Call disconnects while holding

[mesarasimth1]

Hi

We have Cisco Call Manager 10.5 and our clients use Cisco IP Communicator. We have a problem while holding a call, some times when a client holds a call for a minute, the resume button disappears and then the call disconnects ( I have attached the picture). There is no problem with holding internal calls and just external calls disconnect.

How can it happen?

[Mohammed Khan]

Have you tried upgrading CIPC to latest version. Is that compatible with UCM 10.5

[mesarasimth1]

Yes, there was no difference between the latest and previous version of CIPC.

[Mohammed Khan]

Worth checking CUCM Logs and CIPC PRT,

Let me know if you need any help collecting them.

[mesarasimth1]

I have tried using Syslog Viewer of RTMT and also the CIPC, but I couldn't find out anything useful. Is there any other way to achieve the logs?

[Mohammed Khan]

Refer below link to collect logs from CUCM

https://supportforums.cisco.com/document/126666/collecting-cucm-traces-cucm-862-tac-sr

[Ahmed Adeyemi]

Have you by any chance toggled with your MOH. I have someone experiencing the same issue that i will begin troubleshooting tomorrow as well. I will let you know what i find for this customer but i believe it may have to deal with MOH or resources.

[mesarasimth1]

Yes, we exactly guess that the root cause may be from MOH or resources.

I will appreciate if you could find any thing new and inform us.

Thank You

[Ahmed Adeyemi · Accepted solution]

Well, in my case, it turned out to be bigger than MOH. Although, once i check the MTP, the call begins to work and everything looks fine but this is not the ideal solution because now i am counting on every call going out that trunk to use the MTP resource. So i decided to dig deeper. 

My call is going from the SIP trunk to the CVP servers which at that point goes in to the UCCE cluster. From looking at the logs, the call seems to be waiting for some DTMF input which is not the anticipated design from the UCCE side and then i see the CUCM gets request to terminate the call. The CUCM gets the termination from CVP and CVP gets the termination request from the VXML gateway. The VXML gateway was requesting termination because during the hold period, it is somehow anticipating some DTMF which cause it to terminate due to no response.

For you, where i would start form would be to check the MTP and see if this works. Essentially, checking the MTP doesn't update the invite and just keeps the call as is from the setup. If this works, you can then uncheck it and place a call in the failing scenario. Once you place the call, pull the call manager log and check for the MOH resource being invoked and make sure its according to the expected codec you have in your environment. If the MOH resource is not being invoked properly, it would cause issues like this. If the MOH codec is coming in as something outside your setup, you may need to go into the service parameter and IP media streaming apps to ensure you select all 3 codec or the ones that applies to your setup vice leaving it as default g711u. Also keep in mind that once you make this change, you have to save it and restart the IP Media Streaming app service.

Also remember changes to your SIP trunk requires resetting the trunk so it will be best to do all these changes after-hours.

Please let me know what you find so i can assist you in resolving this.

also, sorry for the long notes. My head is going all over while thinking of what i was working on for one of my customers.

[mesarasimth1]

Thank You for your perfect guidance. I will check every thing that you mentioned and inform you.

[Robert Shaw]

Did something change recently when this started happening?  Also what sort of gateway do you have for external calls?  H.323 ISDN or SIP?  Do you have any fixed phones to test with?  We could do with identifying if it is a problem only with CIPC or if its all phones.