I have a problem with my CUCM solution. I have 2 CMs with version 18.104.22.16800-5 installed in differente sites. One CM is installed in the main office and the another one is installed in a remote site. There is a WAN connection between them. By the way, These CMs are not in cluster, they are independent. In the main office we have a gateway H.323 that has a E1 PRI line to PSTN. There is a conexion to the PSTN only from main office, we have no connection to the PSTN from the remote site.
The problem is the following: When an extension of main office receives a call from PSTN and someone wants to transfer the call to an extension of the remote site, the phone rings but when someone lifts the handset to answer, the call drops.
We have set up a intercluster trunk between the two CMs. Calls between IP Phones in different sites work well. The problem is when the caller is on PSTN and wants to communicate with an extension of remote sitte.