Define IGMP-based multicast forwarding

You can configure IGMP-based multicast forwarding for a specified Engine element.

IGMP-based multicast forwarding (IGMP proxying) is implemented on the Engine based on RFC 4605, and is supported only in tree topology networks. While RFC 4605 includes support for source-specific multicast (SSM) with IGMP version 3, SSM is not supported with IGMP-based multicast forwarding. However, you can configure Access rules to filter multicast traffic based on the source.

The Engine maintains a membership database of subscriptions from downstream networks and sends unsolicited reports or leave notifications on the upstream interface when the subscription database changes. It also sends IGMP membership reports in response to queries on the upstream interface.

Note: Make sure your IPv4 Access rules allow this traffic to pass through the Engine.

Steps

  1. Right-click a SMCaaS, then select Edit <element type>.
  2. Browse to Routing > Multicast Routing.
  3. Select IGMP Proxy as the Multicast Routing Mode.
  4. (Optional) Select the Upstream Interface and the IGMP Querier Settings for it.
    • If the multicast servers and the hosts are in the local networks, or if you want to limit the multicast to the local networks, it is not necessary to define the Upstream Interface. In that case, leave Not Set selected for Upstream Interface.
    • (Engine Clusters only) You can only select as the Upstream Interface an interface that has a Cluster Virtual IP Address (CVI). You cannot select a Heartbeat Interface as the Upstream Interface.
    • You might need to select a specific IGMP Querier Settings element, for example, to troubleshoot multicast accessibility on hosts, or if some hosts use an earlier IGMP version.
  5. Click Add to define Downstream Interfaces.
    The Engine periodically queries the downstream networks for hosts that want to join or leave the multicast host group.
    A new entry appears in the table.
  6. Click the Interface cell and select the Downstream Interface from the list.
    • You can use each interface only once in the IGMP proxy configuration.
    • (Engine Clusters only) The interface selected as a Downstream Interface must have Node Dedicated IP Addresses (NDIs) and cannot be a Heartbeat Interface. It is recommended that the NDIs increment in the same order on each node — for example, 192.168.1.10 and 192.168.2.10 for node A, and 192.168.1.11 and 192.168.2.11 for node B.
    Note: The downstream interfaces must have the lowest IP addresses among all IGMP queries in the local networks.
  7. Click the IGMP Querier Settings cell, then select the IGMP Querier Settings element that uses the IGMP version for the downstream interface.
    You might need to select a specific IGMP Querier Settings element, for example, to troubleshoot multicast accessibility on hosts, or if some hosts use an earlier IGMP version.
  8. Click Save and Refresh to transfer the changed configuration.