3CX: Installing the PBX
Author: Kevin Fortune
Version: Applies to 3CX v18 / v20
Overview
This article outlines the installation process for the 3CX PBX on supported platforms. Follow the official 3CX guidance and ensure you meet all prerequisites before installing.
Supported Platforms
- Windows Server 2019 / 2022
- Debian 11 or 12 (recommended)
Prerequisites
- Minimum 4 GB RAM (8 GB recommended for 50+ users)
- At least 60 GB free disk space for recordings and logs
- Public DNS record pointing to the SBC or server
- Outbound & inbound required ports opened (SIP, RTP, WebRTC ports)
Installation Steps
Linux (Debian)
- Update the system:
sudo apt update && sudo apt upgrade -y
- Run the install script:
wget https://downloads.3cx.com/downloads/3cxpbx/install_3cxpbx.sh
sudo bash install_3cxpbx.sh
Windows Server
- Log on to the server as Administrator.
- Download the installer from 3CX Downloads.
- Run the installer, accept EULA, and follow prompts.
Post-Install Tasks
- Finish the Setup Wizard (enter license key, set admin credentials).
- Create recording directory if required.
- Open the 3CX Management Console and verify services are running.
Troubleshooting
- Installation fails on Debian 9: upgrade to Debian 11 because older Debian is not supported.
- Windows firewall blocking ports: enable PBX ports and allow ICS/UPNP if using NAT.
Need Assistance?
If you need help with your installation or migration, Deerfield’s 3CX-certified team is available for consulting support.
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