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•
To avoid frequent IGMP querier changes, set the IGMP other querier present timer greater than
the IGMP general query interval. In addition, configure the same IGMP other querier present
timer for all IGMP routers on the same subnet.
•
To avoid mistakenly deleting multicast receivers, set the IGMP general query interval greater
than the maximum response time for IGMP general queries.
•
To speed up the response to IGMP queries and avoid simultaneous timer expirations that cause
IGMP report traffic bursts, set an appropriate maximum response time.
For IGMP general queries, the maximum response time is set by the
max-response-time
command.
For IGMP group-specific queries and IGMP group-and-source-specific queries, the
maximum response time equals the IGMP last member query interval.
•
The following configurations take effect only on the devices that run IGMPv2 and IGMPv3:
Maximum response time for IGMP general queries.
IGMP last member query interval.
IGMP last member query count.
IGMP other querier present interval.
Configuring the IGMP query and response parameters globally
Step
Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter IGMP view.
igmp
[
vpn-instance
vpn-instance-name
]
N/A
3.
Set the IGMP querier's
robustness variable.
robust-count count
By default, the IGMP querier's
robustness variable is 2.
4.
Set the IGMP startup query
interval.
startup-query-interval interval
By default, the IGMP startup
query interval equals one quarter
of the IGMP general query
interval.
5.
Set the IGMP startup query
count.
startup-query-count count
By default, the IGMP startup
query count equals the IGMP
querier's robustness variable.
6.
Set the IGMP general query
interval.
query-interval interval
By default, the IGMP general
query interval is 125 seconds.
7.
Set the IGMP last member
query interval.
last-member-query-interval
interval
By default, the IGMP last member
query interval is 1 second.
8.
Set the IGMP last member
query count.
last-member-query-count count
By default, the IGMP last member
query count equals the IGMP
querier's robustness variable.
9.
Set the maximum response
time for IGMP general
queries.
max-response-time time
By
default,
the
maximum
response time for IGMP general
queries is 10 seconds.
10.
Set the IGMP other querier
present timer.
other-querier-present-interval
interval
By default, the IGMP other querier
present timer is calculated by
using the following formula:
[ IGMP general query interval ] ×
[ IGMP robustness variable ] +
[ maximum response time for
IGMP general queries ] / 2.
