H3C S7500E Series Ethernet Switches Operation Manual

Operation Manual – Multicast
H3C S7500E Series Ethernet Switches Chapter 4 IGMP Configuration
4-12
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
expires 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 the IGMP last member query interval.
When multiple multicast routers exist on the same subnet, the IGMP querier is
responsible for sending IGMP queries. If a non-querier router receives no IGMP query
from the querier within the “other querier present interval”, it will assume the querier to
have expired and a new querier election process is launched; otherwise, the
non-querier router will reset its “other querier present timer”.
I. Configuring IGMP query and response parameters globally
Follow these steps to configure IGMP query and response parameters globally:
To do... Use the command... Remarks
Enter system view
system-view
—
Enter IGMP view
igmp
—
Configure the IGMP query
interval
timer query interval
Optional
60 seconds by default
Configure the IGMP
querier robustness
variable
robust-count
robust-value
Optional
2 by default
Configure the maximum
response time for IGMP
general queries
max-response-time
interval
Optional
10 seconds by default
Configure the IGMP last
member query interval
Last-member-query-inte
rval interval
Optional
1 second by default
Configure the other
querier present interval
timer
other-querier-present
interval
Optional
For the system default,
see “Note” below.
II. Configuring IGMP query and response parameters on an interface
Follow these steps to configure IGMP query and response parameters on an interface: