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Clonezilla Save Disk Image Guide: Back Up a System Drive to Another Disk

Tue, 23 Jun 2026 15:55:19 +0800

Clonezilla Live can save an entire drive as an image directory, which can later be restored to a disk. The official example saves the first disk sda as an image and stores it on the sdb1 partition of the second disk.

Official document: https://clonezilla.org/fine-print-live-doc.php?path=clonezilla-live/doc/01_Save_disk_image

This is different from disk-to-disk cloning. Disk cloning writes the old disk directly to a new disk. Saving an image first packages the current disk as a backup and stores it on another disk, external drive, or network storage. When needed, you can later use restoredisk to write the image back to a target disk.

Do two things first

First, make sure the system you want to back up is fully shut down.

The official document specifically notes that the original system must not be in hibernation, Fast Startup, or a similar half-shutdown state. Windows users should pay special attention to Fast Startup. If the system is not fully shut down, the file system may not be clean, and the restored image may have problems.

Second, make sure the image storage location has enough space.

Clonezilla does not always save data equal to the raw size of the entire drive. It handles the image according to partitions, file systems, and actual data. Still, the storage disk needs enough free space. In the official example, sda is 20GB and the final image directory is about 1.3GB because the sample system contains little data. Do not use that as a general estimate.

Example scenario

The official example has two disks:

Device	Role
`sda`	Source drive to save as an image
`sdb1`	Target partition that stores the image

sda has Debian Bookworm installed and contains several partitions, such as sda1, sda2, sda3, and sda4. Clonezilla saves disk-level information, including boot information, partition table, partition data, and hardware/system records.

Do not judge by sda and sdb alone. Device order may change on different machines. Before selecting, check capacity, model, connection type, and partition information.

Boot Clonezilla Live

Boot the computer from a Clonezilla Live USB drive, CD, or other boot media.

If the machine does not boot from USB automatically, adjust the BIOS/UEFI boot order, or press the boot menu key during startup, such as Esc, F8, F9, or F12. The exact key depends on the machine.

In the Clonezilla Live boot menu, the default 800x600 mode is usually enough. The official document also describes several common choices:

Default mode: normal Clonezilla Live boot.
VGA 800x600 & To RAM: copy Clonezilla Live files into memory and run from there, allowing the boot media to be removed later.
VGA with large font & To RAM: useful for high-resolution displays or when larger text is needed.
Safe graphic settings: useful when framebuffer graphics cause problems.

Saving an image does not always require ToRAM, but if you want the boot media to be released later, or need to remove the USB drive, choose a mode with To RAM.

Enter device-image

After entering Clonezilla, choose:

Select language.
Select keyboard layout. The default is fine for a US keyboard.
Choose Start Clonezilla.
Choose device-image.

device-image means backup or restore through images. Saving and restoring disk images both use this entry point. Direct disk-to-disk cloning uses device-device.

Some Clonezilla menu items require the space key to select. The official hint says that when multiple choices are available, press Space; selected items show *.

Choose local_dev as the image repository

Next, tell Clonezilla where to store the image.

The official example chooses:

`1`	`local_dev`

local_dev is suitable when the image will be saved to a second local disk, external drive, or USB drive. After selecting it, Clonezilla scans local disks. If you use a USB drive or external drive as the image repository, insert it and wait a few seconds.

When the device appears in the scan results, press:

Ctrl-C

to exit the scan report and continue.

If you do not have a second local disk, you can choose sshfs, samba, nfs, WebDAV, S3, or OpenStack Swift depending on your environment. For a normal personal backup, local_dev is the simplest.

Mount the partition that stores the image

The official example chooses sdb1 as the image repository.

Linux device names roughly mean:

Name	Meaning
`sda`	First disk
`sda1`	First partition on the first disk
`sdb`	Second disk
`sdb1`	First partition on the second disk

If you save the image to an external drive, it may not be sdb1; it could be sdc1. Use capacity and device information to decide, and do not accidentally choose a partition on the source disk as the storage location.

Clonezilla asks whether to check the file system of the image repository partition. The official example skips it. If that disk was previously disconnected unexpectedly or you are unsure whether the file system is clean, checking first is safer.

Then select the directory where the image should be stored. The official example stores the image in the partition root /. Confirm the directory, use Tab to select Done, and press Enter.

Choose savedisk

After mounting the image repository, Clonezilla shows disk usage. Choose:

`1`	`Beginner`

Then choose:

`1`	`savedisk`

savedisk saves an entire drive image. It stores disk-level information and partition data, making it suitable for a full system disk backup.

If you only want to back up one partition, do not choose savedisk; choose the corresponding partition save mode instead.

Enter image name and select source disk

Clonezilla asks for an image name. It suggests a default name based on date and time, but you can rename it to something easier to recognize.

A useful name can include machine name, system, and date, for example:

`1`	`thinkpad-win11-2026-06-23-img`

Then select the source drive to save. In the official example:

sda

Be careful here. sda is the drive to read and save as an image, not the image storage disk. Check capacity, model, and partition count before continuing.

Compression, checking, and encryption

Clonezilla asks for a compression method. The official document mentions two common options:

-z1p

which uses parallel gzip.

-z9p

which uses parallel zstd and is usually faster, with a slightly smaller size than gzip.

Most users can choose the Clonezilla-recommended default. If speed matters more, consider zstd. If you prefer conservative compatibility, gzip is also fine.

Clonezilla then asks whether to check the source file system. The official example skips it, but it also notes that if you are not sure whether the source file system is clean, checking is recommended.

Next it asks whether to check the saved image. The default is to check, and the official document recommends doing so. This takes more time, but it can catch image corruption early, especially for important system disk backups.

Then it asks whether to encrypt the image. The default is no encryption. If you choose encryption, Clonezilla asks for a passphrase.

Be careful: you must remember the passphrase. The official document makes it clear that if you forget it, the image will not be usable later. There is no back door to decrypt it.

Start saving the image

After the options are confirmed, Clonezilla displays the actual command it will run. This command is useful for batch backups, custom Clonezilla Live media, or reproducible workflows.

Before starting, Clonezilla gives one more confirmation. After confirmation, it saves the source drive as an image. The official document says it usually saves:

MBR.
Partition table and disk CHS information.
Data on every partition or logical volume.

Different file systems are handled by different tools, such as partclone, ntfsclone, partimage, or dd. Ordinary users do not need to manage these manually. The important part is confirming the source disk and image storage location.

If you chose to check the saved image, Clonezilla automatically verifies it after creation.

What the image looks like

After completion, the image is not one large file. It is a directory. In the official example, the image directory is:

`1`	`bookworm-2023-10-15-03-img`

The directory contains many files, such as disk lists, partition tables, hardware information, file system images, and boot-related information. The official example includes files like:

blkdev.list
blkid.list
clonezilla-img
disk
efi-nvram.dat
Info-dmi.txt
Info-lshw.txt
sda1.vfat-ptcl-img.zst
sda2.ext4-ptcl-img.zst
sda-gpt-1st
sda-gpt-2nd
sda-mbr
sda-pt.sf

Do not copy only one compressed file. For future restore, keep the whole image directory.

What to do after completion

After saving the image, Clonezilla lets you choose:

Power off.
Reboot.
Enter command line.
Start over.

For a system disk backup, you can usually choose power off and safely remove the image disk.

It is also worth doing two more things:

Give the image directory a readable name, or record which machine, system, and date it belongs to.
Keep at least one extra copy. If the image exists only on one external disk and that disk fails, the backup is gone.

If the image is important, periodically use Clonezilla’s check function to verify that it is still readable.

Short advice

When saving a full disk image, remember this flow:

`1`	`device-image -> local_dev -> choose image repository -> Beginner -> savedisk -> enter image name -> choose source disk`

The points that deserve attention are:

Is the original system fully shut down?
Is the image repository partition correct?
Is the source drive correct?
Should the saved image be checked?
If encryption is enabled, is the passphrase stored safely?

Once these are clear, Clonezilla savedisk is a solid full-disk backup method.

Clonezilla Restore Disk Image Guide: Restore a Backup Image to a Target Drive

Tue, 23 Jun 2026 15:50:48 +0800

Clonezilla Live can restore a previously saved disk image to a drive. The official example restores the image bookworm-2023-10-15-03-img, stored on the second disk sdb, to the first disk sda.

Official document: https://clonezilla.org/fine-print-live-doc.php?path=clonezilla-live/doc/02_Restore_disk_image

This is useful for system recovery, batch deployment, lab rollback, or restoring a backup image to a new drive. Unlike copying files, restoredisk restores the full disk structure, including partition table, boot-related information, and partition data.

Confirm the risks first

Before restoring an image, confirm these points:

Data on the target disk will be overwritten.
The image files must be complete and readable.
The target disk should have enough capacity for the image.
The source image and target disk must not be confused.
For a system disk, BIOS/UEFI boot order may matter after restoration.

Clonezilla asks for confirmation twice before writing. Do not treat these confirmations as routine, especially when several disks or USB drives are connected.

Example scenario

The official example has two disks:

Device	Role
`sda`	Target disk, the first disk to be restored
`sdb`	Second disk that stores the Clonezilla image

The image directory is:

`1`	`bookworm-2023-10-15-03-img`

A Clonezilla image directory usually contains partition images, partition table data, disk information, hardware information, and metadata required for restore. The official example includes files such as sda-mbr, sda-gpt-1st, sda-gpt-2nd, sda1.vfat-ptcl-img.zst, and sda2.ext4-ptcl-img.zst.

Do not rename, move, or delete these files manually. When restoring, select the whole image directory, not a single compressed file.

Boot Clonezilla Live

Boot the machine with a Clonezilla Live USB drive, CD, or other boot media.

If needed, set USB or optical drive as the first boot device in BIOS/UEFI, or press the boot menu key during startup, such as Esc, F8, F9, or F12. The key varies by machine.

In the Clonezilla Live boot menu, the default 800x600 mode is usually enough. If display problems occur, try safe graphic settings. On a high-resolution display, the large-font mode may be easier to read.

Enter the restore flow

After booting, choose:

Select language.
Select keyboard layout. The default is fine for a US keyboard.
Choose Start Clonezilla.
Choose device-image.

device-image means backup or restore through image files, not direct disk-to-disk cloning. Disk-to-disk cloning uses device-device, so do not choose the wrong mode here.

Some Clonezilla menus require the space key for selection. The official document notes that when multiple choices are available, press Space; a selected item will show *.

Choose the image repository

Next, choose where the image is stored.

The official example chooses:

`1`	`local_dev`

local_dev is suitable when the image is on a second local disk, external drive, or USB drive. Clonezilla scans the local disks and partitions. If you have just inserted a USB drive or external disk, wait a few seconds for it to appear.

When the device appears in the scan list, press Ctrl-C to exit the scan report and continue.

If the image is not on a local device, you can choose other methods such as sshfs, samba, nfs, WebDAV, S3, or OpenStack Swift. For personal recovery work, local_dev is the most straightforward option.

Mount the partition that stores the image

The official example selects sdb1 as the image repository, meaning the first partition on the second disk.

Linux device names can be understood like this:

Name	Meaning
`sda`	First disk
`sda1`	First partition on the first disk
`sdb`	Second disk
`sdb1`	First partition on the second disk

If your image is on a USB drive or external disk, it may not be sdb1; it could be sdc1 or sdd1. Always judge by capacity, file system, and device model.

Clonezilla asks whether to check the file system before mounting the device. The official example skips it, but if you suspect the image disk has issues, checking first is safer.

Then choose the directory that contains the image. If the image is in the root of the partition, choose /, use Tab to select Done, and press Enter.

Choose restoredisk

After mounting the image repository, Clonezilla shows disk usage. Then choose:

`1`	`Beginner`

Then choose:

`1`	`restoredisk`

restoredisk restores a disk image to an entire drive. It is different from restoring a single partition and is suitable for full system disk recovery.

If you only want to restore one partition, do not choose restoredisk; choose the corresponding partition restore mode instead.

Select the image and target disk

First select the source image, such as:

`1`	`bookworm-2023-10-15-03-img`

Then select the target drive, such as:

sda

This is the most dangerous step. The source image is read. The target drive is overwritten.

Before confirming, check three times:

Is this the image you want to restore?
Is the target disk capacity and model correct?
Is there any unbacked-up data on the target disk?

Partition table and image integrity

Clonezilla asks how to create the partition table on the target disk.

The official document mentions two directions:

Use the partition table from the image.
Create the partition table proportionally on the target disk.

If the image was saved from a smaller disk and the target disk is larger, proportional creation may be convenient. But this affects the final partition layout, so do not change it casually if you are unsure.

Clonezilla also asks whether to check image integrity before restoring. The official document recommends checking the image because the directory existing does not prove that the image is intact.

If you are very sure the image is good, you can choose -scr to skip checking. For most recovery scenarios, checking first is better, especially when the image comes from an external drive, network storage, or old backup.

Start restoring

After confirming options, Clonezilla displays the restore command. This command is useful for custom Clonezilla Live media or repeatable deployment workflows.

If you chose to check the image, Clonezilla checks it first. After the check passes, it asks for confirmation twice before writing.

During restore, Clonezilla writes the image back to the target disk, usually including:

MBR and boot loader.
Partition table.
Data for each partition or logical volume.

Different file systems may be restored with different tools, such as partclone, ntfsclone, partimage, or dd. Ordinary users do not need to choose these manually; the important part is selecting the correct image and target disk.

What to do after completion

After restoration, Clonezilla lets you choose:

Power off.
Reboot.
Enter command line.
Start over.

If this is a system disk restore, it is usually safer to power off, remove the Clonezilla boot media and image disk, then boot from the target disk.

After booting, check:

Whether the system starts normally.
Whether partitions match expectations.
Whether important data exists.
Whether BIOS/UEFI boot entries point to the correct disk.

If the restored system does not boot, do not immediately redo everything. Check whether the boot mode is consistent, such as UEFI or Legacy BIOS, whether the target machine’s boot order is correct, and whether the ESP partition exists.

Short advice

When restoring a disk image with Clonezilla, remember this flow:

`1`	`device-image -> local_dev -> choose image repository -> Beginner -> restoredisk -> choose image -> choose target disk`

Spend your attention on:

Did you choose the correct image repository?
Did you choose the correct image directory?
Did you choose the correct target disk?
Should you check image integrity?
Has the target disk data been backed up?

Once these are confirmed, restoredisk becomes much safer.