igmp-snooping max-response-time

Function

The igmp-snooping max-response-time command sets the maximum time for a downstream host to respond to a querier.

The undo igmp-snooping max-response-time command restores the default setting.

By default, the maximum time for a downstream host to respond to a querier is 10s.

Format

igmp-snooping max-response-time max-response-time

undo igmp-snooping max-response-time

Parameters

Parameter	Description	Value
max-response-time	Specifies the maximum time for a downstream host to respond to a querier.	The value ranges from 1 to 25.

Parameter

Description

Value

max-response-time

Specifies the maximum time for a downstream host to respond to a querier.

The value ranges from 1 to 25.

Views

VLAN view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
l2mc	write

Usage Guidelines

Usage Scenario

The igmp-snooping max-response-time command has the following functions:

Sets the maximum response time to control the deadline for hosts to send IGMP Report messages.If the querier function is enabled, set a short maximum response time to enable hosts to rapidly respond to IGMP Query messages, and set a long maximum response time to prevent traffic congestion caused by too many Report or Leave messages sent by hosts on a network.
Check that the interval at which IGMP general query messages are sent is greater than the maximum response time for a downstream host to respond to the querier; otherwise, multicast group members may be deleted mistakenly.
Changes the aging time of member ports.After receiving a Report message from a downstream device, a device sets the aging time of the corresponding member port based on the following formula: Aging time of a member port = Number of times group-specific query messages are sent x Interval at which general query messages are sent + Maximum time for a downstream host to respond to a querier. The default aging time is 130260s. The maximum time for a downstream host to respond to a querier is set using the igmp-snooping max-response-time command. The number of times group-specific group query messages are sent is set using the igmp-snooping robust-count command. The interval at which general query messages are sent is set using the igmp-snooping query-interval command.

Prerequisites

IGMP snooping has been configured using the igmp-snooping enable command.

Configuration Impact

If the igmp-snooping max-response-time command is run in the same view several times, the latest configuration overrides the previous one.

Precautions

When the igmp-snooping max-response-time command is used to set the aging time of member ports, the settings of parameters in this command must be consistent on a Layer 2 device and its upstream Layer 3 device; otherwise, multicast data transmission between Layer 2 and Layer 3 networks will be interrupted.

The maximum time for a downstream host to respond to a querier fails to be set in a VLAN when a Dot1q termination sub-interface has been added to the VLAN.

Example

# Set the maximum time for a downstream host to respond to a querier to 20s in VSI 10.

<HUAWEI> system-view
[~HUAWEI] igmp-snooping enable
[*HUAWEI] vlan 10
[*HUAWEI-vlan10] igmp-snooping max-response-time 20