multicast routing problem

[songstadw]

I have inherited a school network with multicast speakers in 3 schools. It seems that the previous admin struggled with setting up multicast routing and it appears that he set up the network with a mixture of PIM-SM and DVMRP. We have abandoned DVMRP but there are a lot of fragments remaining. We have multicast streaming in one school, but we think it is switched layer 2 all the way from the school to the server network. We would like to set up the next school using multicast routing. I am struggling with the concept of which PIM interfaces must reside where. Here is my topology:

IP PIM sparse mode

School speakers all connected to AL 6450 switches on VLAN 92 at ALL schools.
School routers are AL 6900 using OSPF to route traffic to the core on VLAN 690. (there are lots of other Vlans also coming to the core from the schools, but we want to reduce that so the traffic is actually routed layer 3 and not just riding the vlans all the way)

The school that works has IP PIM interfaces for VLAN 92 and VLAN 690 on each router all the way to Multicast Source. It is also forwarding VLANs 92 and 690 to the core (which makes me believe that it is working using IPMS and not IPMR.
The school that doesn't work also has PIM interfaces for VLAN 92 and 690 on each router to the core but the site router is not forwarding VLAN 92.

Here is one of the many places it gets sticky: VLAN 92 at school 1 (the working one) has the routed interface 10.60.92.1/24. The core has the interface 10.60.92.10 on VLAN 92.
VLAN 92 at school 2 (the broken one) has the routed interface 10.50.92.1/24.

Since the core already has an interface for VLAN 92, I can't match the config for the working school, but I don't think I even want to because I suspect it is using IPMS instead of IPMR.

My question is What can I do to get IPMR working at the broken school? Shouldn't IPMR on the school router take the traffic from the IP PIM interface on VLAN 92 and route it onto the IP PIM interface on VLAN 690 and send it to the core? Clearly I am missing something about how Multicast routing actually routes. Can anyone help me?

Thanks Bill.

[tddupree]

Hi Bill,
In synching with a sales engineer here at ALE, he asked... does this has anything to do with the layer 2 (IPMS) vs. layer 3 (IPMR)? The OS6450 is only a layer 2 switch (w/no support for PIM or DVMRP, which are Layer 3 multicast protocols). Perhaps, the school that is working the multicast mac addresses were statically configured in the 6450 and they aren't configured in the school that not working. Those are my guesses by not having the exact traffic captures, or packet drop counters in the 6450.
In the meantime, maybe this will help:
Network configuration guide: https://www.al-enterprise.com/-/media/a ... 2-reva.pdf

He also suggested...I would repeat the same steps for the 6450; The network configuration guide would be sufficient and the user can perform global searches to find the multicast related syntax and configuration options: https://www.al-enterprise.com/-/media/a ... 5-reva.pdf

Hope it helps.
Cheers,
Tracy
ALE Curator of Customer Happiness

[songstadw]

Thanks for checking in Tracy. Though I wasn't able to answer all my questions about IPMS and IPMR, I was able to get multicast routing working at the non-working school. And at the same time add evidence to my theory about the already working school. The broken school was broken because OSPF wasn't configured correctly and multicast wasn't making it to the correct upstream router. I still have testing to do to remove the layer2 IPMS from end to end at the other school. But Multicast is now routing at the other school now that OSPF is working correctly.

[tddupree]

Good to hear!
Would you mind me asking what school district you're from? It will help me in the sorting of my role.
Thx!

[songstadw]

Sure, but it doesn't look like you have PM enabled Tracy.

[tddupree]

Hi Bill, I did receive the note above in my Unleashed inbox. I was tardy coming back to you here.
Thanks for the correspondence. Did I miss your reply on my Q "Would you mind me asking what school district you're from? It will help me in the sorting of my role."
Thanks,
Tracy