0

I followed my own instructions here to shrink down a LUKS-encrypted Ubuntu 20.04 partition and its inner LVM volume so I could install Ubuntu 22.04 in a new LUKS-encrypted partition next to it, but after installing the LUKS-encrypted Ubuntu 22.04 OS, the LUKS-encrypted 20.04 installation (in a separate encrypted partition) is no longer in the Grub boot menu. Why? How do I get this dual boot to work properly? Should I have put both OS's in the same LUKS-encrypted partition, just in different LVM volumes within that partition?

Here's my disk, as shown in gparted while logged into the new Ubuntu 22.04 OS.

Description:

  1. /dev/nvme0n1p1 is the 512 MiB EFI partition
  2. /dev/nvme0n1p2 is the ext4 /boot non-encrypted partition for the old Ubuntu 20.04 OS
  3. /dev/nvme0n1p3 is the LUKS-encrypted partition containing a single LVM volume with Ubuntu 20.04 in it (no longer in the grub menu)
  4. /dev/nvme0n1p4 is the ext4 /boot non-encrypted partition for the new Ubuntu 22.04 OS
  5. /dev/nvme0n1p5 is the LUKS-encrypted partition containing a single LVM volume with Ubuntu 22.04 in it (is in the grub menu, and is the OS running right now)

enter image description here

These look potentially useful:

  1. Ask Ubuntu: How can I install Ubuntu encrypted with LUKS with dual-boot?
  2. Ask Ubuntu: how do I boot into a LUKS-encrypted environment? - helps me clearly see the definitions of LUKS-partition vs LVM vs logical volumes within it

1 Answer 1

0

I figured it out!

How to add other LUKS-encrypted Linux distributions back to your Grub bootloader startup menu: quick summary

# 1. Open your `/etc/default/grub` file.
sudo gedit /etc/default/grub
# Then manually add these lines to the bottom of that file:
# (required)
GRUB_DISABLE_OS_PROBER=false
# (optional)
GRUB_ENABLE_CRYPTODISK=y

# 2. Unlock your LUKS-encrypted partitions which contain other bootable
# operating systems. In my case:
sudo cryptsetup luksOpen /dev/nvme0n1p3 nvme0n1p3_crypt

# 3. Update your Grub bootloader in your `/boot` partition. 
sudo update-grub
# When I run `update-grub`, my output now includes this line:
#
#       Found Ubuntu 20.04.5 LTS (20.04) on /dev/mapper/system-root

# 4. Done. Reboot to see and use the new Grub entries!
reboot

For a ton more details and information, see my much longer answer here: Ask Ubuntu: How to get old LUKS-encrypted Ubuntu version back into Grub menu after installing new Ubuntu version in new LUKS partition

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .