Internet Group Management Protocol (IGMP) manages multicast group members and runs on the network segments where Layer 3 multicast devices connect to user hosts. IGMP has three protocol versions: V1, V2, and V3. You can specify the IGMP snooping version on a Layer 2 device to enable it to process IGMP messages of specified versions. Generally, the IGMP snooping version on a Layer 2 device should be the same as the IGMP version used on the Layer 3 multicast device. If IGMP is disabled on the Layer 3 multicast device, set the IGMP snooping version to be the same as or later than the IGMP version running on user hosts.
Devices in the same virtual switching instance (VSI) must run the same IGMP version. When hosts in a VSI run different IGMP versions, configure an appropriate IGMP snooping version to ensure that the Layer 2 device to process IGMP messages from all the hosts.