The reason why I do not think this is a duplicate is because I need to access data within a program called Wekan. I do not know how to extract that data from Wekan by mounting the ISO, which is why I am hoping to boot from the ISO.


I created a full backup of Ubuntu 16.04 using the command:

sudo dd if=/dev/sda of=/some_folder/backup.iso

So the backup includes the full drive, including all partitions etc.

I then installed Ubuntu 18.04 and realized I forgot to copy over something from Ubuntu 16.04.

Is it possible to boot into the 16.04 iso file and load the operating system using 18.04?

Also, the 16.04 drive is encryption and I do have the passphrase to access it.

  • Can you not open it with Archive Manager? It may give you option to extract, but I think you can just copy what you want.
    – oldfred
    Dec 15, 2018 at 21:30
  • @oldfred - On my old installation, I have Wekan installed with some tasks I needed to do. Not sure how to extract that data? Dec 15, 2018 at 21:54
  • 1
    You don't have an ISO image. You have a disk image. You can mount this following the instructions in the duplicate, and access it. No need to boot from the image - which would probably be a bit tricker.
    – vidarlo
    Dec 15, 2018 at 21:59
  • @vidarlo - I'm unsure how to extract data from Wekan once the disk image is mounted, which I why I was hoping to be able to boot from the image instead. Dec 15, 2018 at 22:27
  • 1
    To boot from it you have to write it back to disk, or convert to a virtual machine image. Once you mount it you an copy files as normal from it.
    – vidarlo
    Dec 15, 2018 at 23:07

1 Answer 1


If you would be able to identify the files, that you need,

  • You should be able to mount the partitions with file systems according to the following link, Mount dd image for my USB. kpartx is probably the best alternative.
  • When mounted, you can browse the file systems via the mountpoints and look for the files that you need.
  • The encryption is a complication, I have not tried to mount an image of an encrypted drive ...

If it is necessary to boot,

As suggested already in a comment, we don't think that you can boot from the image file. Instead

  • you can get a new drive, that is big enough,

  • and clone from the image file to the new drive.

  • If there is a GUID partition table, GPT, and the target drive size is different from the original one, the backup table at the end of the drive must be fixed with gdisk. This is done automatically by mkusb, so it is a good idea to clone with mkusb. Rename the image file to backup.img, to tell mkusb that it is an image file, not an iso file.

  • Replace the current drive with this new one and boot from it. Do not boot when both drives with installed systems are connected.

  • @unutbu, If the backup is a cloned image file created as shown in the question, it is complete with boot sector, partition table and file systems, including UUIDs that match the /etc/fstab and other things, that you have to consider, if you backup at the file level. But if the partition table is GPT, and the target drive is different from the original one, the backup table at the end of the drive must be fixed with gdisk (which is done automatically by mkusb).
    – sudodus
    Dec 16, 2018 at 2:30
  • My mistake. I had thought the UUIDs were hardware-dependent.
    – unutbu
    Dec 16, 2018 at 2:58
  • @unutbu, Thanks anyway for your comment. It reminded me of the GPT backup table :-)
    – sudodus
    Dec 16, 2018 at 3:08

Not the answer you're looking for? Browse other questions tagged .