Problem with Multicast with two RB on the same network

RouterOS General
1

Hi all,
i think i have a problem with ASM configuration in my network.
I have two RB493G running in my network, and each one has a multicast sources sending packets on their local lan interfaces.
When only one RB is running, everything works ok, and the multicast stream flows from local subnet to wan network after a join request from clients.
When both RB are running, it seems that casually one RB causes the stop of the multicast flow of the other one…

Every multicast source send packets to same multicast group (239.0.0.20, port 1200), so i guess it’s a problem related to the implementation of ASM multicast.
I need that every RB continues to send packets to that group even if are other RB in the network that are already sending to that group.
the clients needs to receive all packets forwarded to that group, regardless of senders.
I can’t find the right option to set under PIM configuration on RB.

I have this configuration on both routerboards:

I just added eth1 and eth2 to pim interface menu, no RP


Any help would be appreciated.
Thank You.

2

after some tests, i noticed that the problem is related to the coexistence of both router configured with pim multicast…
with only one router i have no problem, when i turn on the second one, it seems it blocks multicast packets delivered from the first one, but the behavior is not so deterministc.
This happens with same multicast groups and also between different multicast groups.
Maybe it is related to some “designated router” mechanism ?

3

I’m really confused..
It seems to work sometimes only if i set one router with pim and the other one with igmp-proxy…
If i set both routers with same multicast options, multicast streams stop to be delivered from at leat one router..
rellay can’t figure out why …
Any suggestions please ?