Hi,

- Enable IGMP snooping querier (if there is no IGMP querier in the VLAN) on the device, closest to the multicast source
- Enable IGMP snooping on all switches between multicast source and listeners
- Set statically multicast Router ports on all switches to point to the multicast source
- Enable " igmp-snooping drop-unknown" feature, as by default IGMP snooping will regulate only known streams, e.g. groups for which it saw a pair of IGMP query-IGMP report. 

Flood restrict enables the switch to forward unknown multicast packets to a multicast router. For it to be effective on the VLAN, IGMP and MLD snooping must be enabled on the VLAN. Select L2 Multicast. Select the Add selected VLANs to MLD configuration option for the same VLANs to be configured for MLD snooping.

Addition: Based on the bullet point in Layer 2 network within the IGMP snooping topic. https://www.dell.com/support/manuals/en-cr/dell-emc-smartfabric-os10/smartfabric-os-user-guide-10-5-0/igmp-snooping?guid=guid-cc40ea60-4832-4245-865d-8c7a14e14cba&lang=en-us

• In a network, the snooping switch is connected to a multicast Router that sends IGMP queries. On a Layer 2 network that does not have a multicast router, you can configure the snooping switch to act as querier. Use the ip igmp snooping querier command in VLAN INTERFACE mode to send the queries.

Since we do have a multicast router, therefore, the "ip igmp querier" command is not needed. 

Young,

When there is a mrouter port, no igmp querier should be needed because the upstream router connected to the mrouter port will send the query to downstream receivers. But i saw another implementation guide also shows igmp querier is needed.

https://www.dell.com/support/kbdoc/en-my/000143003/l2-multicast-traffic-is-flooded-in-the-vlan-with-no-recievers

Can anyone confirm if the command "igmp querier" is needed, please? Thank you.