igmp-snooping report-suppress (Traffic profile view)

Function

The igmp-snooping report-suppress command enables suppression of IGMP Report and Leave message in a traffic profile.

The undo igmp-snooping report-suppress command cancels configuration of IGMP Report and Leave message suppression in a traffic profile.

By default, IGMP Report and Leave message suppression is disabled in a traffic profile.

Format

igmp-snooping report-suppress

undo igmp-snooping report-suppress

Parameters

None

Views

Traffic profile view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

When a Layer 2 device receives an IGMP Membership Report message (Report or Leave message) from a group member, the Layer 2 device forwards the message to the directly connected Layer 3 device. A group member host sends a Membership Report message in the following situations:

When joining a multicast group, a host sends a Report message. When a multicast group has multiple members in a VLAN, the Layer 3 device receives duplicate Report messages from the member hosts.
When receiving an IGMP General Query message, a host sends a Report message. Hosts use a timer to suppress duplicate Report messages in the same network segment. However, if the timer values on hosts are the same, the Layer 3 device can still receive duplicate Report messages.
A host running IGMPv2 or IGMPv3 sends a Leave message when leaving a multicast group. When a multicast group has multiple members in a VLAN, the Layer 3 device receives duplicate Leave messages from the member hosts.

After this function is configured, a Layer 2 device forwards only one IGMP Membership Report message to the upstream device in the following scenarios: When the first member joins a multicast group or a host sends a Report message in response to an IGMP Query message, the Layer 2 device forwards a Report message to the upstream device. The upstream device then creates or maintains the matching forwarding entry based on the Report message. When the last member of a group leaves the group, the Layer 2 device forwards a Leave message to the upstream device. The upstream device then deletes the matching forwarding entry. This reduces the number of IGMP messages on the network.

Prerequisites

IGMP snooping has been enabled using the igmp-snooping enable (traffic profile view) command.

Example

# Enable suppression of IGMP Report and Leave messages in traffic profile p1.

<HUAWEI> system-view
[HUAWEI] wlan
[HUAWEI-wlan-view] traffic-profile name p1
[HUAWEI-wlan-traffic-prof-p1] igmp-snooping enable
[HUAWEI-wlan-traffic-prof-p1] igmp-snooping report-suppress