Re: [dm-crypt] Encrypted root on Fedora 13

[Milan Broz <mbroz@redhat.com>]

On 10/25/2010 06:52 PM, Heinz Diehl wrote:
> is there any possibility in cryptsetup-1.1.3 to maintain / restore the uuid of an encrypted root
> partition on a Fedora 13 system? 

I think I added UUID into API (so you can specify UUID when formatting drive)
but I probably forgot to add it to CLI (cryptsetup binary) yet.

But there should be also way how to change it later.
(I saw that request for other things - like changing UUID of LUKS snapshot.)

If you want to track this, please add issue to cryptsetup page. I am just trying to
fix some long term requests for new release, this is one of candidates to fix.

But because UUID is encoded in header as string, you can probably
easily modify it using hexaeditor as workaround for now.

> I tried to chroot into the Fedora root directory from the boot CD and 
> rebuild the initramfs via dracut, but the root partition could not be
> found any more. I guess the uuid of the encrypted root partition is
> included in the initramfs, which means that I have to build an initramfs 
> from the active system, which isn't possible.

You can always extract initramfs, change it inside and compile it again.
(it is just cpio.gz archive)
(I have no encrypted fedora handy unfortunately to check whats needed.)

For now, I suggest to boot into dracut shell, activate system manually
(singleuser is ok) and recreate ramdisk.

see http://fedoraproject.org/wiki/Dracut/Debugging and
http://sourceforge.net/apps/trac/dracut/wiki/manpage

It should be 5 minutes job if you know how to do it:-)

Milan