H3C Technologies H3C S12500 Series Switches - Manual (Page 41)

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Step Command Remarks
1. Enter system view. system-view N/A
2. Enter VLAN view. vlan vlan-id N/A
3. Enable IGMP snooping
querier.
igmp-snooping querier Disabled by default.
Configuring parameters for IGMP queries and responses
CAUTION:
In the configuration, make sure that the IGMP general query interval is larger than the maximum response
delay for IGMP general queries. Otherwise, multicast group members might be deleted by mistake.
You can modify the IGMP general query interval based on actual condition of the network.
A multicast listening host starts a timer for each multicast group that it has joined when it receives an
IGMP query (general query or group-specific query). This timer is initialized to a random value in the
range of 0 to the maximum response delay advertised in the IGMP query message. When the timer value
decreases to 0, the host sends an IGMP report to the multicast group.
To speed up the response of hosts to IGMP queries and avoid simultaneous timer expirations causing
IGMP report traffic bursts, you must correctly set the maximum response delay.
• The maximum response delay for IGMP general queries is set by the max-response-time command.
• The maximum response delay for IGMP group-specific queries equals the IGMP last-member query
interval.
Configuring the global parameters for IGMP queries and responses
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter IGMP-snooping view. igmp-snooping N/A
3. Set the maximum response
delay for IGMP general
queries.
max-response-time interval 10 seconds by default.
4. Set the IGMP last-member
query interval.
last-member-query-interval interval 1 second by default.
Configuring the parameters for IGMP queries and responses in a VLAN
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter VLAN view. vlan vlan-id N/A
3. Configure IGMP general
query interval.
igmp-snooping query-interval interval 60 seconds by default.
4. Set the interval for sending
IGMP general queries.
igmp-snooping max-response-time interval 10 seconds by default.