jamesvoong@igloo:~$ lsblk
NAME                       MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
loop0                        7:0    0    13M  1 loop  /snap/gnome-characters/139
loop1                        7:1    0  34.6M  1 loop  /snap/gtk-common-themes/818
loop2                        7:2    0   2.3M  1 loop  /snap/gnome-calculator/260
loop3                        7:3    0    91M  1 loop  /snap/core/6350
loop4                        7:4    0 140.7M  1 loop  /snap/gnome-3-26-1604/74
loop5                        7:5    0  14.5M  1 loop  /snap/gnome-logs/45
loop6                        7:6    0   3.7M  1 loop  /snap/gnome-system-monitor/57
loop7                        7:7    0  89.1M  1 loop  /snap/core/8039
loop8                        7:8    0  54.5M  1 loop  /snap/core18/1265
loop9                        7:9    0   3.7M  1 loop  /snap/gnome-system-monitor/111
loop10                       7:10   0   956K  1 loop  /snap/gnome-logs/81
loop11                       7:11   0   4.2M  1 loop  /snap/gnome-calculator/544
loop12                       7:12   0  44.2M  1 loop  /snap/gtk-common-themes/1353
loop13                       7:13   0 140.7M  1 loop  /snap/gnome-3-26-1604/98
loop14                       7:14   0  14.8M  1 loop  /snap/gnome-characters/367
loop15                       7:15   0 156.7M  1 loop  /snap/gnome-3-28-1804/110
sda                          8:0    0 931.5G  0 disk
├─sda1                       8:1    0   512M  0 part  /boot/efi
├─sda2                       8:2    0   732M  0 part  /boot
└─sda3                       8:3    0 930.3G  0 part
  └─sda3_crypt             253:0    0 930.3G  0 crypt
    ├─ubuntu--vg-root      253:3    0 929.3G  0 lvm   /
    └─ubuntu--vg-swap_1    253:4    0   976M  0 lvm   [SWAP]
sdb                          8:16   0 119.2G  0 disk
└─sdb1                       8:17   0 119.2G  0 part
  ├─vg--pickle--ssd-swap   253:1    0   7.5G  0 lvm
  └─vg--pickle--ssd-docker 253:2    0 111.8G  0 lvm
jamesvoong@igloo:~$ sudo cryptsetup luksDump /dev/sda3
LUKS header information for /dev/sda3

Version:       	1
Cipher name:   	aes
Cipher mode:   	xts-plain64
Hash spec:     	sha256
Payload offset:	4096
MK bits:       	512
MK digest:     	dd dc 08 35 18 c5 8a ba 85 3f c2 07 aa 4a 9c 8b 51 4a 96 11
MK salt:       	f4 44 1c 7e 02 ab 69 5b f3 06 56 9e 93 80 d2 63
               	a4 6e 46 4b 28 0d 3d 57 d0 48 25 47 98 1d bb e9
MK iterations: 	99902
UUID:          	ba1fd4c4-8b87-4ead-bd19-8f43f8f70cf8

Key Slot 0: ENABLED
	Iterations:         	1598438
	Salt:               	42 c4 84 3c 3d 2e 71 d9 10 00 61 f4 67 07 b7 5b
	                      	7d f9 37 bc 8a 1e 5a 44 19 ef 55 97 20 c4 3a c5
	Key material offset:	8
	AF stripes:            	4000
Key Slot 1: DISABLED
Key Slot 2: DISABLED
Key Slot 3: DISABLED
Key Slot 4: DISABLED
Key Slot 5: DISABLED
Key Slot 6: DISABLED
Key Slot 7: DISABLED
jamesvoong@igloo:~$ cryptsetup luksAddKey /dev/sda3
#Device /dev/sda3 doesn't exist or access denied.
jamesvoong@igloo:~$ cryptsetup luksAddKey /dev/sda3
Device /dev/sda3 doesn't exist or access denied.
jamesvoong@igloo:~$ sudo cryptsetup luksAddKey /dev/sda3
Enter any existing passphrase:
No key available with this pass-phrase.