Blocking SIP traffic inside an OpenVPN tunnel?

chedxb · Jan 3, 2018, 2:09 PM

I am running PfSense 2.4.2 and I have an Asterisk PBX behind the firewall. I also have an OpenVPN Server on pfSense for the SIP clients and an OpenVPN client on pfSense, connected to an OpenVPN Server on Azure.

LinPhone SIP client on an iPhone can connect to the OpenVPN Server on pfSense, then registers to Asterisk PBX and can call other extensions, as long as it is on the same LAN (over wifi) and entire traffic ends at the OpenVPN Server on Azure, as expected.

however, when I turn the wifi off on iPhone and test the same over 3G, I can connect to the OpenVPN Server on pfSense, can register to Asterisk PBX but cannot call other extensions. I get timeout error message on LinPhone. On the other hand, everything works fine and entire traffic ends at the OpenVPN Server on Azure, as expected.

I am not sure if my GSM operator is blocking my SIP traffic which is inside the OpenVPN tunnel (DPI?) or I did something wrong on pfSense and/or Asterisk settings.

Any assistance would be appreciated.

chedxb · Jan 4, 2018, 8:03 AM

tried with a different SIP soft-client (Zoiper) and it worked. It seems there is a bug in LinPhone.