igmp-snooping send-query enable

Function

The igmp-snooping send-query enable command configures a device to send IGMP Query messages that are used to respond to network topology changes to non-router ports.

The undo igmp-snooping send-query enable command restores the default configuration.

By default, a device is disabled from sending IGMP Query messages that are used to respond to network topology changes to non-router ports.

Format

igmp-snooping send-query enable

undo igmp-snooping send-query enable

Parameters

None

Views

System view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2mc	write

Usage Guidelines

Usage Scenario

If a link topology changes, devices will receive a link change event. Normally, these devices do not send IGMP general query messages. The link topology change, however, causes a ring network protocol to recalculate paths. As a result, multicast data cannot be switched to the new path in time. The igmp-snooping send-query enable command can be used to address this problem. This command enables a device to resend IGMP general Query messages after receiving a link change, update port information, and rapidly switch multicast data to the new forwarding path. This ensures uninterrupted multicast services. Updating port information involves the following operations:

Updating router ports: In MSTP networking, IGMP general query messages are sent to all non-router ports.
Updating member ports: After receiving IGMP General Query messages, hosts that remain as multicast members reply with IGMP Report messages and update information about member ports.

Prerequisites

IGMP snooping has been enabled globally and a ring network protocol has been configured.

Follow-up Procedure

The igmp-snooping send-query enable command is used on ring networks. After this command is run on a device on a ring network, the device will send IGMP Query messages with the source IP address of 192.168.0.1 when the topology changes. The source address can be changed using the igmp-snooping send-query source-address command.

Example

# Configure a device to send IGMP Query messages that are used to respond to network topology changes to non-router ports.

<HUAWEI> system-view
[~HUAWEI] igmp-snooping enable
[*HUAWEI] igmp-snooping send-query enable