Configuring IGMP on a VLAN interface for a Layer 3 VRF

Use this procedure to configure IGMP for each VLAN interface to enable the interface to perform multicast operations.

IGMPv2 at the VLAN level is the default setting, with no other configuration required. You only need to enable IGMPv3. You must enable SSM snoop before you configure IGMP version 3, and you must enable both ssm-snoop and snooping 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.

Note

Note

You cannot enable IP PIM when IP Multicast over Fabric Connect is enabled on the VLAN.

Before you begin

  • You must configure the required SPBM IS-IS infrastructure.

  • You must configure a VRF and IP VPN instance with an I-SID on the switch.

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

  • You must enable IP Multicast over Fabric Connect for a Layer 3 VSN.

About this task

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.

Procedure

  1. In the navigation pane, expand Configuration > VRF Context View.
  2. Click Set VRF Context View.
  3. Choose a VRF name.
  4. Click Launch VRF Context View.
  5. In the navigation pane, expand Configuration > VLAN.
  6. Click VLANs.
  7. Select the desired VLAN from the listing.
  8. Click the IP button.
  9. Click the IGMP tab.
  10. Optional: If you want to enable SsmSnoopEnable, select the SsmSnoopEnable box.
  11. Optional: If you want to enable Snoop, select the SnoopEnable box.
  12. Optional: In the Version box, select the correct IGMP version.

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

  13. Optional: Select SnoopQuerierEnable, to enable Snoop Querier. Only select this option, if you want to configure an address for the IGMP queries.
  14. Optional: In the SnoopQuerierAddr box, type an IP address, if you want to configure a snoop querier address.
    Note

    Note

    If the SPBM bridge connects to an edge switch, it can be necessary to add an IGMP query address. If you omit adding a query address, the SPB bridge sends IGMP queries with a source address of 0.0.0. Some edge switch models do not accept a query with a source address of 0.0.0.0.

IGMP field descriptions

Use the data in the following table to use the IGMP tab.

Name

Description

QueryInterval

Configures the frequency (in seconds) at which the IGMP host query packets transmit on the interface. The range is from 1–65535 and the default is 125.

QueryMaxResponseTime

Configures the maximum response time (in tenths of a second) advertised in IGMPv2 general queries on this interface. You cannot configure this value for IGMPv1.

Smaller values allow a router to prune groups faster. The range is from 0–255 and the default is 100 tenths of a second (equal to 10 seconds.)

Important:

You must configure this value lower than the QueryInterval.

Robustness

Configure this parameter to tune for the expected packet loss of a network. This value is equal to the number of expected query packet losses for each serial query interval, plus 1. If you expect the network to lose query packets, increase the robustness value.

The range is from 2–255 and the default is 2. The default value of 2 means that the switch drops one query for each query interval without the querier aging out.

LastMembQueryIntvl

Configures the maximum response time (in tenths of a second) inserted into group-specific queries sent in response to leave group messages. This value is also the time between group-specific query messages. You cannot configure this value for IGMPv1.

Decreasing the value reduces the time to detect the loss of the last member of a group. The range is from 0–255 and the default is 10 tenths of a second.

Configure this parameter to values greater than 3. If you do not require a fast leave process, use values greater than 10. (The value 3 is equal to 0.3 seconds, and 10 is equal to 1 second.)

SnoopEnable

Enables or disables snoop.

SsmSnoopEnable

Enables or disables support for SSM on the snoop interface.

ProxySnoopEnable

Enables or disables proxy snoop.

Version

Configures the version of IGMP (1, 2, or 3) that you want to use on this interface. For IGMP to function correctly, all routers on a LAN must use the same version. The default is version 2.

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.

FastLeaveEnable

Enables or disables fast leave on the interface.

StreamLimitEnable

Enables or disables stream limitation on this VLAN.

Maximum Number Of Stream

Configures the maximum number of streams allowed on this VLAN. The range is from 0–65535 and the default is 4.

Current Number Of Stream

Displays the current number of streams. This value is a read-only value.

FastLeavePortMembers

Selects the ports that are enabled for fast leave.

SnoopMRouterPorts

Selects the ports in this interface that provide connectivity to an IP multicast router.

DynamicDowngradeEnable

Configures if the switch downgrades the version of IGMP to handle older query messages. If the switch downgrades, the host with IGMPv3 only capability does not work. If you do not configure the switch to downgrade the version of IGMP, the switch logs a warning. The default value is selected (enabled), which means the switch downgrades to the oldest version of IGMP on the network.

CompatibilityModeEnable

Enables or disables v2-v3 compatibility mode. The default value is clear (disabled), which means IGMPv3 is not compatible with IGMPv2.

ExplicitHostTrackingEnable

Enables or disables IGMPv3 to track hosts per channel or group. The default is disabled. You must select this field if you want to use fast leave for IGMPv3.

SnoopQuerierEnable

Enables Snoop Querier. The default is disabled.

When you enable IGMP Layer 2 Querier, Layer 2 switches in your network can snoop IGMP control packets exchanged with downstream hosts and upstream routers. The Layer 2 switches then generate the Layer 2 MAC forwarding table, used for switching sessions and multicast traffic regulation, and provide the recurring queries required to maintain IGMP groups.

Enable Layer 2 Querier on only one node in the VLAN.

SnoopQuerierAddr

Specifies the pseudo IP address of the IGMP Snoop Querier. The default IP address is 0.0.0.0.

If the SPBM bridge connects to an edge switch, it can be necessary to add an IGMP query address. If you omit adding a query address, the SPBM bridge sends IGMP queries with a source address of 0.0.0.0. Some edge switch models do not accept a query with a source address of 0.0.0.0.