mld-snooping last-listener-query-interval

Function

The mld-snooping last-listener-query-interval command sets the last listener query interval, that is, the interval at which Multicast-Address-Specific Query messages are sent in MLD snooping.

The undo mld-snooping last-listener-query-interval command restores the default interval.

By default, the last listener query interval is 1 second.

Format

mld-snooping last-listener-query-interval query-interval

undo mld-snooping last-listener-query-interval

Parameters

Parameter	Description	Value
query-interval	Specifies interval at which Multicast-Address-Specific Query messages are sent.	The value ranges from 1 to 5, in seconds.

Views

VLAN view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

By configuring the last listener query interval, you can:

Adjust the interval at which the querier sends Multicast-Address-Specific Query messages.

When MLD snooping querier is enabled, you can use the mld-snooping last-listener-query-interval command to set the interval at which the querier sends Multicast-Address-Specific Query messages.
Change the aging time of member ports.

When a Layer 2 device receives an MLD Done message from a host, it starts an aging timer for the corresponding member port. The aging time is calculated using the following formula: Aging time = Last listener query interval x Last listener query count. This command sets the last listener query interval in the formula. The last listener query count is set by the mld-snooping robust-count command.

If the querier receives Report messages from other hosts within the aging time, it continues to maintain the memberships of the multicast group. If the querier does not receive any Report messages within the aging time, it stops maintaining memberships of the multicast group.

Prerequisites

MLD snooping has been enabled globally using the mld-snooping enable command.

Precautions

The querier sets the maximum response time field in the Multicast-Address-Specific Query messages to the configured last listener query interval. Therefore, the maximum response time for Multicast-Address-Specific Query messages is the same as the interval at which Multicast-Address-Specific Query messages are sent.

The configuration takes effect only when both the following conditions are met:

MLD snooping is enabled in the VLAN using the mld-snooping enable command.
The local device is enabled to send Query messages using the mld-snooping querier enable or mld-snooping proxy command.

Example

# Set the last listener query interval to 2 seconds in VLAN 4.

<HUAWEI> system-view
[HUAWEI] mld-snooping enable
[HUAWEI] vlan 4
[HUAWEI-vlan4] mld-snooping enable
[HUAWEI-vlan4] mld-snooping last-listener-query-interval 2