Configuring Igmp Queries And Responses - HP A6600 Configuration Manual

To do...
3. Enable IGMP snooping
querier.
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 might affect IGMP querier
elections because it sends IGMP general queries with a low source IP address. For more information
about IGMP querier, see

Configuring IGMP queries and responses

You can tune the IGMP general query interval based on actual condition of the network.
After 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.
For IGMP general queries, you can configure the maximum response time to fill their Max Response
•
time field.
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
To do...
1. Enter system view.
2. Enter IGMP-snooping view.
3. Configure the maximum
response time to IGMP
general queries.
4. Configure the IGMP
last-member query interval.
Configuring IGMP queries and responses in a VLAN
To do...
1. Enter system view.
2. Enter VLAN view.
3. Configure IGMP general
query interval.
Use the command...
igmp-snooping querier
"Configuring IGMP."
Use the command...
system-view
igmp-snooping
max-response-time interval
last-member-query-interval interval
Use the command...
system-view
vlan vlan-id
igmp-snooping query-interval interval
24
Remarks
Required.
Disabled by default.
Remarks
—
—
Optional.
10 seconds by default.
Optional.
1 second by default.
Remarks
—
—
Optional.
60 seconds by default.