INTERFACE modeip igmp query-interval• Adjust the maximum response time.INTERFACE modeip igmp query-max-resp-time• Adjust the last member query interval.INTERFACE modeip igmp last-member-query-intervalAdjusting the IGMP Querier Timeout ValueIf there is more than one multicast router on a subnet, only one is elected to be the querier, which is therouter that sends queries to the subnet.1. Routers send queries to the all multicast systems address, 224.0.0.1. Initially, all routers send queries.2. When a router receives a query, it compares the IP address of the interface on which it was receivedwith the source IP address given in the query. If the receiving router IP address is greater than thesource address given in the query, the router stops sending queries. By this method, the router withthe lowest IP address on the subnet is elected querier and continues to send queries.3. If a specified amount of time elapses during which other routers on the subnet do not receive aquery, those routers assume that the querier is down and a new querier is elected.The amount of time that elapses before routers on a subnet assume that the querier is down is the otherquerier present interval.• Adjust the other querier present interval.INTERFACE modeip igmp querier-timeoutConfiguring a Static IGMP GroupTo configure and view a static IGMP group, use the following commands.Multicast traffic for static groups is always forwarded to the subnet even if there are no members in thegroup.Static groups have an expiration value of Never and a Last Reporter value of CLI, as shown in the examplein Viewing IGMP Groups.• Configure a static IGMP group.INTERFACE modeip igmp static-group• View the static groups.EXEC Privilege mode.show ip igmp groups302 Internet Group Management Protocol (IGMP)
