IGMP mac on bridge port

RouterOS Wireless Networking
1

Hello everybody,

I have the folowing setup:

(2 microsoft tmg using network load balacing in igmp mode) → mikrotik 411ah with ROS5.19 → laptops.

The nlb, using igmp mode, has a mac address starting with 01:00:…

The mikrotik device doenst seem to learn this address in the wireless bridge, and so it copies each packet from laptop to nlb mac to each wireless client.

If i have 2 laptops registered on the mikrotik device, from laptop1 i can see traffic going to the nlb mac on laptop2.

On all other swithes i have in my network i’ve enabled igmp snooping and it seems to work properly. It found the nlb mac igmp group and it’s forwarding packets only on the groups ports.

How can i achieve a similar behavior with mikrotik? sending all internet traffic to all wireless clients is a killer.

Thanks.

2

I´m on deep water after 14 hours of networking today, i anyone else see that this is completely wrong, please correct me.

Do you have and “admin mac” on your bridge, if i remember correctly that is something you have to keep in mind in this senario.

3

RouterOS does not support snooping as that generally brakes multicast.

What you can do is install IGMP-proxy on dedvices and use tunnels to forward multicast packets and in the end, wirelss will broadcast the stream into the air as an AP.

Bridge will forward multicast packets as described in RFC.

4

The bridge should be able to learn that a multicast mac is on a specific port, or at least i should be able to ‘touch’ multicast traffic.

as i understand from the packet flow diagrams, the multicast mac packet is copied to all bridge ports automatically.

5

yes, that is the behaviour. Actually, packet is copied to all ports except ingress port as per RFC.

If you have bridged environment better use tunnels and route multicast traffic over the tunnels.

6

ok, some links would help :slight_smile: