Ubuntu – Install Ubuntu 14.04 LTS with an already existing encrypted home


The issue is to upgrade a Ubuntu system mounted with an encrypted home (on a seperated partition) which then cannot be decrypted/mounted with the exact same passphrase on a new fresh installed Ubuntu. This question has already been answered but "solved" (?) in a "non-deterministic" way in 602360/345970. I cannot afford keeping reinstalling Ubuntu again and again…

I currently have a Ubuntu 12.04 that I cannot upgrade (via do-release-upgrade) due to package errors. Hence, I decided to make a fresh install of latest LTS Ubuntu 14.04. The system / directory (~50GB) is mounted on sda6 and yet the encrypted home /home is on sda7 (~145GB). I formatted and installed the new Ubuntu on sda6 and specified sda7 to be considered as a mount-point for /home.

After the install asked for a login/password (which I entered as the exact same as previous installs), I tried to log in. However, there appears that Ubuntu cannot decrypt/mount my data and shows the following

Signature not found in user keyring
Perhaps try the interactive 'ecryptfs-mount-private'

Morevoer, when I try ecryptfs-mount-private, it asks for the login passphrase which I correctly entered for a dozen times but an error appears claiming that the password is incorrect. I rolled back to Ubuntu 12.04 with a partition backup and checked again that the password was indeed correct.

Hereafter, I discuss related issues that are not relevant to this one or left unanswered:

  • 115497/345970: ecryptfs-mount-private is not an appropriate solution. Even if, my data is correctly decrypted, it requires me to allocate twice + 3/5 of the current home directory space disk to first decrypt and copy and then re-encrypt.
  • 129906/345970: Issue not answered but possibly the same (up to operating system version)
  • 182078/345970: Not related to the question of re-installing an operating system.
  • 286828/345970: Same issue but remained unaswered.
  • 341302/345970: My login passphrase is the same as the UNIX user password. Different issue.
  • 476037/345970: I'm not using LVM. In any case, that question was left unanswered.
  • 485625/345970: I'm not using different user login names.
  • 584656/345970: Same issue. No appropriate answer.
  • 602360/345970: As said earlier, "solved" in a random/non-deterministic way, by re-installing again and again Ubuntu until reaching a match.

Best Answer

  • It is really simpler than you think. All you have to do is that when installing the Ubuntu, you will see a page in the installation wizard called user settings. There you will fill up your system password and usernames. So down there you can see a check box says Encrypt my Home folder also All you have to do is that to check mark it and proceed as usual. It is easy to do.