H3C Technologies H3C S10500 Series Switches - Manual (Page 126)

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To do... Use the command... Remarks
Configure the IGMP general query
interval
igmp timer query interval
Required
60 seconds by default
Configure the maximum response
time for IGMP general queries
igmp max-response-time interval
Required
10 seconds by default
Configure the IGMP last-member
query interval igmp last-member-query-interval
interval Required
1 second by default
Configure the other querier present
interval
igmp timer other-querier-present
interval
Required
By default, the other querier
present interval is [ IGMP general
query interval ] × [ IGMP
robustness variable ] + [ maximum
response time for IGMP general
queries ] / 2.
CAUTION:
•
Make sure that the other querier present interval is greater than the IGMP general query interval.
Otherwise, the IGMP querier might change frequently on the network.
• Make sure that the IGMP general query interval is greater than the maximum response time for IGMP
general queries. Otherwise, multicast group members might be wrongly removed.
• The configurations of the maximum response time for IGMP general queries, the IGMP last-member
query interval and the IGMP other querier present interval are effective only for IGMPv2 and IGMPv3.
Configuring IGMP fast-leave processing
In some applications, such as ADSL dial-up networking, only one multicast receiver host is attached to a
port of the IGMP querier. To allow fast response to the leave messages of the host when it switches
frequently from one multicast group to another, you can enable IGMP fast-leave processing on the IGMP
querier.
With fast-leave processing enabled, after receiving an IGMP leave message from a host, the IGMP
querier directly sends a leave notification to the upstream without sending IGMP group-specific queries
or IGMP group-and-source-specific queries. Thus, the leave latency is reduced on one hand, and the
network bandwidth is saved on the other hand.
Configuring IGMP fast-leave processing globally
Follow these steps to configure IGMP fast-leave processing globally:
To do... Use the command... Remarks
Enter system view system-view —
Enter public network IGMP view or
VPN instance IGMP view igmp [ vpn-instance
vpn-instance-name ]
—
Configure IGMP fast-leave
processing fast-leave [ group-policy
acl-number ] Required
Disabled by default