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Blocking all IGMP traffic


I?m hoping someone may have the answer to this. I am trying to block ALL types of IGMP traffic on a particular interface on at 3560-24-TS-S.

We have a Summit 5i switch acting as a core switch for 400 users which all (VLAN 3) participate in a multicast group sourced from one of the servers on the same VLAN 3. All the equipment is managed via VLAN 3. From this Summit 5i core switch we have an untagged hand off to a Cisco 3560 - 24-TS-S which also has 400 DIFFERENT users participating in a multicast group sourced from a server physically connected to this Cisco switch but on VLAN 6. All equipment on this switch is also managed via VLAN 3. The problem I believe is that this handoff between the Summit 5i and the Cisco 3560 are having IGMP querying conflicts and it?s causing multicast troubles on both VLAN 3 and VLAN 6. I did setup the port as protected, blocked "unknown" unicast, multicast traffic and issued a no IP IGMP snooping vlan 3. But still having troubles.

I am using IGMP v2 and source filtering is not available until v3 so I am not sure how to block ALL IGMP traffic to try and help isolate this as 2 separate networks but still being managed on the same.

Any help is greatly appreciated...




Re: Blocking all IGMP traffic


This might be what you are looking for:

sw3456(config-if)#ip multicast boundary ?

<1-99> Access-list number

<1300-1999> (expanded range)

WORD IP Named Standard Access list



Re: Blocking all IGMP traffic

You can try this and control the IGMP queries on a given interface.

To disable groups on an interface, use the no ip igmp access-group interface configuration command.

This example shows how to configure hosts attached to a port as able to join only group

Switch(config)# access-list 1

Switch(config-if)# interface gigabitethernet0/1

Switch(config-if)# ip igmp access-group 1