Some Outbound Calls will Randomly Not Work

[Huddles18]

Hey everyone,

CallManager newbie here. I am having an issue with CUCM 10.5. I have some users telling me that when they call an outside number, that their phones will drop the call. They do not receive a ring tone, or anything. Other times, dialing the same number will work. We are on PRI, and I confirmed that the connection is not getting overloaded (12 concurrent calls was the peak last week).

I'm not too sure where to go on this one. Does anyone have any suggestions on where I should be looking to gather more information, or fix this issue?

Thank you all for your help!

[Huddles18]

No love on this one?

[Adam Pawlowski]

You should be able to access /car/ and review the records for those calls to see what may be terminating them. 

It it could be some sort of media resource issue , like a lack of transcoder , or a channel issue with your PRI . Is it fractional? 

Most things are going to be all-or-nothing straight forward that aren’t capacity or round robining issues. Insufficient bandwidth or cal limits on the gateway will reject calls, though those should be a fast busy. Same with checking “run on all nodes” in the SIP trunk to the gateway and not having all nodes in the allow list or peer configurations. 

Once you you have a direction you can try and debug/log/test until you can reproduce and isolate the issue if it isn’t obvious sonewhere along the way.