Arch Linux

Viaken

Member

Registered: 2008-06-26

Posts: 14

btrfs + LUKS + usb booting = mess [SOLVED]

Ok, so maybe I'm reaching a bit too far for current development. I just couldn't help myself. The transparent compression of btrfs seems ideal for a thumbdrive install, and if I'm going to be working from this thing, it seems prudent to make it a bit difficult to get to my data...

So far, this is where I'm at. I setup the LUKS partition and formatted it btrfs, put /dev/mapper/root in /etc/fstab with the compress option, and rebooted.

First hiccup seemed to be the one described in this bug: http://bugs.archlinux.org/task/11571

Basically, the device nodes don't exist when it tries to unencrypt, so I added the sleep in the hook as suggested.

The next issue seemed to be that /dev/disk/by-uuid/ wasn't working with the kernel root= option. I'm still not sure why this is the case, so I tried "root=/dev/sdf2" and got it to ask for the password. Success!

Except btrfs wasn't autodetected. Went back, "root=/dev/sdf2 rootfstype=btrfs" and it loaded the module correctly.

Now, it doesn't seem to want to use that as the root filesystem.

I'll be trying UUID= next boot and if need be, I'll remove the encryption and try booting to plain btrfs, but it should be possible based on what I'm seeing...

Feel free to share any insight of feedback on the process...

Last edited by Viaken (2009-05-07 13:13:53)

Viaken

Member

Registered: 2008-06-26

Posts: 14

Re: btrfs + LUKS + usb booting = mess [SOLVED]

Correction: I'd tried /dev/sdf2 after changing the hook as suggested...

/dev/disk/by-uuid does work, but I still get "Cannot mount root device (254,0)" "Cannot find init" on boot.

Viaken

Member

Registered: 2008-06-26

Posts: 14

Re: btrfs + LUKS + usb booting = mess [SOLVED]

So, I removed LUKS and made it a plain (but compressed) btrfs partition. Still had to use rootfstype, and this time I got an error regarding the loading of the btrfs module. "Unknown symbol crc32c", even though I implicitly included libcrc32c in the module list. I'm thinking this may be a bug that needs to be reported. I'll have to do so in a bit.

Zariel

Member

Registered: 2008-10-07

Posts: 446

Re: btrfs + LUKS + usb booting = mess [SOLVED]

Are you using initramfs? I think latest BTRFS uses kernels crc32 now instead of its own, dont know if thats an issue

bender02

Member

From: UK

Registered: 2007-02-04

Posts: 1,328

Re: btrfs + LUKS + usb booting = mess [SOLVED]

So, I removed LUKS and made it a plain (but compressed) btrfs partition. Still had to use rootfstype, and this time I got an error regarding the loading of the btrfs module. "Unknown symbol crc32c", even though I implicitly included libcrc32c in the module list. I'm thinking this may be a bug that needs to be reported. I'll have to do so in a bit.

It might want crc32c module, not libcrc32c (EDIT: I might be wrong I'm not on custom kernel so I can't check.)

Last edited by bender02 (2009-05-06 20:38:20)

Viaken

Member

Registered: 2008-06-26

Posts: 14

Re: btrfs + LUKS + usb booting = mess [SOLVED]

IT WORKS! Don't have LUKS atm, but...it works! Geez...it was looking for the crc32c module. Thanks for the hint, bender02. That was a mess. At least I know it works, now.