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Multicasting b/w VLANs

Hi !

The scenerio is Like this :

I am on my laptop which is connected with the Access Switch 2950, The access switch is connected with the Distribution 3550 Switch and

3550 Distribution is connected with the Core Switch.

There are multiple VLANs and other locations are also connected in the same way with this Core swithc.I am trying for the multicasting audio /streaming.

CORE(config)#interface vlan 22 CORE(config-if)#ip pim version 2 CORE(config-if)#ip pim dense-mode CORE(config-if)#ip cgmp

CORE(config)#ip multicast-routing CORE(config)#interface vlan 99 CORE(config-if)#ip pim version 2 CORE(config-if)#ip pim dense-mode CORE(config-if)#ip cgmp

Access Switch is L2 switch and didnt use any command for multicasting.

I configured the following command on the Core Switch and installed a application for audio streaming LIVE CASTER. when i select the audio file and assign the IP address on the user of VLAN 22, the LIVE Caster starts the playing file but on the user of VLAN 22 there is no respone. I have debug ip cgmp , but didnt see any thing .

Where can be the problem? Where I need to make the changes ?

Reply to
Hemat Maheshwari
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the problem here is that you dont have enough info to understand where things are going wrong - so you need to do some testing to sort that out.

get it working locally within a single VLAN 1st. (if it doesnt the application / pc / server / IP stack is broken so no point going on).

then try it with the devices connected directly to a single layer 3 switch - use PIM v2 - i prefer sparse mode to make sure periodic flooding doesnt cause problems..

check that the layer 3 switch is getting the group registrations and that traffic is flowing in the hardware switching path - this is turned off by default on a Catalyst 6500 running in IOS mode

once it works on a single L3 switch you can add more switches and make sure the topology discovery and so on is working.

i would not use cgmp either (since it is cisco proprietary, and i havent seen a good enough description to let me hunt a problem with a sniffer) - if you must have layer 2 switches limiting where the streams go then maybe IGMP snooping is better.

Finlly if you campus has vlans that cross a lot of trunks, remember that you might get a copy of each stream in each vlan if there are recievers in each.

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Reply to
stephen

what value did you set the Time to Live (TTL) to ?

Reply to
Merv

Are you tried to stream the file to the IP address of the host on VLAN

22? That's not multicasting. The host on VLAN 22 should have a standard IP address, and you should configure the multicasting application to stream to a multicast address. You can safely use addresses in the 239.255.000.000-239.255.255.255 range.

Make sure that your receiving application is truly multicast compliant. The 3550 and 2970 will probably have IGMP snooping enabled by default. If the receiving application does not send out IGMP join requests, the distribution and access switches will not forward multicast traffic out the necessary ports.

Also check the TTL of the sending application.

Reply to
Mark Williams

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