mld-snooping query-interval
Function
The mld-snooping query-interval command sets the general query interval in a VLAN, that is, the interval at which MLD General Query messages are sent in the VLAN.
The undo mld-snooping query-interval command restores the default general query interval in a VLAN.
By default, MLD General Query messages are sent at an interval of 125 seconds.
Parameters
Parameter |
Description |
Value |
|---|---|---|
query-interval |
Specifies the interval at which General Query messages are sent. |
The value is an integer that ranges from 10 to 65535, in seconds. |
Usage Guidelines
Usage Scenario
By setting the MLD general query interval, you can:
Specify the interval at which the querier sends MLD General Query messages.
When the querier function is enabled in a VLAN, you can use this command to set the general query interval. Then the querier sends General Query messages at the configured interval to maintain group memberships. The querier is more sensitive when it sends General Query messages at a smaller interval, but more bandwidth and resources are consumed.
Change the aging time of member ports.
When receiving an MLD Report message from a host, the switch starts the aging timer for the corresponding member port. The aging time is calculated using the following formula: Aging time = General query count x General query interval + Maximum response time for General Query messages. The mld-snooping query-interval command sets the general query interval. The general query count is set by the mld-snooping robust-count command, and the maximum response time for General Query messages is set by the mld-snooping max-response-time command.
The default general query interval defined in RFC documents is 125 seconds, but some vendors define their own default general query intervals. It is recommended that all devices on a multicast network use the same general query intervals (including MLD and MLD snooping general query intervals). On Huawei fixed switches, the default values of the MLD general query interval and MLD snooping general query interval are both 125 seconds.
Prerequisites
MLD snooping has been enabled globally using the mld-snooping enable command.
Precautions
The configuration takes effect only after you run the mld-snooping_enable command to enable MLD snooping in the VLAN.
Use this command only when the switch can send MLD Query message. The switch can send MLD Query messages only when MLD snooping proxy is enabled using the mld-snooping proxy command, or MLD snooping querier is enabled using the mld-snooping querier enable command.
The interval at which General Query messages are sent must be longer than the maximum response time for General Query messages. Otherwise, the switch will delete multicast memberships that should not be deleted.