Multicast problems

[E46Christian]

Hey all,

I'm having an issue with some multicast traffic being flooded to every port on the switch. We're using 2626's (H.08.92) and seeing 100% Tx utilization on ports where IPTV encoders are plugged in. The streams should be about 6Mbps and there's about 36 encoders - only 1 stream per encoder.

The multicast source switches are connected to 2 5304XL switches running PIM dense mode, with IGMP immediate-leave running on the edge switches.

The streams are being multicast on ip range 225.20.20.X. I'm not entirely sure if the 225 range will get flooded like the 224.x.x.x range
does.

Any help is greatly appreciated.

[Matt Hobbs · Accepted solution]

Hi,

I've gone through this one before...

The 2600's do not support data driven IGMP lke the 5300's do.

As such they support IGMP snooping which will flood any multicast groups that currently have no members on the same switch.

What I did to workaround this was to enable source port filters on the 2600's to only allow traffic between the encoder port and the uplink port.

If you have a network map that you can upload here, I should be able to go into more detail if you require it.

Most importantly though, I believe the issue you are seeing is because of the IGMP snooping support only on the 2600's. In my case source port filters was a suitable workaround.

Matt

[E46Christian]

Matt,

That did the trick.

Thanks a bunch for your help.

[Matt Hobbs]

No problem, you can also say thanks by assigning points to helpful posts.

How Do I Assign Points?
Only the question author can assign points to a given response. If you submit a question or new topic and another member replies to it, you will see a dropdown menu of points next to the reply (you must be logged in to see the menu). Select the point value and then click the "submit points" button.

[E46Christian]

Done!

Thanks again!