PIM Routing problem

[perpaal]

Hi I have set up PIM sparse mode between some sites. Site 1,2,3 and 4. On site 1 I get the multicast service from provider, and have set up an RP. Site 2 is behind site 1, and site 3 and 4 is behind site 2. First I set up separate VLANs with linknets from each site to RP. This works, but multicast traffic is tripled between site 1 and 2 (takes to much bandwidth). About 400Mbps to site 2, 100Mbps to site 3 and 4, that gave 600Mbps between site 1 and 2. Then I though I would set up just one VLAN, and have each site be a member of this, and set site 2 as DR (highest priority). Now multicast traffic between 1 and 2 is ok, around 400Mbps, but traffic to the smaller sites 3 and 4 grew a lot. It is almost like traffic is flooded to these sites also, even though there are few users there. Before doing this (when using separate VLANs) I had about 100Mbps multicast to these sites (3 and 4), now it is around 400Mbps (pretty much same as site 2). Problem is that I have limited capacity between the sites, and want to make most use of it. Any ideas what I have done wrong here?

[Jon Marshall]

Okay but you still don't have to use the same vlan ie. use a different vlan per site to site connection.

This vlan would be used purely for routing between sites including the multicast traffic and you could still have other vlans shared across all sites.

Jon

[perpaal]

Ok, and use router (L3 switch) in site 2, to route to the other two?
I can try that, sounds like a good idea :)

[Jon Marshall]

Yes, you simply need to make sure that each site uses a different vlan to communicate with the other sites for multicast traffic.

That way when site 2 receives multicast in vlan 200 it won't send it to sites 3 and 4 automatically.

What should happen is only the streams requested locally in each site are sent to that site.

No guarantees but I think it is worth a try.

Jon

[Peter Paluch]

Hi Jon,

Absolutely no objections to you joining the thread, quite the contrary. First, though, my sincere congratulations to your new platinum star! It is so awesome - and so much deserved, my friend!

I am increasingly getting a feeling that the network is more complex than just four switches with VLANs spanning all of them. Only now we're learning that there are VRFs involved. It is my belief that to be able to answer what is going on, we should really be seeing the exact physical and logical topology diagrams of perpaal's network. We definitely need to understand the scope of Layer2 broadcast domains (VLANs) and their boundaries including the routing points and routed interconnections, along with the placement of VRFs. Is it possible to provide a set of diagrams that would clear these details?

Best regards,
Peter

[Jon Marshall]

Hi Peter

Many thanks for the congratulations and please take my last post in the HSRP thread in the manner it was intended ie. continually trying to learn :-)

As you know I am of the strong belief my stars reflect my longevity on this forum as much any technical knowledge but I still very much appreciate the words.

Yes I think we need to understand the full topology together with the routing and PIM setup to get to the bottom of this.

Jon