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Installing 3CX on Debian Linux

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Step 1: Check System Requirements

Supported VM Platforms

Supported Mini PC’s

Network, Firewall & Other Requirements

Step 2: Install Debian for 3CX

Removing 3CX for Debian

See Also


3CX created a Debian Linux ISO (get ISO here) dedicated to 3CX to make installation faster and management easier. Most of the OS management can be done from within the 3CX Management Console.

We strongly recommend that you dedicate your Debian Linux instance to 3CX. Do not install other packages or change its configuration, as this prevents us from upgrading your operating system to a new version and providing support for your install.

Step 1: Check System Requirements

As a rule of thumb, your machine or VM needs at least one (1) CPU core and one (1) Gigabyte of RAM. Additional CPU time and RAM should be allocated based on:

  • Number of simultaneous calls the system handles.
  • Number of active users (100 users using the web client all day is very different from 100 IP Phones in hotel rooms making the occasional call).
  • Call recording use - places significant load on the system because of audio mixing and writing to storage.

Suggested hardware specifications for different usage scenarios can be found here.

Supported VM Platforms

The 3CX Phone System is well suited to be run as a Virtual Machine on tested and supported hypervisor platforms:

  • VMware ESX 5.X and above.
  • Microsoft HyperV 2008 R2 and above - see our Hyper-V Page for required settings.
  • KVM.
  • Citrix XenServer 7.0 and above.

Supported Mini PC’s

The 3CX Phone System has been tested on the following MiniPC models:

Network, Firewall & Other Requirements

  • If you are installing on LAN, your network must be properly configured using a RFC 1918 private network (e.g. IP / range).
  • If the machine you are installing 3CX on is behind a NAT device, its ports need to be forwarded. See the Firewall & Router Configuration Guide to learn how to do this.
  • Use the latest version of Firefox, Google Chrome or Edge to access the 3CX web interface.
  • The machine you are installing 3CX on needs a constant internet connection to
    on port 443.
  • The machine also needs on demand HTTPs connection to*
    for 3CX Management Console downloads and other info
  • To send emails via 3CX SMTP the machine needs to allow outbound TCP:2528.
  • See also Ports Used by 3CX Phone System for the list of required ports that need to always be available, i.e. not used by any other service.

Step 2: Install Debian for 3CX

To install Debian for 3CX:

  1. Download the Debian for 3CX ISO from here.
  2. If you are using a hypervisor/virtualized OS set the CD option to boot from the ISO and ensure the CD drive is set to connect on startup. If you are installing on a mini PC, then create a bootable image, plug it into one of the available Mini PC’s USB ports, set the BIOS to boot from the USB drive to start the installation.
  3. Boot your system with the downloaded 3CX ISO, select Install from the main boot screen and press the <Enter> key.

  1. Now enter a hostname for the computer so you can easily identify it on your network, using the characters 'a' to 'z', numbers '0' to '9' and the '-' character.

Important: If you need to configure a static IP address, press ESC when asked for the hostname to set the IP address of the system and then configure the hostname. If you don’t want to set a static IP address, enter a host name and select <Continue> to go to Step 6.

  1. Select “Configure Network Manually” and press the <Enter> key to set a static IP address. The installer will ask you to enter the system's static IP address and select <Continue>. Enter the network netmask and select <Continue>. Then, enter the network default gateway IP address and select “Continue”. Finally, enter the name server IP address and select <Continue>.

Note: The 3CX system’s IP address affects the running PBX services, connected clients and IP phones. To change the IP address on a running 3CX system, you need to reboot the machine and then re-provision the connected apps and IP phones.

  1. Enter a domain name - if this is a network, use the same domain you used on other computers in the network, for example
     After you enter the machine’s domain, select <Continue> to proceed.
  2. Select the language you wish to install as the default system language and press the <Enter> key.
  3. Select your geographical location from the location menu to update the system locale and press the <Enter> key to proceed.
  4. Specify the
    account password for the machine
     and select <Continue> to re-enter the password for verification purposes. Finally, select <Continue> to proceed.

Note: We recommend you set a strong password for the

user, as this account has no restrictions!

  1. Select your timezone to configure the system's clock and press the <Enter> key to proceed.
  2. Partition your disk, selecting “Guided - use entire disk”. Press the <Enter> key to proceed.
  3. Confirm your disk selection by pressing the <Enter> key.

Note: If you are installing on a bare metal machine, please remember that all the data on your disk will be erased!

  1. Select the “All files in one partition” partitioning scheme and press the <Enter> key to proceed.
  2. Select “Finish partitioning and write changes to disk and press the <Enter> key to proceed to the Debian for 3CX installation.
  3. Select Yes and press the <Enter> key to confirm writing the changes to the disk. The install process can take about 10-20 minutes, depending on your machine’s performance. When the Debian installer finishes, the machine is rebooted and the 3CX installation starts automatically.
  4. Choose the 3CX package to install on the “3CX Update Channel” screen:
  • 3CX Stable for the stable edition of the PBX and proceed to the next step.
  • 3CX Beta for the evaluation edition of the PBX and proceed to the next step.
  • 3CX SBC for the Session Border Controller edition of 3CX and follow this guide to configure the SBC.

  1. After the 3CX installation is complete, you need to run the configuration wizard. You can run this via a Web Browser or from the command line. Select option (1) to use a web browser on another machine, and point your browser to http://<ip of machine>:5015. Visit this guide for step by step instructions on running the first time configuration wizard.

Removing 3CX for Debian

In case you want to uninstall 3CX there are 2 options:

  1. Remove the 3CX installation, keeping all installation data (voice mails, database etc). To do this, run
    apt-get remove 3cxpbx 
  2. Remove 3CX including all installation data (voice mails, recording, database etc). To do this, run
    apt-get remove --purge 3cxpbx

See Also

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