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I have recently installed ubuntu 12.04 LTS i686.I want upgrade it to 64 bit.How can I do it via terminal?

marked as duplicate by Eric Carvalho, Avinash Raj, karel, psusi, Oli Jan 23 '14 at 14:46

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  • Although it might be possible, I recommend do a clean install. – OrangeTux Jan 23 '14 at 10:53

Let's solve the problem. :-)

Before doing anything check the system requirements for Ubuntu x64. You can't upgrade directly to 64 bit from 32.

The safest and cleanest procedure is to do a backup of your personal data and, after that, a new installation of Ubuntu over the existing one. It will not harm or wear out your computer but be aware that the 64 bit versions are in some cases less stable and have different packages and (obviously) different bugs.

If you want to run a server there is Ubuntu Server, which is done specifically for that.

Follow my instructions to install Ubuntu 64 bit without losing your current software configuration:

  1. In a terminal execute sudo dpkg --get-selections > ~/softwarelist.
  2. Install the x64 Ubuntu over the existing one. If asked to preserve Home, say yes.
  3. Execute sudo dpkg --set-selections < ~/softwarelist.
  4. Execute sudo apt-get -f install. You will have some errors, but all should be fine.
  5. Reboot.

This procedure is valid for the 12.04, it can change with older/newer versions.

Please, press the UP arrow if I'm usefull and mark as best answer if you solve. Have a nice experience and comment down here for any issue, you'll be helped if possible.

  • Found I needed to run sudo apt-get dselect-upgrade, as per the notes associated with --set-selections in the examples section of the dpkg manpage. – RobM Jul 16 '14 at 12:40
  • Thank you for your advice! :-) I suggest to read the man pages of dpkg because new/older versions of Ubuntu may require additional steps. – Lorenzo Ancora Jul 16 '14 at 13:24

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