Configuring Layer 2 VSN IP Multicast over Fabric Connect

Use this procedure to configure IP Multicast over Fabric Connect for Layer 2 VSN functionality. With Layer 2 VSN IP Multicast over Fabric Connect, multicast traffic remains in the same Layer 2 VSN across the SPBM cloud.

Before you begin

  • You must configure the required SPBM and IS-IS infrastructure, which includes the creation of SPBM B-VLANs.

  • You must create the customer VLANs (C-VLANs) and add slots/ports.

  • You must assign the same I-SID to the C-VLANs on all the BEBs where you configure the C-VLAN.

  • You must enable IP Multicast over Fabric Connect globally.

About this task

Traffic is only delivered to UNIs on the Layer 2 VSN where the switch receives IGMP joins and reports. Traffic does not cross the Layer 2 VSN boundary.

Configuring ip igmp snooping on a VLAN that has an I-SID configured (a C-VLAN) automatically enables that VLAN for IP Multicast over Fabric Connect services. No explicit configuration exists separate from that to enable Layer 2 VSN IP Multicast over Fabric Connect.

SPBM supports enabling IGMP Snooping on a C-VLAN, but it does not support enabling Protocol Independent Multicast (PIM) on a C-VLAN. If you enable IGMP snooping on a C-VLAN, then its operating mode is Layer 2 Virtual Services Network with IGMP support on the access networks for optimized forwarding of IP multicast traffic in a bridged network.

The switch only supports IPv4 multicast traffic.

Procedure

  1. Enter VLAN Interface Configuration mode:

    enable

    configure terminal

    interface vlan <1–4059>

  2. Enable proxy snoop:

    ip igmp proxy

  3. Enable IGMP snooping:

    ip igmp snooping

  4. Optional: If you want to configure an address for the IGMP queries, enter the following command:

    ip igmp snoop-querier-addr <A.B.C.D>

    This step is not always required. The IGMP Querier on the BEB uses a source address 0.0.0.0 by default. When you do not configure this, a BEB sends IGMP queries on the UNI ports with 0.0.0.0 as the source IP address. Some Layer 2 edge switches do not support a 0.0.0.0 querier. You can use a fictitious IP address as the querier address, and use the same address on all BEBs in the network.

  5. Optional: Enable IGMPv3 at a VLAN level by enabling SSM-snooping and IGMPv3:

    ip igmp ssm-snoop

    ip igmp version 3

    You must enable SSM snoop before you configure IGMP version 3 and both ssm-snoop and snooping must be enabled for IGMPv3.

    For IGMP Snooping, ensure that the IGMP version used by multicast hosts and other devices in the network is the same as the IGMP version configured on the IGMP Snooping VLAN, or that you enable compatibility mode.

Example

Enable IGMPv2 at a VLAN level:
Switch:1>enable
Switch:1#configure terminal
Switch:1(config-if)#interface vlan 501
Switch:1(config-if)#ip igmp proxy
Switch:1(config-if)#ip igmp snooping
Switch:1(config-if)#ip igmp snoop-querier-addr 192.0.2.1

Enable IGMPv3 at a VLAN level:

Switch:>enable
Switch:#configure terminal
Switch:1(config)#interface vlan 2256
Switch:1(config-if)#ip igmp proxy
Switch:1(config-if)#ip igmp snooping
Switch:1(config-if)#ip igmp snoop-querier-addr 192.0.2.1
Switch:1(config-if)#ip igmp version 3
Switch:1(config-if)#ip igmp ssm-snoop