[dm-crypt] change passphrase

Biltong biltong at fastmail.fm
Tue Apr 1 21:02:42 CEST 2014

I have a raid-1 system running btrfs on top of luks.

I cannot remember my passphrase, but the system is running and I have
made a backup.

I'd like to add a new passphrase, and have followed the instructions
from 6.10 at

This worked for the first device, which seems to work with /dev/dm-0,
but I cannot work out what the device name for the second raid-1 member
is. The btrfs partition is on top of the luks device, and so I need to
change both.

The example shows:
  dmsetup table --target crypt --showkey /dev/mapper/c5

How do I know what to put in place of "/dev/mapper/c5"?

Many thanks.

  biltong at fastmail.fm

http://www.fastmail.fm - Send your email first class

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