Firewall & Router Configuration for 3CX - On-Premise Server

If you have 3CX installed on-premise you need to make changes to your firewall configuration to allow 3CX to communicate successfully with your SIP trunks and apps. This guide gives you a general overview of the ports that need to be opened/statically forwarded on your firewall. 

If you have remote IP phones, you need to put an SBC or router phone in front of them. Alternatively we recommend the use of our apps which have an inbuilt tunnel. More information on SBC can be found here.

Ports required for your SIP Trunk / VoIP Provider

Open these ports to allow 3CX to communicate with the VoIP Provider/SIP Trunk and WebRTC:

Ports required for remote 3CX Apps & SBC

To allow users to use their 3CX apps remotely, on Android, iOS or Windows, you need to ensure that these ports are open:

Configure the ports for remote 3CX clients

PUSH messages are sent by the 3CX System to Extensions using smartphones to wake up the devices for calls. This greatly enhances the usability of the smartphone apps. 

Ports required for 3CX Video Conference

To create and participate in web-based meetings, the 3CX-hosted cloud service must be able to communicate with the 3CX PBX and vice versa. To do so, these ports need to be configured:

Ports required for Other Services (SMTP & Activation)

A 3CX System connects to various services provided by 3CX in the cloud.

Other configuration


Revision #3
Created 11 December 2023 22:05:57 by Vox Tandem Admin
Updated 22 May 2024 19:19:05 by Vox Tandem Admin