How to raise PBX Huawei eSpace 1960?

Question

Computer networks

Essence of the question. In stock Automatic telephone exchange (the unified gateway everywhere according to the documentation) eSpace U1960, the local telephony is configured. A week ago, the provider submitted an E1 stream, they more or less figured out the incoming calls, but it was very difficult with outgoing calls. From the Chinese documentation, the brain is already exploding, we did everything in stages, we follow strict instructions. All that we have achieved is a response from the city PBX "the number is dialed incorrectly" with any setting of any prefixes. Complete misunderstanding of the logic of this miracle of Chinese engineering. If Huawei switches were somehow given in the study, then I got into a complete hopeless dead end. If someone has come across it before or in general with Huawei PBX, please respond)

Answer 1

Ask the provider what really comes from your PBX downstream.
There you will see what and where is cut or added.
SIP trunk will not be easier?