Service Manual

Removing a Group-Port Association
To congure or view the remove a group-port association feature, use the following commands.
• Congure the switch to remove a group-port association after receiving an IGMP Leave message.
INTERFACE VLAN mode
ip igmp fast-leave
• View the conguration.
INTERFACE VLAN mode
show config
Example of Conguration Output After Removing a Group-Port Association
Dell(conf-if-vl-100)#show config
!
interface Vlan 100
no ip address
ip igmp snooping fast-leave
shutdown
Dell(conf-if-vl-100)#
Disabling Multicast Flooding
If the switch receives a multicast packet that has an IP address of a group it has not learned (unregistered frame), the switch oods
that packet out of all ports on the VLAN.
When you congure the no ip igmp snooping flood command, the system drops the packets immediately. The system does
not forward the frames on mrouter ports, even if they are present. Disable Layer 3 multicast (no ip multicast-routing) in
order to disable multicast ooding.
• Congure the switch to only forward unregistered packets to ports on a VLAN that are connected to mrouter ports.
CONFIGURATION mode
no ip igmp snooping flood
Specifying a Port as Connected to a Multicast Router
To statically specify or view a port in a VLAN, use the following commands.
• Statically specify a port in a VLAN as connected to a multicast router.
INTERFACE VLAN mode
ip igmp snooping mrouter
• View the ports that are connected to multicast routers.
EXEC Privilege mode.
show ip igmp snooping mrouter
Conguring the Switch as Querier
To congure the switch as a querier, use the following command.
Hosts that do not support unsolicited reporting wait for a general query before sending a membership report. When the multicast
source and receivers are in the same VLAN, multicast trac is not routed and so there is no querier. Congure the switch to be the
querier for a VLAN so that hosts send membership reports and the switch can generate a forwarding table by snooping.
• Congure the switch to be the querier for a VLAN by rst assigning an IP address to the VLAN interface.
INTERFACE VLAN mode
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Internet Group Management Protocol (IGMP)