I got a weired problem and I suspect it has to do with either openzap or libpri.
My setup is simple FS box, and a Sangoma E1 (A101) card.
Everything seems to be well configured and working. Yet, sometimes, when I call from the SIP the call failed, on the client I get "call ended" message.
On the server when looking at the log I see UNALLOCATED_NUMBER (line:274)
I can certainly tell that this number exists and alive and it is not a wrong number.
to make it even more complicated, calling that problematic number over and over, yields a statistics of working rate 5/1 that is every 5th or 4th call works
I placed here the logs of the working case and the not working case