Setting The Maximum Number Of Igmp Groups; Configuring The Igmp Throttling Action - Cisco WS-C3560-48PS-S Software Configuration Manual

Configuring IGMP Filtering and Throttling

Setting the Maximum Number of IGMP Groups

You can set the maximum number of IGMP groups that a Layer 2 interface can join by using the ip igmp
max-groups interface configuration command. Use the no form of this command to set the maximum
back to the default, which is no limit.
This restriction can be applied to Layer 2 ports only; you cannot set a maximum number of IGMP groups
on routed ports or SVIs. You also can use this command on a logical EtherChannel interface but cannot
use it on ports that belong to an EtherChannel port group.
Beginning in privileged EXEC mode, follow these steps to set the maximum number of IGMP groups in
the forwarding table:
Command
Step 1
configure terminal
Step 2 interface interface-id
Step 3 ip igmp max-groups number
Step 4 end
Step 5
show running-config interface
interface-id
Step 6
copy running-config startup-config
To remove the maximum group limitation and return to the default of no maximum, use the no ip igmp
max-groups interface configuration command.
This example shows how to limit to 25 the number of IGMP groups that a port can join.
Switch(config)# interface gigabitethernet0/2
Switch(config-if)# ip igmp max-groups 25
Switch(config-if)# end

Configuring the IGMP Throttling Action

After you set the maximum number of IGMP groups that a Layer 2 interface can join, you can configure
an interface to remove a randomly selected multicast entry in the forwarding table and to add the next
IGMP group to it by using the ip igmp max-groups action replace interface configuration command.
Use the no form of this command to return to the default, which is to drop the IGMP join report.
Follow these guidelines when configuring the IGMP throttling action:
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Catalyst 3560 Switch Software Configuration Guide
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This restriction can be applied to Layer 2 ports only; you can use this command on a logical
EtherChannel interface but cannot use it on ports that belong to an EtherChannel port group.
When the maximum group limitation is set to the default (no maximum), entering the ip igmp
max-groups action {deny | replace} command has no effect.
Purpose
Enter global configuration mode.
Enter interface configuration mode, and enter the interface to configure.
The interface can be a Layer 2 port that does not belong to an
EtherChannel group or a EtherChannel interface.
Set the maximum number of IGMP groups that the interface can join.
The range is from 0 to 4294967294. The default is to have no maximum
set.
Return to privileged EXEC mode.
Verify the configuration.
(Optional) Save your entries in the configuration file.
Chapter 19 Configuring IGMP Snooping and MVR
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