How to Unlock Multiple LUKS Devices Using Dropbear-initramfs

Your problem is caused by booting with one virtual disk cloned from two physical disks. After manually booting, you could try this if you have md0 uncrypted and md1 crypted :

vi /etc/initramfs-tools/scripts/local-top/workaround_mdadm : #!/bin/sh sleep 5 mdadm --stop /dev/md1 mdadm --stop /dev/md0 sleep 5 mdadm --assemble --scan Note : Feel free to change the sleep values as well.

Make the file executable : chmod 755 /etc/initramfs-tools/scripts/local-top/workaround_mdadm

Create new initrd files in /boot : update-initramfs -k all -c

Reboot with your virtual disk and check if you are prompted for a passphrase.

I was able to fix the problem myself, but maybe someone else runs into the same problem, so I'll post the solution here:

As it turns out, my /etc/crypttab had syntax errors, which led to askpass(amongst others) not being included in the initramfs when running update-initramfs -u.

For me, it was enough to add each separate logical volume into /etc/crypttab instead of the volume group as a whole. Here's an example:

#name       underlying device       passphrase  cryptsetup options
vg-root     /dev/mapper/vg-root     none        luks,retry=1
vg-swap     /dev/mapper/vg-swap     none        luks,retry=1

After updating your initramfs once again your system should ask for the logical volume passphrases on startup and then resume booting normally.