[min. installation] Cannot change Passphrase.

[Alexander Traud]

Since Ubuntu 18.04 LTS, a minimal installation is possible with the Ubuntu installer. If I go for that and choose to encrypt the disk, I cannot change the password via the utility gnome-disks graphically afterwards.

Steps to Reproduce
1. install Ubuntu 18.04 LTS (daily 20180420 and Beta 2 tested)
2. encrypt the disk, while going through the installer
3. after installation: Disks (3.28.1) » (highlight) Partition 3 with LUKS (open padlock icon) » (button with two cog-wheels) Options » Change Passphrase » …

Expected Results
The password should be changed. Or if a software package is missing for this, it should install that. At least, a note should appear how to install/add that package.

Actual Results
“Error changing passphrase on device /dev/sda3: The function 'bd_crypto_luks_change_key_blob' called, but not implemented! (udisks-error-quark, 0)”

Workaround
sudo apt install libblockdev-crypto2
After that, a log-off was not sufficient; instead I had to restart the computer. Before I found that, I was able to change the password non-graphically thanks to <https://superuser.com/a/431832>.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.