      1. Add
        an
        Interface
        by selecting one from the list.
      2. Select the IGMP
        Version
        :
        2
        or
        3
        .
      3. Select the
        Robustness
        value in the range 1 to 7; default is 2.
        The (Robustness * QueryInterval) + MaxQueryResponseTime determines how long a Join message is valid on the logical router. If the logical router receives a Leave Group message, Robustness * LastMemberQueryInterval is the length of time that the logical router waits before deleting the Leave Group entry. Increase the Robustness value if the subnet on which this logical router is located is prone to losing packets. For Join messages, a Robustness value of 1 is ignored. For Leave Group messages, the logical router uses the Robustness value as the Last Member Query Count also.
      4. For
        Group Filter
        , select an access list or create a new access list to control the sources and groups for which the interface will accept IGMP Joins; default is
        None (no access list)
        .
      5. For
        Max Groups
        , enter the maximum number of groups that IGMP can process simultaneously for the interface. Range is 1 to 65,535; default is
        unlimited
        , which means the highest value in the range.
      6. For
        Max Sources
        , enter the maximum number of sources that IGMP can process simultaneously for the interface. Range is 1 to 65,535; default is
        unlimited
        , which means the highest value in the range.
      7. For
        Query Profile
        , select an IGMP Interface Query profile you created or create a new one to apply to the interface; default is
        None
        .
      8. Select
        drop IGMP packets without Router Alert option
        to require that incoming IGMPv2 or IGMPv3 packets have the IP Router Alert Option, RFC 2113, or they will be dropped. (Default is disabled.)
      9. Click
        OK
        to save the dynamic IGMP interface.
    3. To configure a static IGMP interface, select
      Static
      .
      1. Add
        a static interface by
        Name
        .
      2. Select the
        Interface
        to be the static IGMP interface.
      3. Enter the multicast
        Group Address
        of the static IGMP members.
      4. Enter the
        Source Address
        of the sender transmitting multicast traffic to the multicast group (S,G). Traffic for this (S,G) combination is allowed on the static IGMP interface.
      5. Click
        OK
        to save the static IGMP interface.
  9. Click
    OK
    to save the multicast configuration.
  10. Commit
    .

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