Configuring Igmp Fast Leave Processing - H3C LS-3100-52P-OVS-H3 Operation Manual

To do...
Configure the other querier
present interval
If not statically configured, the startup query interval is 1/4 of the "IGMP query interval". By default,
the IGMP query interval is 60 seconds, so the startup query interval = 60 / 4 = 15 (seconds).
If not statically configured, the startup query count is set to the IGMP querier robustness variable.
By default, the IGMP querier robustness variable is 2, so the startup query count is also 2.
If not statically configured, the other querier present interval is [ IGMP query interval ] times [ IGMP
robustness variable ] plus [ maximum response time for IGMP general queries ] divided by two. The
default values of these three parameters are 60 (seconds), 2 and 10 (seconds) respectively, so the
other querier present interval = 60 × 2 + 10 / 2 = 125 (seconds).
If statically configured, the startup query interval, the startup query count, and the other querier
present interval take the configured values.
Make sure that the other querier present interval is greater than the IGMP query interval; otherwise
the IGMP querier may change frequently on the network.
Make sure that the IGMP query interval is greater than the maximum response time for IGMP
general queries; otherwise, multicast group members may 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 or
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.
Thus, the leave latency is reduced on one hand, and the network bandwidth is saved on the other hand.
Follow these steps to configure IGMP fast leave processing
To do...
Enter system view
Enter IGMP view
Use the command...
igmp timer
other-querier-present interval
Use the command...
system-view
igmp
1-15
Remarks
Optional
For the system default, see
"Note" below.
Remarks
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