igmp-snooping version

Function

The igmp-snooping version command configures the version of IGMP messages that IGMP snooping can process in a VLAN.

The undo igmp-snooping version command restores the default IGMP message version.

By default, IGMP snooping can process IGMPv1 and IGMPv2 messages in a VLAN.

Format

igmp-snooping version version

undo igmp-snooping version

Parameters

Parameter	Description	Value
version	Specifies the version of IGMP messages that can be processed in a VLAN.	The value is an integer ranging from 1 to 3. 1: indicates that IGMP snooping processes only IGMPv1 messages. 2: indicates that IGMP snooping processes IGMPv1 and IGMPv2 messages. 3: indicates that IGMP snooping processes IGMPv1, IGMPv2, and IGMPv3 messages.

Views

VLAN view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

The IGMP protocol maintains group memberships between Layer 3 multicast devices and hosts. IGMP has three versions: v1, v2, and v3. This command specifies the version of IGMP messages that IGMP snooping can process. Generally, configure the same version on the Layer 2 device as that on the upstream Layer 3 multicast device. If IGMP is not enabled on the Layer 3 multicast device, configure the IGMP message version on the Layer 2 device to be later than or equal to the version running on downstream hosts.

When hosts in a VLAN run different IGMP versions, run the igmp-snooping version command to enable the Layer 2 device to process IGMP messages sent from all the hosts.

Prerequisites

IGMP snooping has been enabled globally using the igmp-snooping enable (system view) command.

Precautions

If IGMP snooping is disabled in the specified VLAN, the configuration succeeds but does not take effect until IGMP snooping is enabled in the VLAN. To enable IGMP snooping in a VLAN, run the igmp-snooping enable (VLAN view) command.

When the IGMP snooping version is set to IGMPv3:

The switch can use only the default Layer 2 multicast forwarding mode.
The S2720-EI, S5720-LI, S5720S-LI, S6720-LI, S6720S-LI, S5720-SI, S5720I-SI, S5720S-SI, S5730-SI, S5730S-EI, S6720-SI and S6720S-SI forward multicast data by looking up the forwarding table according to the VLAN ID and group address.

This command cannot be used in user VLANs of a multicast VLAN.

If the IGMP message version is changed from IGMPv3 to IGMPv2, the system deletes all the dynamic IGMP snooping entries when the aging time expires and processes static IGMP snooping entries as follows:

Does not delete static entries that have only multicast groups and no multicast sources.
Deletes the static entries that have both multicast groups and multicast sources. When the IGMP message version is restored to IGMPv3, the system restores these entries.

Example

# Set the version of the IGMP messages that can be processed by IGMP snooping to IGMPv1 in VLAN 2.

<HUAWEI> system-view
[HUAWEI] igmp-snooping enable
[HUAWEI] vlan 2
[HUAWEI-vlan2] igmp-snooping enable
[HUAWEI-vlan2] igmp-snooping version 1