How to Use Clonezilla for Creating System Images on Debian 12 "Bookworm"

Creating a system image is a vital task for anyone who wants to back up their operating system, data, and software configurations. Whether you’re a system administrator, a home user, or an IT professional, having a reliable disk imaging solution can save you from the nightmares of data loss or system failure. One of the most powerful and open-source tools available for this purpose is Clonezilla. In this guide, we’ll walk you through the steps to use Clonezilla to create a system image on a Debian 12 “Bookworm” system.

🔍 What Is Clonezilla?

Clonezilla is a partition and disk imaging/cloning program similar to Norton Ghost and Acronis True Image. It helps you do system deployment, bare metal backup, and recovery. Clonezilla supports a wide range of file systems including ext2, ext3, ext4, reiserfs, xfs, jfs (Linux), FAT, NTFS (Windows), and HFS+ (Mac OS). It’s efficient and powerful, capable of saving and restoring only used blocks in the hard disk, increasing both speed and compression.

There are two main versions of Clonezilla:

• Clonezilla Live: Ideal for single machine backup and restore.
• Clonezilla SE (Server Edition): Designed for massive deployment across multiple systems over a network.

In this article, we focus on Clonezilla Live, and demonstrate how to use it on a Debian 12 “Bookworm” system.

🛠️ Prerequisites

Before you get started, make sure you have the following:

• A working Debian 12 “Bookworm” system.
• A USB drive (at least 1 GB) for the Clonezilla Live ISO.
• An external storage device or secondary drive with enough space to hold the system image.
• A backup of your important files (as a precaution).
• Basic understanding of Linux terminal commands and partitions.

🧰 Step 1: Download Clonezilla Live

Visit the official Clonezilla website and download the latest stable release of Clonezilla Live ISO.

URL: https://clonezilla.org/clonezilla-live.php

Choose the appropriate architecture for your system (most modern systems will use amd64). Download the ISO file.

💽 Step 2: Create a Bootable Clonezilla USB

To use Clonezilla Live, you need to create a bootable USB drive. You can use tools like balenaEtcher, Rufus (on Windows), or the dd command in Linux.

Using dd on Debian 12

1. Insert your USB drive and identify it using:

   lsblk
   

   Suppose your USB is /dev/sdb.

2. Run the following command:

   sudo dd if=clonezilla-live-*.iso of=/dev/sdb bs=4M status=progress && sync
   

   ⚠️ Be very careful with the device name /dev/sdb. Double-check to avoid wiping another drive.

3. Once done, safely eject the USB:

   sudo eject /dev/sdb
   

🔄 Step 3: Boot from the Clonezilla USB

1. Insert the Clonezilla USB into your Debian system.
2. Reboot the computer.
3. Enter the BIOS or UEFI menu (usually by pressing F2, F10, F12, or DEL during startup).
4. Select the USB drive as the boot device.

You should now see the Clonezilla boot menu. Choose:

Clonezilla live (Default settings, VGA 800x600)

Wait for the system to load.

📦 Step 4: Start the Clonezilla Wizard

Once Clonezilla Live boots up:

1. Choose language: Select English or your preferred language.
2. Keep the default keymap unless you need something specific.
3. Select “Start Clonezilla”.
4. Choose device-image mode to work with disk images (not disk-to-disk cloning).

You’ll be prompted to choose where the image will be saved.

💾 Step 5: Select Storage for the Image

Clonezilla needs a location to save the system image. You can use:

• A mounted local disk
• External USB drive
• NFS/Samba server
• SSH server

Example: Using a Mounted Local Disk

1. Choose local_dev to use local devices.
2. Connect your external USB drive if you haven’t already.
3. Wait a few seconds and press Enter.
4. Choose the external drive from the list.
5. Select the directory (or create a new one) to save the image files.
6. Press Done when ready.

📸 Step 6: Choose the Mode – Beginner or Expert

You can choose either:

• Beginner: Default recommended settings.
• Expert: Customize compression, file splitting, etc.

For most users, Beginner is sufficient.

Then, choose:

• savedisk to create an image of the entire disk.
• saveparts to image specific partitions only.

Let’s choose savedisk for full system backup.

You’ll be prompted to name the image directory, for example: debian12_backup_2025_04_06.

💿 Step 7: Select the Source Disk

Now, you’ll see a list of available disks. Choose the disk you want to image (typically /dev/sda if Debian is installed on that disk).

Confirm the selection when prompted.

⚙️ Step 8: Additional Settings and Confirmation

Clonezilla may ask if you want to check or repair the file system before imaging—select No unless you suspect issues.

You’ll also be asked whether to use compression. The default is gzip, which balances speed and compression size.

Other prompts may include:

• Splitting image files if they exceed a certain size (default is 2GB).
• Enabling encryption (optional).
• Confirming all selections before proceeding.

Finally, Clonezilla will show you a summary and ask for final confirmation.

Type y to continue.

⏳ Step 9: Wait for the Imaging Process to Complete

Clonezilla will begin creating the image of the selected disk and saving it to the destination folder on your external drive. This can take several minutes to hours depending on the size of your disk and USB speed.

You’ll see a progress bar along with messages showing read/write status and compression ratios.

Once it’s done, Clonezilla will prompt you for the next action:

• Reboot
• Poweroff
• Run more operations

Choose Reboot or Poweroff when you’re finished.

🔁 Step 10: Restoring the System Image (Optional)

If you ever need to restore your Debian 12 system:

1. Boot into Clonezilla Live again.
2. Choose device-image > local_dev.
3. Select the drive where the image is stored.
4. Choose the previously saved image directory.
5. Select restoredisk and then the target disk to overwrite.

Clonezilla will restore the image to your system exactly as it was when saved.

✅ Best Practices for Using Clonezilla

• Always test your backup: Consider restoring to a virtual machine or spare disk to ensure it works.
• Label your images clearly with date and system version.
• Keep multiple backups: Store one offsite or in the cloud.
• Update Clonezilla periodically to ensure compatibility with newer file systems and hardware.

🧠 Final Thoughts

Clonezilla is a robust and reliable disk imaging tool that works wonderfully with Debian 12 “Bookworm.” Whether you’re performing routine backups or preparing for a system upgrade, using Clonezilla can save you hours of reconfiguration and potential headaches. Though the interface is text-based, its powerful features and flexibility make it a favorite among Linux enthusiasts and sysadmins alike.

If you’re serious about system backup and disaster recovery, mastering Clonezilla is well worth your time. And now that you know how to create system images on Debian 12, you’re one step closer to having a bulletproof Linux setup.