Fortinet MR1 User Manual page 106

Vlan Database
set igmp fast-leave
This command enables or disables IGMP Snooping fast-leave admin mode on a selected
VLAN. Enabling fastleave allows the switch to immediately remove the layer 2 LAN interface,
participating in the VLAN, from its forwarding table entry upon receiving an IGMP leave
message for that multicast group without first sending out MAC-based general queries to the
interface. Fast-leave admin mode should be enabled only on VLANs where only one host is
connected to each layer 2 LAN port, to prevent the inadverdent dropping of the other hosts
that were connected to the same layer 2 LAN port but were still interested in receiving
multicast traffic directed to that group. Also, fast-leave processing is supported only with
IGMP version 2 hosts.
Syntax
set igmp fast-leave <1-3965>
no set igmp fast-leave <1-3965>
<1-3965> - VLAN ID (Range: 1 – 3965).
no - This command disables IGMP Snooping fast-leave admin mode on a selected
VLAN.
Default Setting
None
Command Mode
Vlan Database
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