Allied Telesis AT-9000 Series - Manual (Page 430)

Chapter 23: Internet Group Management Protocol (IGMP) Snooping
402
Disabling IGMP Snooping
The command to disable IGMP Snooping on the switch is the NO IP IGMP
SNOOPING command in the Global Configuration mode. To disable
IGMP Snooping:
awplus> enable
awplus# configure terminal
awplus(config)# no ip igmp snooping
When IGMP Snooping is disabled, the switch floods the multicast packets
on all ports, except on ports that receive the packets.