Why does the swap mapper file get created even though I removed it from /etc/crypttab?

Question

I have this line in /etc/crypttab for my swap partition:

luks-4205519b-f3fe-468f-b05e-44f25f6882a4 UUID=4205519b-f3fe-468f-b05e-44f25f6882a4     /crypto_keyfile.bin luks,keyscript=/bin/cat

I commented it out so it now looks like this:

# luks-4205519b-f3fe-468f-b05e-44f25f6882a4 UUID=4205519b-f3fe-468f-b05e-44f25f6882a4     /crypto_keyfile.bin luks,keyscript=/bin/cat

I rebooted but the mapper file /dev/mapper/luks-4205519b-f3fe-468f-b05e-44f25f6882a4 still gets created. Why?

Answer 1

You need to update your initramfs; there’s a copy of crypttab there.

On Debian derivatives, run

sudo update-initramfs -u