Ip Igmp Flood-Group - Allied Telesis IE220 Series Manual

IGMP IGMP S C
AND NOOPING OMMANDS
-
IP IGMP FLOOD GROUP

ip igmp flood-group

Overview Use this command to configure a static multicast group that will flood matching
packets to all ports in the VLAN and not mirror any packets matching that group to
the CPU.
Use the no variant of this command to remove an IGMP flooding group.
Syntax ip igmp flood-group <ip-address> [<vlan-id>]
no ip igmp flood-group <ip-address>
Default Not set.
Mode Interface Configuration
Usage notes Multicast packets from an unregistered source will be mirrored to the CPU to
ensure IGMP and PIM-SM knows about the group. In certain networks, it is possible
for a large number of packets with a number of different sources destined for the
same group address, to overwhelm a switches hardware table. This could cause
packets to be stuck mirrored to the CPU forever, resulting in high CPU usage and
in some cases stack failovers.
This command adds an all sources multicast entry into the switches multicast
hardware table, to flood multicast packets to all ports within the VLAN without
mirroring the traffic to CPU. This significantly reduces the number of hardware
entries consumed.
The Layer 3 variant of this command:
ip igmp flood-group <ip-address> <vlan-id>
is only supported on one VLAN group address. Any number of the Layer 2 variants
can be used.
Example To configure an IGMP flooding group to Layer 2 ports only, use the following
commands. This will flood any UDP packet to group 239.255.255.250 to all ports in
vlan1:
awplus#
awplus(config)#
awplus(config-if)#
C613-50644-01 Rev B
Parameter Description
<ip-address>
Standard IP Multicast group address, entered in the form A.B.C.D.
<vlan-id>
Layer 3 downstream interface list for Layer 3 forwarding of multicast
packets.
configure terminal
int vlan1
Command Reference for IE220 Series
AlliedWare Plus™ Operating System - Version 5.5.3-0.x
ip igmp flood-group 239.255.255.250
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