Allied Telesis AT-S62 - Manual (Page 186)

Chapter 16: IGMP Snooping
186 Section II: Advanced Operations
This parameter is useful with networks that contain a large number of
multicast groups. You can use the parameter to prevent the switch’s
MAC address table from filling up with multicast addresses, leaving no
room for dynamic or static MAC addresses. The range is 1 address to
2048 addresses. The default is 256 multicast addresses.
4. After setting the IGMP snooping parameters, click Apply.
A change to an IGMP parameter is immediately implemented on the
switch.
5. To permanently save the change, click the Save Config menu option.