Last Member Query Interval; Maximum Response Time; Fast-Leave Processing - Avaya 2330 Manual

members of a group on a VLAN. Use the following formula to calculate the group
membership timer interval value:
- Group membership timer interval = ((2 x query interval) + maximum response time)
• Other querier timer interval—The "other querier timer interval" is the amount of time that
must pass before which an IGMP Snooping module decides that there is no longer
another multicast router that should be the querier in a VLAN. When the IGMP Snooping
module stops receiving external queries on a VLAN, the module waits for the next query
for a period of time that equals the other querier timer interval. If the module does not
receive any query within this duration of time, the module assumes there is no other
querier present in the VLAN and removes the dynamically-learned mrouter port. If the
querier feature is enabled on the VLAN, the querier feature starts generating general
query packets to all the ports in the VLAN. Use the following formula to calculate the other
querier timer interval value:
- Other querier interval = ((2 x query interval) + (maximum response time)/2)
For example, if the query interval is set to 200 seconds (200000 milliseconds [ms]), and the
maximum response time is set to 10 seconds, then you can calculate the following:
• Group membership timer interval = ((2 x 200 seconds) + 10 seconds) = 410 seconds
• Other querier timer interval = ((2 x 200 seconds) + (10 seconds/2)) = 405 seconds

Last member query interval

The "last member query interval" is the maximum response time inserted into group-specific
queries sent in response to "leave group" messages, and is also the amount of time between
group-specific query messages. The range of values for the last member query interval is 1000
– 25500 ms. The default value is 1000 ms. The last member query interval value can be
configured to modify the "leave latency" of the network. A reduced value results in reduced
time to detect the loss of the last member of a group.

Maximum response time

The maximum response time is inserted into the periodic general queries sent by a querier.
You can control the burstiness of IGMP messages on the subnet by varying the maximum
response time. For example, larger values make the IGMP message traffic less bursty because
the host responses are spread out over a larger interval. The number of seconds for the
maximum response time must be less than the query Interval.

Fast-leave processing

You can configure the Secure Router 2330/4134 to perform fast-leave processing.
Configuration — Layer 2 Ethernet
IGMP Snooping
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