How to create a bootable image of an encrypted TUXEDO OS installation as a backup? - TUXEDO Computers

TUXEDO regularly receives enquiries from customers about the recommended procedure for backing up an encrypted system completely and how to restore it if necessary. This article explains the recommended way to do this.

Several ways

As is usual with Linux, there are several ways to achieve this. You can make a bit-by-bit backup of the entire installation on the command line with dd or use a dedicated application such as Clonezilla or Rescuezilla for this purpose. Both applications also use dd in the background.

Rescuezilla is a GUI for Clonezilla, which itself can only be operated via a TUI (text-based user interface). Therefore, we recommend the easier-to-use Rescuezilla, which is 100% compatible with Clonezilla. Unless, of course, you know better. You can use Rescuezilla on Linux, macOS and Windows. The images of your chosen application must be placed on a USB stick and started as a live environment from there.

We have already described the general approach with Rescuezilla in another article for an unencrypted backup. This article follows on from that, but goes into the special features for encrypted systems.

Creating the backup image

To create a bootable image of your installation, first download the ISO image. You can find it on the Rescuezilla website. It is 1.1 GByte in size and therefore fits on a 2 GByte USB stick. After the download, use a tool of your choice to transfer the ISO to a USB stick. For example, if not installed already, you can install KDE ISO Image Writer from the TUXEDO repository in the Discover software shop as a Debian package or as a flatpak in TUXEDO OS.

Boot Rescuezilla with the attached USB stick created in this way. Depending on the model, you can access the boot options of your TUXEDO by pressing the keys F2, F7, F12 or ESC several times. There you select your USB stick as the medium to be booted from. After starting, first select the desired language and start Rescuezilla with the preselected top entry.

After clicking on Next you have a simple GUI in front of you, where you only need the two buttons Backup and Restore for the scope of this article.

After clicking on Backup, select the source drive in the next window. This is the drive on which your encrypted installation is located. It should have crypto_LUKS at the end of the line.

Clicking Next again lists the partitions found on the source drive you specified. These are partitions for EFI, boot and the actual installation of TUXEDO OS. By default, all three are marked with a blue box in front of the name. If this is not the case, make up for it before proceeding. Otherwise, a restored image will not be bootable.

The next step is to select the target drive. The first question is whether the desired drive is directly connected to the computer or connected via network. In addition to directly connected external drives, it is also possible to use an SMB/CIFS or NFS network drive. You can then recognize the desired drive by its size.

Almost there. The next three windows do not require any input. In the first window you can define a directory that will contain the image. In the second window, you can give the image to be created a name and add a short description. The third window allows settings for compression.

The default setting is gzip, alternatively you can select bzip or zstandard. If necessary, you can set the degree of compression using a slide switch. The more you move the switch to the right, the more compressed the image will be, but at the same time the time needed to create the image will increase. For a source drive with 500 GByte, this ranges from about one hour (factor 2 - 3) to 12 - 15 hours with high compression (factor 8 - 9). Clicking Next again will then show a summary of the settings made for review.

If you are satisfied with the settings and click Next again, Rescuezilla creates the image. In the middle of the window, a progress bar visually shows the current status. Below this, the estimated remaining time is displayed in numbers. Below this, while the image is already being created, you can select what action should happen when the process is successfully completed. By default, the computer stops when the success message is displayed. You can choose to restart the computer or to switch it off.

Restoring an installation

To restore a bootable installation, you again need a USB stick with Rescuezilla. Start the application in the same way as before, but this time use the button labelled Restore. It is important to note that the image cannot be restored to drives with a smaller capacity than the original source drive. The restore does not have to be done on the drive from which the backup was made. You can choose another drive on the same or another computer for this purpose.

The first step is to set the source drive. This is not asking for the original source, i.e. your installation, but the source disk lfor the restore!

After clicking on Next, select the backup to be restored. If you have more than one saved, by clicking on Browse you navigate to your backup copy and confirm with OK.

Your selection is then displayed in detail with size, date of creation and the partitions contained.

In the next step, select the target drive, i.e. the drive on which the backup is to be restored. It is the drive that is shown with the extension crypto.LUKS.

In the following step, you will see the selected target drive with the three partitions ticked. If one of the boxes is not highlighted in blue, tick it, otherwise accept the settings and click on Next.

Before restoring, Rescuezilla in a last step shows you, what will happen during the restore.

To start the restore, click Next one last time. Here you confirm again that you want to overwrite all data on the target partition and then see the progress bar already known from the backup. If you select Restart as the action to take after completion, you will land directly in your restored encrypted installation after the restore is done.

We found Rescuezilla to be very reliable as we tested it a couple of times during the writeup of this article. But it’s a known fact, that only a backup, that you have restored yourself for testing purposes makes sure, you have a valid backup.