Multicast - PIM troubleshooting

[Sarah_Seidl]

Hello,
We have a location where our tech is reporting he cannot ghost image a computer lab (roughly 20 PCs). At that site we have a core of x670v-48x and x460-48p switches. Code is at 15.5.3.4 patch 1-5

We have pim setup in this fashion:

configure pim add vlan "IDF" sparse
configure pim add vlan "MDF" sparse
configure pim add vlan "JVloop" sparse
configure pim crp vlan "JVloop" "RP-list" 30
enable pim
configure pim cbsr vlan "JVloop"

When I issue the show pim command; I see the BSR elected and all the appropriate vlans rifms, with the JVloop rifmsc

Our RP-list.pol file is
entry rp-list { if match any{
}
then {
nlri 239.0.0.0/8;
nlri 224.0.0.0/8;
}
}

Igmp Snooping Flag : forward-all-routerIgmp Snooping Flood-list : none
Igmp Snooping Proxy : Enable
Igmp Snooping Filters : per-port

As a test, our tech plugged all the computers into a dumb switch and was able to mulitcast fine. He cannot multicast when he's connected to the extreme stack. When he is connected to the extreme stack, the clients are able to join the ghost server, but when he hits send to send them their images, it just spins then fails.

I've done the old stare and compare with other sites where I have been told multi-casting works fine, and I can't see a configuration difference.

I guess I'm looking for suggestions on what to try / tweak / look for?

Thank you

[davidj_cogliane]

I believe so. Here are links to packet captures from last week if you want to take a look.
https://www.dropbox.com/s/wocd9mjtd3zwjn3/AHD1P116.1.pc.png?dl=0
https://www.dropbox.com/s/8350ie9550fme5x/AHE-SRV_P23_Mirror_Filtered.pc.png?dl=0

Thanks,

[BrandonC]

Hmm, that does sound like a client issue with Ghost. I'm assuming you are mirroring the client port to take a capture? Do you see the stream making it all the way to the client when trying to use Ghost?

[davidj_cogliane]

Brandon,

That is the same tool we use, and in this case it works fine. It is just Ghost that fails, we have been trying to figure out if there differences between the the steams that could make one forward and the other not.

My latest WireShark captures seem to show everything working as expected but when I look at the logs on Ghost it is stuck in a re-transmit loop.

Thanks,

Ghost Log Level All 93736593 timed out after 1015 ticks

Wait(1000) timed out after 1016 ticks

93737609 Wait(1000) timed out after 1000 ticks

93738609 Wait(65) timed out after 78 ticks
93738687 Retransmit timeout

S: ACK TAK SEQ=4617902 ACK=347 WIN=57240 LEN=0 ADDR=10.10.5.108:7777
Slow start threshold 2862
Congestion window 2862

Wait(1000) returned (R) after 0 ticks

R: ACK TOK SEQ=347 ACK=4615040 WIN=57240 LEN=0 ADDR=10.10.5.108:7777
Recv would block

Wait(1000) timed out after 1016 ticks
93739703 Retransmit timeout
Slow start threshold 2862
Congestion window 2862

[BrandonC]

Hi David,

I generally use the UDP multicast test tool found at the following link if I'm testing in the lab.

http://members.home.nl/hbthouppermans/Skybuck/

You could use this in the network to see if you are able to get a stream routed from the server to client VLANs. If you are, then it looks like the network side is good and any issues may be client side.