High MTP Utilzation

[Sakitha Piyath Sudasinghe]

We have a Call center deployment consisting CUCM 9.1, UCCX 9.0. for PSTN calling we are using a Cisco gateway. Here we have one E1 and One SIP trunk. both the links are used as PSTN calling methods and fail over is configured using route lists. SIP trunk towards the GW from the CUCM is using MTP. Recently we got a customer complaints regarding internal/external call transferring getting a delay, incoming callers does not hear ringing tone. When we checked from RTMT all MTPs were utilized in both CUCM servers (no external MTPs are configured). However when checked from the from the CUBE there were only around 10 calls. MTP utilization is attached.

However after resetting the MTP servers the utilization comes back to normal and the issues gets fixed. How ever this happens regularly so we need to find the root cause. Can anyone have information on such an issue.

Thanks.

Regards. 

[Manish Gogna]

If the MTP utilization returns to normal after a restart then it is most likely a MTP leak issue where the MTP's that are allocated for a call are not being deallocated after the call is over. You should consider upgrading the cucm to the latest 9.1.2 version and upgrade the UCCX correspondingly by checking the compatibility matrix.

Manish