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Course Content - Intermediate

Backup and Restore


Welcome to the online training series from 3CX. This Module will take you through the procedure to backup and restore your 3CX PBX configuration.


By the end of this module, we will have covered all aspects of backing up 3CX. We will see the various options available within the backups, as well as the scheduling options.

We will cover the differences between Host and User data, explaining what these two types of data are, and what is considered as host and user data.

I will also share with you some neat tips which will make your job administering 3CX a breeze.


Let's start with the backup file. The backup utility of 3CX will store all the necessary information of the PBX into a single ZIP file, making it very easy to use.

The backup file can be used in a variety of scenarios:

For instance, if you need to change the hardware of the server, you can take a backup of the PBX, and install the PBX on a new host machine, restoring the backup during the installation process. This will restore all your settings to the new machine, without any cumbersome reconfiguring of the PBX from scratch.

If you want to migrate from a Windows based 3CX to the new Linux based 3CX or vice versa, you can do so by taking a backup and restoring your configuration to the other Operating System.

Currently, we are on Version 15.5 of 3CX. To upgrade from an older version, you are required to take a backup and uninstall the existing version of the PBX. Then, you will need to download and install the new version of 3CX. Please remember to download your backup file to a safe location on the server, away from the default folder of 3CX, as this will be deleted in versions older than Version 15.5 Service Pack 2, when you uninstall the PBX. I would also recommend performing all Windows Updates on the machine, if you are using Windows as your Operating System, and reboot the server before installing the new version.

They say, prevention is better than cure, and this is especially true when it comes to the administration of any mission critical machine, especially a PBX. It is recommended to take a backup of your 3CX configuration before you perform any administration tasks on the PBX. It only takes from a few seconds, to a few minutes, depending on what you are backing up. This way, if anything goes wrong along the way, you can very easily recover without any hassle.

If you are implementing a Version 15.5 failover scenario, with a standby Version 15.5 server, the information is transferred from one PBX to another via the backup file. There is no active information transfer on the fly and the backup file will be used in this case to transfer the information from one PBX to the other, on a schedule.


The Backup and Restore functionality can be found within the 3CX Management Console, in the “Backup and Restore” page, on the left hand side menu.

A backup can be created at any time, on demand. You can create as many backups as you require, in order to assist with restoring a PBX back to its previous state, before a reconfiguration is made.

A backup can also be scheduled nightly to provide you with a recent backup on a regular basis. This way if anything ever happens to your PBX, you will be able to have a recent backup to recover from. It is always a good idea to enable this, just to be on the safe side.

To enhance the security of the backup file, password protection is available, which encrypts the contents of the file, preventing any prying eyes from snooping the files within the ZIP file. As always, when dealing with passwords, please keep them safe, as losing this will render your backup useless.


Not all the data, however, is backed up by 3CX. There is some data, the “Host Data” which will always be configured on the host and will not be restored from a backup.

The SIP and Tunnel ports are examples of such data and will never be carried over from one 3CX to another. This is to allow the transition from either a multi instance, or Virtual PBX as it was previously called, or from another 3CX which may be using different SIP and Tunnel ports.

As already mentioned, the following backed up information will be restored. This is called user data.

Extensions and System Extensions.
VoIP Provider and Gateways.
Audio prompts and files.
The License key, FQDN and SSL certificate.


The backup file will always contain the main configuration of the PBX. Therefore whatever happens, you will at least have the configuration of the PBX. This includes the extension and extension group settings.
The SIP Trunk settings, as well as the respective inbound and outbound rules will also be included.

Any configuration of system extensions, for example, queues, ring groups and digital receptionists will also be backed up.

The PBX also provides you with some optional components which can be included in your backup.

For example, the License key information, FQDN and networking information can also be backed up or not.

The Call logs, chats and conferencing data will also be backed up if the relevant option is chosen. A large amount of Call history data, will cause the backup and restore procedure to slow down significantly.

Any system prompts, including custom system prompts as well as custom music on hold audio files will also be backed up.

Custom templates as well as IP Phone firmware files, can also be backed up. Have in mind that the firmware files can increase the size of the backup file drastically, as some of these are quite large files.

Another option which will affect the size of the backup is the Voicemails option. This will backup all the voicemail files in the system, and as these are audio files, depending on the size of the PBX, will increase the backup size substantially.

Call recordings will also increase the size of the backup file of the PBX.

This is where you will be able to create a password for the backup encryption, as well.


When you backup the PBX, the file will be saved, by default, in the 3CX Program Data folder. This location can be changed to another folder, for example the documents folder of the server.

You can also download the backup file to a safe location off the server, like an FTP driver or Google Drive, to avoid losing your information if your server hardware crashes, or is rendered unusable for any reason.


The recordings can also be placed onto a different path, for example a different hard drive on the server. Please note that only local disks are supported, as well as iSCSI and SAN drives. This is due to the recording location being required to always be available to the PBX. Network drives are not supported.

Compression is available to save on precious disk space, by allowing the admin to choose to save the recordings in ADPCM, or Adaptive PCM format. This realises a disk space saving of up to 75% over the normal PCM format.

So, every minute of recordings will take up to 256 kilobytes of disk space, rather than 1 megabyte with PCM. However, you will not be able to play the adaptive PCM format recordings in all media players, especially on mobile devices and browsers. You will need to have either a Media Player, like Windows Media Player of VLC.


To enable backup scheduling, click the “Backup Schedule” button while in the “Backup and Restore” section. Then, enable the scheduled backup.

Choose your backup options, just like you would for an on demand backup. They are identical.

Set the occurrence timer. Choose whether to perform a scheduled backup daily, or weekly and choose the desired time to perform the backup. It is best to choose a time when the PBX is not being in use. If the PBX is a busy PBX, choose a time when the PBX is not too busy.

Configure a retention policy, or as it is called in the management console, the backup rotation. This will allow you to keep a certain amount of previous backup files. If for example you choose daily and a backup retention of 25, you will have the backups from the last 25 days available in your list of backups.

[SLIDE 10]

Backing up via command line is also possible, making it easy to control your backups via scheduled tasks for example.

When using the command line functionality, all the backup options are available for selection, and you can even set a different local path for the backup you are configuring.

Please note that only local paths are supported in this case. The FTP and Google Drive options are not available in this case.

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Thank you, and goodbye!

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