How to shrink and clone a disk using Clonezilla

Here is a brief how to clone disks.

The practical example we use in this article is:

  • Windows Server
  • Magnetic hard drive media
  • 1 TB total disk space
  • 400 GB in use

Our objective is to have:

  • A perfect bootable replica of the Windows Server, it’s data and applications
  • SSD hard drive (for performance – in our example we used Western Digital Blue 500)
  • 500 GB total disk space
  • 400 GB in use (as it’s a replica)

In plain English we want to mirror backup our Windows from a magnetic hard drive to SSD. The destination disk is smaller than the source disk, but we have free space.

Procedure Outline

  • Shrink Windows Disk
  • Create bootable Clonezilla with Unetbootin
  • Specifiy icds and resize partition table proportionally


Clonezilla is amazing software that allows this operation. The idea is to create a Clonezilla bootable USB drive, plug it into the Windows Server’s hardware, and commence the operation.

The first gotcha is you have a bigger disk, although you don’t use all the space. Clonezilla won’t be able to fix this, you have to use Windows Disk Manager to shrink the disk.

The other gotcha is when you create the Clonezilla bootable USB, you need another tool, namely Unetbootin. The catch with using Unetbootin is that the default Clonezilla image is outdated – make sure you rather download the latest ISO when selecting an image. See references for links.

Once you have booted the Clonezilla (e.g. on a Dell press F12), then use expert mode. In the long list of Expert modes options, select this:

-icds option - Skip checking destination disk size before creating partition table

Then two screens later, be sure to check this as well:

Resize partition table proportionally

Be sure careful when choosing source and destination disks because you can make a big mess if you change them around by accident. Your data will be gone forever.

That’s it! In theory is should work, but please leave us a comment if you have any other tips or suggestions.


–Rescue option

If you have a bad disk, Clonezilla won’t complete it’s operation. However, there is a –rescue option, but be sure to download the latest version of Clonezilla because a force flag was only added on version 2.7.3-3. See here for the change log.

When downloading the latest Clonezilla, choose the Sourceforge repo.


Share this article

Leave a Reply

Your email address will not be published. Required fields are marked *

Scroll to Top