mld-snooping suppression-time

Function

The mld-snooping suppression-time command sets the MLD message suppression time.

The undo mld-snooping suppression-time command restores the default MLD message suppression time.

By default, the MLD message suppression time is 10 seconds.

Format

mld-snooping suppression-time suppression-time

undo mld-snooping suppression-time

Parameters

Parameter	Description	Value
suppression-time	Specifies the MLD message suppression time.	The value is an integer ranging from 0 to 300, in seconds. The value 0 indicates that MLD messages are not suppressed.

Views

system view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

To protect an upstream Layer 3 device from attacks and reduce the load on the Layer 3 device, a Layer 2 device can suppress duplicate MLD Report messages. The default MLD message suppression time is 10 seconds. You can change the MLD message suppression time using the mld-snooping suppression-time command.

After you set the MLD message suppression time on a Layer 2 multicast device, the device acts as follows:

After the Layer 2 device receives an MLD Report message, it does not forward identical MLD Report messages to the router port within the suppression time.
If the Layer 2 device receives an MLD General Query message or Multicast-Address-Specific Query message within the suppression time, it does not suppress the first MLD Report message sent in response to the Query message. In addition, the Layer 2 device resets the suppression timer when it receives the first MLD Report message.

Prerequisites

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

Precautions

You can run this command for MLDv1 Done and MLDv2 packets, but the command does not take effect.

Example

# Set the MLD message suppression time to 15 seconds.

<HUAWEI> system-view
[HUAWEI] mld-snooping enable
[HUAWEI] mld-snooping suppression-time 15