Enable Multicast communication (Cisco Routers, Switches, Firewalls)

[Mohammed Shoukat Ali]

Dear Experts,

I wan to enable multicast communications in between Server A and Server B, Currently we don't have multicast,How to do this need your support.

many thanks,

[Vinit Jain]

Hello Mohammed

Could you please share the topology and the device details (what routers and switches you have)

Thanks

Vinit

[Peter Paluch]

Hi Mohammed,

This is a very extensive question that depends on where the servers are located, what is the network infrastructure that connects them together, and what kind of multicasting you would like to use.

In general, if these two servers are in the same IP network (that is, in the same LAN or VLAN) then the multicast should in fact work out of the box, without any specific configuration required on the switches. In some cases, the IGMP Snooping feature needs to be disabled on switches that connect these two servers together.

If the servers are located in different IP networks then the routers between these two networks need to be configured with IP Multicast routing support, and the PIM (Protocol Independent Multicast) needs to be started on these routers on all interfaces that will carry the multicast stream. PIM itself operates in several modes - Dense Mode, Sparse Mode, BiDir Mode. If your multicast deployment is very simple then PIM Dense Mode can be used. For more complex environments, PIM Sparse Mode is more effective but is slightly more involved to set up properly.

In any case, IP Multicast is a topic that, while it can be configured using no more than five basic commands, requires good knowledge of the underlying principles and mechanisms in order to be properly deployed, maintained, and troubleshot. Therefore, I do not recommend just starting the multicast and hoping for the best - ideally, I honestly suggest first doing a study on how the multicast works and what are the different modes of operation, and only then letting it run in your network.

Best regards,
Peter

[Jon Marshall]

Mohammed

I rarely post unless I have something to add but in this case I have to say I agree completely with Peter's comments.

Multicast is a large topic and it can be confusing if you have never used it before (it still confuses me now !).  It can also have an adverse effect on your network if you do not know what you are doing.

We could give you a basic set of commands based on your topology (if you provided it) but you really should understand at least the basics of how it works before you try and implement it.

Jon

[sherryvar]

Hello Mohammed,

I assume that this is an existing network and not one that is being newly deployed.

As our friends have pointed out, multicast is not a "plug and play" feature and is typically designed based on the need.

An prior assessment of the network has to be done before enabling multicast too[ as in, are u having the correct software versions, is it bug free for the service , should the network architecture be changed etc].

I would suggest to initially assess the need of enabling multicast on an existing infrastructure between 2 servers vs if the inter server communication could be achieved by other means [direct fiber, separate nic cards etc].

Hope this helps.