Resize a LUKS encrypted root partition

  1. Resizing the partition used by the encrypted volume
parted /dev/sda

(parted) print
[...]
Number  Start   End    Size   File system  Name                  Flags
 1      1049kB  525MB  524MB  fat16        EFI system partition  boot, esp
 2      525MB   256GB  256GB               Linux filesystem

(parted) resizepart
Partition number? 2
End?  [512GB]? '100%'

(parted) print
[...]
Number  Start   End    Size   File system  Name                  Flags
 1      1049kB  525MB  524MB  fat16        EFI system partition  boot, esp
 2      525MB   512GB  512GB               Linux filesystem

(parted) q
  1. Boot machine from a bootable USB linux system (Arch Linux-, Ubuntu or similar USB installer)
  2. Open and resizing the encrypted LUKS volume
cryptsetup open /dev/sdb1 sdb1_crypt
cryptsetup resize sdb1_crypt
  1. Resize the physical device
pvresize /dev/mapper/sdb1_crypt
  1. Resize the logical device
lvextend -l +100%FREE /dev/mapper/vg-root
  1. Resizing the file-system of the volume
resize2fs /dev/mapper/vg-root
  1. Reboot. You are done.