Why One Server Can get the multicast

[MrBeginner]

Hi,

I would like to ask about multicast.

I have two clients to get the video stream from video server. 

Our clients are connected to L2 switch. This switch connect to our customer switches.Customer switch connected to their network and video streaming server. This  streaming server is using multicast.

I enable igmp snooping in my l2 switch. But one of our client can get the multicast traffic but other client cannot get the multicast.

• So let me know server side can filter the who can only join to their multicast group ?
• Do i need to do some configuration in our layer 2 switch ?
• How can monitor the multicast traffic on my switch ?
• Can search the multicast domain IP ?

[paul driver]

Hello

If the server and hosts on the same subnet then no need to route MC, IGMP will do the job, however if one of the two hosts are on different switches than the source then this other host maybe not be able to receive the igmp query from the source and as such no MC traffic, In this case enable on this other switch enable ip igmp snooping querier this should then allow the other host to begin receiving MC traffic.
However to have MC over multiple subnets (vlans) then your need pim on the L3 interfaces to route the MC

[Giuseppe Larosa]

Hello @MrBeginner ,

>> I enable igmp snooping in my l2 switch. But one of our client can get the multicast traffic but other client cannot get the multicast.

to be able to receive the stream when IGMP snooping is active the client has to answer to IGMP General Queries with IGMP report, in some cases some receivers do not support IGMP.

So check using a SPAN session if the client that does not receive the stream is sending IGMP reports or not.

Edit:

as noted by @paul driver if the clients are in different VLANs you will need a full PIM multicast routing configuration all of the above considerations are valid if the clients and the source are in the same L2 VLAN.

Hope to help

Giuseppe

[MrBeginner]

Hi @Giuseppe Larosa  and @paul driver  ,

Server and client are different VLAN. our two client are same switch and same vlan. switch is connected to their L3 switch using access port.I don't have permission to access their L3 switch.

Do you mean if server and client are different vlan , do i need to do some configuration on my L2 switch ?

Even though our client are same vlan,do i need to do configuration on my l2 switch ?

Can Multicast filter one client only to access to server ? 

[paul driver]

Hello

Yes MC can be filtered for a particular host/network.

Now If your MC source is on a different vlan(subnet) then your receiving hosts then mc routing needs to be residing in this particular instance on the L3 switch unless you proxy igmp.is being used and as you don't have access to that L3 switch then I am assuming MC routing is indeed applied their for one of your hosts to be able to receive MC traffic.

[MrBeginner]

Hi @paul driver ,

let me know how do i know that MC routing is indeed applied their for one of your hosts to be able to receive MC traffic ? 

OR can i proof that MC routing is indeed applied their for one of your hosts to be able to receive MC traffic?