TTAK/luksShrink

ubuntu LTS 18->20 luks volume shrik script

luksShrink

Ubuntu LTS 18 luks volume shrink script

Disclaimer, this script is not (yet) intended for production purpose. Do not use it on anything with important data and do a backup beforehand.

Version - Alpha 0.2 Work in progress

This script allow to shrink an LVM on LUKS Ubuntu Volume offline

Usage:

Usage: luksShrink -p <part> -s <size> [-g <volume group name>] [-h]
  -p <part> : Partition containing the LUKS volume to resize
  -s <size> : New desired size for the LUKS volume
  -g <volume group name> : Chose volume group instead of standard ubuntu-vg
  -h : Print this

For now, it should be only used it on a fresh luks full disk Ubuntu 18/20 install offline

It has been tested with Ubuntu 18 in EFI boot mode only but it should also work the same way on with the -g option to select the right Volume Group on Ubuntu 20

Usecases:

Create a working encrypted dualboot windows 10(Bitlocker) + Ubuntu 18/20(LUKS)

Ubuntu LTS 18/20 dualboot install :

1. Install Ubuntu on the whole disk with LVM+LUKS enable
2. Boot on it to check everything is working
3. Reboot on the live usb of ubuntu LTS 18/20
4. Execute this script to shrink the LVM on LUKS volume of ubuntu to get space for Windows 10
5. install Windows 10 on the free space
6. reboot on Windows and check everything is fine, DO NOT ENABLE BITLOCKER AT THIS POINT
7. reboot to modify back EFI boot in BIOS to ubuntu(Grub)
8. Boot on Ubuntu and do a >sudo update-grub
9. Reboot on windows using Grub and enable bitlocker.
10. You should now have a fully fonctionnal encrypted dualboot windows 10(Bitlocker) + Ubuntu 18/20(LUKS)

Examples :

luksShrink -p /dev/nvme0n1p3 -s 200G

is going to shrink /dev/nvme0n1p3 to 200G using ubuntu-vg as default volume group

luksShrink -p /dev/nvme0n1p3 -s 300G -g vgcustom

is going to shrink /dev/nvme0n1p3 to 300G using vgcustom as volume group