Community discussions

 
tomabcd
just joined
Topic Author
Posts: 6
Joined: Wed Jan 25, 2017 6:17 pm

Multicast data seems to be going to all lan ports.

Wed Jan 25, 2017 7:09 pm

I have a Mikrotik router RB2011ViAS-IN that has port 1 setup for the Wan and all of the others as the LAN.
The router is setup to provide DHCP address out the lan ports.
I have a HDMI to IP encoder connected to port 4 setup to provide a 3 Mb Multicast IP video stream.
I have 2 PCs connected to ports 3 and 8.
I login to the router and clicked on the interfaces button and can see the network traffic on each interface.

On ether4 (encoder) it is showing around 3Mb RX
On ether3 & ether8 (PCs) it is showing around 3Mb Tx.
My problem is neither PC is connected to the Multicast stream. So it seems the router is just blasting the data to everyone regardless if they want the stream or not.

Is this expected? Is there some setting in the router so the stream is only sent to PCs that request it?

I ran an app (igmpquery) and it did NOT show any igmp connection between the PCs and the streaming source.
If I started a stream on a PC then igmp did show a connection from the streaming source to the PC.

Thanks
Tom
 
andriys
Forum Guru
Forum Guru
Posts: 1180
Joined: Thu Nov 24, 2011 1:59 pm
Location: Kharkiv, Ukraine

Re: Multicast data seems to be going to all lan ports.

Wed Jan 25, 2017 7:29 pm

Is this expected? Is there some setting in the router so the stream is only sent to PCs that request it?
Here's a short answer. Yes, it is expected. And no, there's nothing you can do about it right now. A somewhat longer answer follows.

There are means (PIM, IGMP proxy) in RouterOS to manage multicast traffic on L3 (i.e. when doing routing). However RouterOS has nothing to offer to deal with multicast traffic on L2 (i.e. when doing switching), no matter if your are switching in hardware or via a software bridge. If one port in switching group or bridge sends or receives multicast traffic, this traffic is always unconditionally broadcasted via the rest of the ports in the group. You can search the forum to see that IGMP snooping support has already been requested multiple times here, so please do not post yet another feature request. :) There's no ETA, it's not even clear if this feature is ever implemented at all.
 
tomabcd
just joined
Topic Author
Posts: 6
Joined: Wed Jan 25, 2017 6:17 pm

Re: Multicast data seems to be going to all lan ports.

Wed Jan 25, 2017 8:43 pm

Ok, so multicast is only blocked/controlled when routing, so can I setup the unit so that I am routing between all of the ports and then setup the routing to allow the IGMP proxy stuff through?

Port 1 - wan
Port 2 - Encoder
Port 3 - 10

So this would mean the Port 3 would need to be bridged to Port 2 and another bridge to port 1. (I think)

I realize that this will be a performance hit.
 
andriys
Forum Guru
Forum Guru
Posts: 1180
Joined: Thu Nov 24, 2011 1:59 pm
Location: Kharkiv, Ukraine

Re: Multicast data seems to be going to all lan ports.

Wed Jan 25, 2017 9:01 pm

can I setup the unit so that I am routing between all of the ports and then setup the routing to allow the IGMP proxy stuff through?
Yes, you can.
Port 1 - wan
Port 2 - Encoder
Port 3 - 10

So this would mean the Port 3 would need to be bridged to Port 2 and another bridge to port 1.
No. Bridging is essentially the same as switching, but done in software. And you need routing.

Where this encoder should stream to?
 
w0lt
Member
Member
Posts: 484
Joined: Wed Apr 02, 2008 2:12 pm
Location: Minnesota USA

Re: Multicast data seems to be going to all lan ports.

Thu Jan 26, 2017 1:21 am

We need IGMP Snooping!! :(
MTCNA - 2011

" The Bitterness of Poor Quality Remains Long After the Sweetness of Low Price is Forgotten "

Image
 
lpt2007
Frequent Visitor
Frequent Visitor
Posts: 67
Joined: Wed Jul 23, 2014 4:08 pm

Re: Multicast data seems to be going to all lan ports.

Sun Nov 25, 2018 7:28 pm

Anybody solve this problem?

I installed multicast and enable snooping in bridge, but not working.

https://wiki.mikrotik.com/wiki/Manual:I ... P_Snooping

command:
interface bridge mdb print

show nothing, still multicasting on all ports in bridge at the same time
Last edited by lpt2007 on Sun Nov 25, 2018 9:17 pm, edited 1 time in total.
 
eftomi
just joined
Posts: 23
Joined: Wed Jan 25, 2017 6:29 pm

Re: Multicast data seems to be going to all lan ports.

Sun Nov 25, 2018 7:45 pm

 
lpt2007
Frequent Visitor
Frequent Visitor
Posts: 67
Joined: Wed Jul 23, 2014 4:08 pm

Re: Multicast data seems to be going to all lan ports.

Sun Nov 25, 2018 9:49 pm

Who is online

Users browsing this forum: No registered users and 28 guests