igmp enable

Function

The igmp enable command enables IGMP on an interface.

The undo igmp enable command disables IGMP on an interface.

By default, IGMP is disabled on an interface.

Format

igmp enable

undo igmp enable

Parameters

None

Views

GE interface view, XGE interface view, MultiGE interface view, 25GE interface view, 40GE interface view, 100GE interface view, Eth-Trunk interface view, GE sub-interface view, XGE sub-interface view, MultiGE sub-interface view, 25GE sub-interface view, 40GE sub-interface view, 100GE sub-interface view, Eth-Trunk sub-interface view, VLANIF interface view, loopback interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

User hosts and Layer 3 multicast devices directly connected to user network segments must run IGMP. A multicast device can process IGMP messages sent from user hosts only after IGMP is enabled on the interfaces connected to user network segments.

Prerequisites

IP multicast routing has been enabled using the multicast routing-enable command.

If IGMPv1 is run on an interface, you must enable pim dm or pim sm. This is because IGMPv1 does not the querier election. In IGMPv1, the querier is specified by Protocol Independent Multicast (PIM).

If IGMPv2/v3 is run on an interface, pim dm or pim sm is recommended. Although IGMPv2/v3 supports the querier election, enabling PIM improves the system stability.

Precautions

If PIM and IGMP need to be enabled on the same interface, enable PIM, and then IGMP.
If IGMP parameters are configured on an interface, the parameter settings take effect only after IGMP is enabled.
Running the igmp enable command failed on the VLANIF interface because Layer 2 multicast querier or report-suppress is enabled for this VLAN.
If both Layer 2 and Layer 3 multicast services are required in a VLAN, enable IGMP on the corresponding VLANIF interface first, and then enable IGMP snooping in the VLAN. If IGMP snooping is enabled in the VLAN first, IGMP cannot be enabled on the VLANIF interface. In addition, the maximum number of Layer 3 multicast forwarding entries depends on the maximum number of Layer 2 multicast forwarding entries.

Example

# Enable IGMP on VLANIF100 connected to a user network segment.

<HUAWEI> system-view
[HUAWEI] multicast routing-enable
[HUAWEI] interface vlanif 100
[HUAWEI-Vlanif100] igmp enable

# Enable IGMP on GE0/0/1 connected to a user network segment.

<HUAWEI> system-view
[HUAWEI] multicast routing-enable
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] undo portswitch
[HUAWEI-GigabitEthernet0/0/1] igmp enable