Usage Scenario
The mld-snooping query-interval command provides the following functions:
- Sets an interval at which the querier sends general Query messages.
After the querier function is enabled and an interval is set using the mld-snooping query-interval command, the querier sends general Query messages at the configured interval to maintain group member information. The shorter the interval is, the more sensitive the device is and the more bandwidth and system resources are occupied.
The interval for the querier to send general Query messages must be greater than the maximum time for the querier to wait for responses from hosts. Otherwise, multicast group members may be deleted incorrectly.
- Adjusts the aging time of member interfaces.
After receiving a Report message from a downstream host, the device sets the aging time of the member interface using the following formula: Member interface aging time = Number of group-specific Query messages to be sent x Interval at which general Query messages are sent + Maximum time for the querier to wait for responses from downstream hosts. By default, the device sets the aging time to 130s. Run the mld-snooping query-interval command to set an interval at which general Query messages are sent, run the mld-snooping robust-count command to set the number of group-specific Query messages to be sent, and run the mld-snooping max-response-time command to set the maximum time that the querier waits for responses from downstream hosts.
Prerequisites
MLD snooping has been enabled using the mld-snooping enable command.
Configuration Impact
If the mld-snooping query-interval command is run more than once in the same view, the latest configuration overwrites the previous one.
Precautions
To use the mld-snooping query-interval configuration as a factor of adjusting the member interface aging time, set the same interval as that specified on its upstream device. Otherwise, multicast data transmission will be interrupted between the Layer 2 and Layer 3 devices.
The mld-snooping query-interval command fails to be run in a VSI view in the following condition:
- The VSI is bound to a BD.