Stopping snoopers from snooping non-IGMP messages > Controlling which addresses create All Groups entries

Configuring switches 1 and 3

The output of the command show igmpsnooping, above, shows that switch 2 is still receiving the multicast group 224.12.13.14 even though it has no ports interested in receiving it. This is because switch 2 still switches the OSPF Hello packet, which it received on port 24, to switch 3. Switch 3 receives this Hello packet on port 25, adds port 25 to its All Groups list and forwards the packet on to switch 1.

The best solution to this is to remove 224.0.0.5 from switch 3 and switch 1 as well, by using the following commands on each switch:

set igmpsnooping routermode=ip

delete igmpsnooping routeraddress=224.0.0.5

Adding other router addresses

If you want to specify that other addresses belong to routers, you can use the commands:

set igmpsnooping routermode=ip

add igmpsnooping routeraddress=ipadd

The ipadd must be of the form 224.0.0.x, and can be a comma-separated list of addresses.

The example below starts again with the default configuration, and first removes the OSPF router address, then adds another address—224.0.0.254—to illustrate use of the command.

Manager Switch 2> set igmpsnooping routerm=ip

Info (1005282): IGMPSnooping Routermode successfully updated.

Manager Switch 2> show igmpsnooping routeraddress

IGMP Snooping Router Address

----------------------------------------------------------------------

IGMP Snooping Router Mode

......... ip

 

Router Address

List

 

 

--------------------------------------------------------

224.0.0.1

224.0.0.4

224.0.0.6

224.0.0.13

224.0.0.2

224.0.0.5

224.0.0.9

224.0.0.15

----------------------------------------------------------------------

Manager Switch 2> del igmpsnooping routeraddress=224.0.0.5

Info (1005272): Multicast addresses successfully deleted.

Manager Switch 2> add igmpsnooping routeraddress=224.0.0.254

Info (1005275): Multicast addresses successfully added.

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Allied Telesis AR400 manual Configuring switches 1, Adding other router addresses, AlliedWare OS How To Note Igmp