[Serusers] Need help for Installing SER as Proxy

[Kai Dietrich]

Maybe I am stupid, but since two weeks I will install SER with RTP Proxy 
as Proxy in our Network.

The Situation. We have an new PBX System, with has direct SIP support. 
In the local network all works fine. But we want to add external Clients 
without VPN.
For this reason I have installed a new server with two network Devices. 
One Device has an Public IP from the Internet, the other one a local IP.

On the VoIP Device, wich I want to connect to our PBX via Internet I 
have adminstrate the internal PBX IP as Registra/Proxy und the Public IP 
as Ourgoing Proxy.
With the constellation and many configurations I have found in the 
Internet the Register works and I can call an Internal telephone. But 
from the same telephone I can't call the VoIP device. And also it looks 
so, that the RTP Proxy dosnet work.
The third problem is, that the PBX will send the UDP Packets direct to 
the Internet and not to the Proxy.

I have also tested siproxd. With this programm I have an working 
constallation. The Problem is, that only one Client can be register. But 
I want much more.

Can you help me, what I must configure that it works?

Kind regards,
Kai Dietrich