Users Guide

IGMP snooping dynamically detects the mrouter interface based on IGMP queries that it receives. If there are more than

one multicast routers connected to the snooping switch, one of them will send IGMP queries and the interface

connected to that router is dynamically learnt as an mrouter port. You must configure the interfaces connected to other

multicast routers as static mrouter port.

● (Optional) Configure the IGMP version using the ip igmp version version-number command in VLAN INTERFACE

mode.

● (Optional) The fast leave option allows the IGMP snooping switch to remove an interface from the multicast group

immediately on receiving the leave message. Enable fast leave with the ip igmp snooping fast-leave command in

VLAN INTERFACE mode.

● (Optional) Configure the time interval for sending IGMP general queries with the ip igmp snooping query-interval

query-interval-time command in VLAN INTERFACE mode.

● (Optional) Configure the maximum time for responding to a query advertised in IGMP queries using the ip igmp

snooping query-max-resp-time query-response-time command in VLAN INTERFACE mode.

● (Optional) Configures the time interval between group-specific IGMP query messages with the ip igmp snooping

last-member-query-interval query-interval-time command in VLAN INTERFACE mode.

IGMP snooping configuration

OS10(config)# ip igmp snooping enable

OS10(config)# interface vlan 100

OS10(conf-if-vl-100)# ip igmp snooping mrouter interface ethernet 1/1/32

OS10(conf-if-vl-100)# ip igmp snooping querier

OS10(conf-if-vl-100)# ip igmp version 3

OS10(conf-if-vl-100)# ip igmp snooping fast-leave

OS10(conf-if-vl-100)# ip igmp snooping query-interval 60

OS10(conf-if-vl-100)# ip igmp snooping query-max-resp-time 10

OS10(conf-if-vl-100)# ip igmp snooping last-member-query-interval 1000

View IGMP snooping information

OS10# show ip igmp snooping groups

Total Number of Groups: 480

IGMP Connected Group Membership

Group Address Interface Mode Expires

225.1.0.0 vlan3531 IGMPv2-Compat 00:01:35