We are in the phase of migrating from cisco CME to 3CX. For security reasons the 3CX PBX is in a DMZ network and connects to the current CME via generic SIP trunk. The phones are also on the local LAN and pass through the firewall to reach the 3CX PBX. We used this document for ports opening but things didn't turn up right (https://www.3cx.com/docs/manual/firewall-router-configuration/)
- the SIP trunk between the 3CX PBX and CME was working unidirectional for calls signaling and there was no audio
- in general the system was not working well
- everything worked well when the firewall was removed
Questions :
- Are there other ports that should be opened to allow phones and CME from the internal network to work fine with the 3CX in the DMZ ?
- Is there a best practise design guide for the future when we'll have an external SIP trunk ? Where should one place the 3CX PBX ? DMZ or its advised to have it on the internal network together with the phones ?
- Is the port opening unidirectional or bidirectional ? According to the document , it seems to be unidirectional.
- Nat : Should we nat all traffic to the 3CX PBX ?
Thanks in advance
- the SIP trunk between the 3CX PBX and CME was working unidirectional for calls signaling and there was no audio
- in general the system was not working well
- everything worked well when the firewall was removed
Questions :
- Are there other ports that should be opened to allow phones and CME from the internal network to work fine with the 3CX in the DMZ ?
- Is there a best practise design guide for the future when we'll have an external SIP trunk ? Where should one place the 3CX PBX ? DMZ or its advised to have it on the internal network together with the phones ?
- Is the port opening unidirectional or bidirectional ? According to the document , it seems to be unidirectional.
- Nat : Should we nat all traffic to the 3CX PBX ?
Thanks in advance
