H3C Technologies H3C S7500E Series Switches - Manual (Page 48)

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Follow these steps to enable IGMP snooping querier:
To do... Use the command... Remarks
Enter system view system-view —
Enter VLAN view vlan vlan-id —
Enable IGMP snooping querier igmp-snooping querier
Required
Disabled by default
It is meaningless to configure an IGMP snooping querier in a multicast network running IGMP.
Although an IGMP snooping querier does not take part in IGMP querier elections, it may affect
IGMP querier elections because it sends IGMP general queries with a low source IP address.
For details about IGMP querier, see IGMP Configuration of the IP Multicast Configuration
Guide.
Configuring IGMP Queries and Responses
You can tune the IGMP general query interval based on actual condition of the network.
Upon receiving an IGMP query (general query or group-specific query), a host starts a timer for
each multicast group it has joined. This timer is initialized to a random value in the range of 0 to
the maximum response time (the host obtains the value of the maximum response time from the
Max Response Time field in the IGMP query it received). When the timer value comes down to
0, the host sends an IGMP report to the corresponding multicast group.
An appropriate setting of the maximum response time for IGMP queries allows hosts to respond
to queries quickly and avoids bursts of IGMP traffic on the network caused by reports
simultaneously sent by a large number of hosts when the corresponding timers expire
simultaneously.
z For IGMP general queries, you can configure the maximum response time to fill their Max
Response time field.
z For IGMP group-specific queries, you can configure the IGMP last-member query interval
to fill their Max Response time field. Namely, for IGMP group-specific queries, the
maximum response time equals to the IGMP last-member query interval.
Configuring IGMP queries and responses globally
Follow these steps to configure IGMP queries and responses globally:
To do... Use the command... Remarks
Enter system view system-view —
Enter IGMP snooping view igmp-snooping —