Unity Ring No Answer during Exchange Failure

[Vance Krier]

Howdy Unity experts,

I have a customer that is experiencing a really odd problem. On a number of occasions, they have experienced an Exchange failure of some kind. They're not exactly sure what is happening, but it appears the MTA and/or SMTP services are locking up and becoming non-responsive.

In any event, all inbound calls to Unity just ring no answer. I opened a TAC case, but neither they nor myself can find anything in the logs. The customer called me the last time it happened and I saw it for myself. As far as I can tell, Unity never sees the calls. Neither call viewer nor port status monitor show any activity. Callmanager sees the ports as online. Bouncing UMR made no difference. Bouncing Unity services brings it back online. Once Unity fails like this, it will not come back automatically even once Exchange service is fully restored.

We spent a couple hours the other night and could not reproduce the failure. We tried everything we could to Exchange and could not get Unity to fail. UMR kicked in and out of failsafe mode correctly in every instance.

Any ideas what we can do the next time this occurs to zero in on why Unity is failing in this manor?

Thanks,

Vance

[Erick Bergquist]

I have also seen this on some customers now and then. No good answers to why it happened. Unity not answering or not seeing calls indicates a possible TSP issue of some sort. I had one client have this problem more then others and upgrading them to a newer TSP version seemed to fix it as I haven't seen this issue with them in awhile.

[Vance Krier]

Thanks for the input. Any idea what version of TSP you were running before and after the problem?

Thanks,

Vance

[Erick Bergquist]

I believe it was a early 7.0(4) TSP and at time we updated to one of the earlier 8.0(x) versions. A lot of new TSP versions lately.