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xulin

Member

Registered: 2026-01-16

Posts: 2

[SOLVED] LUKS decryption: asked for password twice

Reading the Wiki, and come across exactly to what I want to achieve, here: https://wiki.archlinux.org/title/Dm-cry … rase_twice
But, before I go ahead and do it, the part that is not clear is the bit about this entry:

# dd bs=512 count=4 if=/dev/random iflag=fullblock | install -m 0600 /dev/stdin /etc/cryptsetup-keys.d/cryptlvm.key
# cryptsetup -v luksAddKey /dev/sda3 /etc/cryptsetup-keys.d/cryptlvm.key

The "/dev/sdx" part. That's where I insert the drive where the whole partition resides, or where the unencrypted volume is?

zram0       swap        1     zram0 77fef2d3-a659-4c87-8838-6cf1880fb016                [SWAP]
nvme0n1                                                                                 
├─nvme0n1p1 vfat        FAT32       C25C-E100                                 2G     0% /efi
└─nvme0n1p2 crypto_LUKS 2           877b9f28-0226-4c4e-a7c1-c0749f4eee24                
  └─root    btrfs             ARCH  b0bc2f72-e11e-4c3d-a9d0-ba0db7dd3b5b  932.3G     2% /var/tmp
                                                                                        /var/log
                                                                                        /var/cache
                                                                                        /opt
                                                                                        /home
                                                                                        /

In my case, the SDX part would be "nvem0n1p2" correct? Making sure before I mess up my system
Appreciate all the help, and big thanks to the Arch Community!

Last edited by xulin (2026-01-19 17:33:05)

system72

Member

Registered: 2025-11-22

Posts: 542

Website

Re: [SOLVED] LUKS decryption: asked for password twice

looks like you should point it at the luks superblock, nvme0n1p2

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7712 0a9f 0e6b F099 091d  438b 8b38 5527 5dfd D001

xulin

Member

Registered: 2026-01-16

Posts: 2

Re: [SOLVED] LUKS decryption: asked for password twice

Thank you for the reply! I'll proceed per the wiki instructions now that it has been clarified