Allowing Multicast to work between real servers behind the CSM??

[sgonsalv]

Hi,

Just want to know if it is possible to use IP Multicast between real servers on a server subnet that is configured on the CSM. If so how could this be setup?

I've attached a copy of the our CSM config. In particular, the server subnet in question is "vlan 386 server". The Real servers belong to "serverfarm FARM-VISTA-TEST".

I suspect that maybe an interface vlan 386 needs to be created on the router, with pim sparse-mode enabled?

Any ideas?

thanks

Sheldon

[Gilles Dufour]

the CSM does not know ip multicast, so your multicast needs to find another way to reach the servers.

You will also need a static route on the servers to point 224.x.x.x to the MSFC and keep the rest of the traffic going to the CSM.

Another solution is to use bridge mode.

Create a duplicate vlan 386 on the CSM and the MSFC.

ie:

MSFC---vlan387-----CSM-----Vlan386

On the CSM, you configure vlan387 with the same ip as vlan 386 - this will tell the CSM to bridge the 2 vlans.

Configure an ip from the same subnet on the msfc int vlan 387.

configure multicast on vlan 387.

The CSM should normally bridge all unknown traffic including multicast.

All you have to do on the servers is change the default gateway to be the MSFC instead of the CSM.

Gilles.

[sgonsalv]

Hi Giles,

After having done some testing, i've found that by just creating "interface vlan 386" on the MSFC, and enabling multicasting, multicasting on the real servers work, and also the balancing of traffic across these real servers. That is, i am still able to request pages while the multicasting is being performed. This also worked when testing in our lab. Didn't have to create a seperate interface on the CSM at all. Any thoughts?

thanks

Sheldon

[Gilles Dufour]

Sheldon,

as I said the goal is to have the multicast traffic bypass the CSM.

By configuring int vlan 386 on the MSFC, the multicast traffic can reach the host directly without going through the CSM.

If it does not have any impact on loadblanced traffic, than that is a great solution.

Gilles.

[cscales]

Did you assign an IP and have the servers route 224.x.x.x to the vlan386 ip?