Expressway-E and H.323

[DemPackets]

I have a monthly conference that occurs with a parent organization. They basically use a tin can and a string and somehow initiate a conference call to our Expressway-E server using H.323 which I then have configured to forward to an sx10. This is an audio and video call. The problem is that for some unknown reason, the conference call terminates every 30 minutes. I was looking at the Expressway-E logging properties and I am trying to figure out what I need to configure from the webpage to capture the termination and see which side (my side or their side) is terminating the conference call.

Can anyone recommend some configuration settings to capture the termination on the Expressway-E?

[dpetrovi]

Hi,

Let me move this post to Telepresence community. This community is for Cisco WebEx Meetings Server and Cisco Unified MeetingPlace products and is not observed by TP/Expressway experts. 

I hope this will get you the answers you need faster.

Kind regards,

-Dejan

[DemPackets]

I appreciate it and I apologize for placing this in the wrong forum. My mistake. 

[Anthony Thomson · Accepted solution]

As far as I know, the Expressway-E will not be able to tell you which device is causing the termination.

You could have a device configured with a maximum call duration--the other endpoint, since SX10 does not support this call feature as far as I know--or, you have a device like a firewall that needs to be configured for longer timeouts.

See this thread: https://supportforums.cisco.com/discussion/12601586/h323-inbound-call-drops-after-5-mins-every-time

[Randy Valverde Rojas]

Hello,

You will need to read some logs but if you are familiar with sip/h323 it should be rather simple.

Firstly set the VCS on debug mode, depending on the version this might vary but for the latest just go to Maintenance >> Diagnostic >> Advanced >> Network.

Look for network and network.interworking and set them to debug.

Then go to Maintenance >> Diagnostics >> Diagnostic logging

Click on start logging (since the call is going for more than 10 minutes, I would recommend to uncheck the TCPDUMP while logging option since this could crash the VCS). Keep in mind all of the above needs to be done before the call starts.

Let the call follow its normal course and once it disconnects, click on stop logging and then download the log file.

Then it would just be normal log analyzing, if you have not done this before, I would suggest to open a TAC request but if you have then you might find it easy to go through the logs and find the root cause of why the call is terminating.

From previous experiences, calls dropping at specific minute marks (10, 15, 30 or 60 minutes) are firewall problems so you might run into that.

[DemPackets]

Thanks for the great write up. I don't think the problem lies with our equipment but I believe it's our partner's equipment. To test our H.323 connection system with the Expressway-E I installed the Polycom RealPresence App on an Android phone. I then used it to dial our global IP address and I believe that connection is an H.323 connection. 

We were able to successfully stay on the call for about 2 hours without a drop. I just need to prove beyond a reasonable doubt that it's not our system. 

[Randy Valverde Rojas]

Hi,

Understood, so yea if it works with other external equipment it will most likely be a problem on that specific site rather than your own. Still from the logs you can see what happens but I can almost bet that at the 30 minute mark you will see a round trip delay request that is not responded and causes the call to disconnect.

Hope I was helpful.

[DemPackets]

Would it be helpful to add network.h323 to the list of additional/upgraded logging?

[Randy Valverde Rojas]

You can but network and network.interworking already includes it so you should be fine.