Resize LUKS LVM2 partition

Software & Operating Systems Linux
1

I want to decrease the size of an encrypted lvm partition, but 100% of the space is used. How do I figure out where the junk data is and resize the partition.

2

if theres no space in the volume group… you can add another another physical volume to grow the space… or you could get a larger physical volume to migrate all your LVs to, then reinstall the boot loader on the new physical drive.

3

No, its a 500GB drive with only 100GB used. LUKS writes junk data to the unused space as an added security feature, and I cannot figure out how to map it. Even after the LUKS is opened.

4

post the output from

vgs

lvs

dmsetup ls

df -h

lsblk

5 
pop-os@pop-os:~$ sudo lsblk    
NAME                MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
loop0                 7:0    0   2.1G  1 loop  /rofs
sda                   8:0    1  14.6G  0 disk  
├─sda1                8:1    1   2.3G  0 part  /cdrom
├─sda2                8:2    1     4M  0 part  
└─sda3                8:3    1  12.3G  0 part  /var/crash
nvme0n1             259:0    0   477G  0 disk  
├─nvme0n1p1         259:1    0   498M  0 part  
├─nvme0n1p2         259:2    0     4G  0 part  
├─nvme0n1p3         259:3    0 468.5G  0 part  
│ └─nvme0n1p3_crypt 253:0    0 468.4G  0 crypt 
└─nvme0n1p4         259:4    0     4G  0 part
pop-os@pop-os:~$ sudo lvs
LV   VG   Attr       LSize    Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
root data -wi------- <468.43g

pop-os@pop-os:~$ sudo dmsetup ls
nvme0n1p3_crypt	(253:0)

pop-os@pop-os:~$ sudo vgs
VG   #PV #LV #SN Attr   VSize    VFree
data   1   1   0 wz--n- <468.43g    0
6

if all the space was allocated, i dont know if you can shrink a luks volume.

might have to recreate it.

7 
pop-os@pop-os:~$ df -h
Filesystem                   Size  Used Avail Use% Mounted on
udev                         6.8G     0  6.8G   0% /dev
tmpfs                        1.4G  9.9M  1.4G   1% /run
/dev/sda1                    2.3G  2.3G     0 100% /cdrom
/dev/loop0                   2.2G  2.2G     0 100% /rofs
/cow                         6.9G  201M  6.7G   3% /
/dev/disk/by-label/writable   13G   47M   12G   1% /var/log
tmpfs                        6.9G     0  6.9G   0% /dev/shm
tmpfs                        5.0M     0  5.0M   0% /run/lock
tmpfs                        6.9G     0  6.9G   0% /sys/fs/cgroup
tmpfs                        6.9G  8.0K  6.9G   1% /tmp
tmpfs                        1.4G   44K  1.4G   1% /run/user/999

Booted into OS

username@pop-os:~$ df -h
Filesystem             Size  Used Avail Use% Mounted on
udev                   6.8G     0  6.8G   0% /dev
tmpfs                  1.4G  2.1M  1.4G   1% /run
/dev/mapper/data-root  461G   74G  364G  17% /
tmpfs                  6.9G     0  6.9G   0% /dev/shm
tmpfs                  5.0M     0  5.0M   0% /run/lock
tmpfs                  6.9G     0  6.9G   0% /sys/fs/cgroup
/dev/nvme0n1p1         498M  324M  174M  66% /boot/efi
/dev/nvme0n1p2         4.0G  2.3G  1.8G  57% /recovery
tmpfs                  1.4G   16K  1.4G   1% /run/user/110
tmpfs                  1.4G   28K  1.4G   1% /run/user/1000