How to check whether the downloaded Ubuntu 13.10 ISO image is corrupted or not in Ubuntu?

Towards the release of a major Ubuntu version, a lot of people writes to us seeking help regarding corrupted ISO image file problem. This can be because of so many reasons. At one point, the default Startup Disk Creator failed every time and I had to rely entirely on UNetBootin for creating Ubuntu based bootable USB drive. There can be other reasons too, prominent one being the .iso file corruption. Let's find out how to check the authenticity of an ISO image file (it can be Ubuntu or any other distro) that you downloaded for creating a bootable live USB.

ubuntu iso image authentication

How to check for authenticity of an ISO image before creating bootable live USB?
  • Actually, it is quite simple. There is CLI tool called 'md5sum' which comes pre-installed with most Linux distros and almost all Ubuntu variations.
  • Do the following in Terminal (provided that the ISO file is located in the ~/Downloads directory, which is case for all downloaded files by default in Ubuntu).
cd Downloads
  • Make sure that it's 'Downloads' and not 'downloads'.
md5sum ubuntu-13.10-beta2-desktop-amd64.iso
  • Please note that the file name (the one starts with 'ubuntu-' in the above command) will change depending upon the version and kind of Ubuntu ISO you downloaded. Now, the result will be something like the following:
ef56241339ab7421d883875c694f6995  ubuntu-13.10-beta2-desktop-amd64.iso
  • Copy the highlighted alphanumeric part from the Terminal (keyboard shortcut: SHIFT + CTRL + C) and goto Ubuntu Hashes page.
  • Type CTRL + F to bring up the find box in your browser (Firefox or Chrome). Search for the hash as calculated by the md5sum tool. If it is there, you're good to go.
  • Done. Have any doubts? Let us know.