[TriLUG] Booting LUKS

[Brian McCullough]

On Sat, Jun 30, 2012 at 03:50:32PM -0400, Brian McCullough wrote:
> Back at the beginning of the month, I had a conversation with Alan
> Porter about the issues when trying to boot multiple versions of Linux
> and possibly other operating systems on a single machine.
> 
> Since then, I have discovered an interesting concept, and tool, called
> dracut, which is intended to create a much smaller initial ramdisk, only
> containing the drivers and other components necessary to give the kernel
> access to the proper root file system.  Once that has been accomplished,
> control transfers to the main system, and life goes on.
> 
> At least that's how I understand dracut.
> 
> 
> On to the questions, at least the first couple.
> 
> 
> Has anybody else encountered, and preferably used, dracut?

I gather from the lack of response that nobody else has dealt with
Dracut.


According to the documentation that I have found, including the man
pages that ship with the Debianish package, this is really intended to
operate in a Red Hat-like environment.  The Debian or Ubuntu version is
stale, approximately two years out of date, and doesn't seem to work
properly in this environment, particularly when dealing with a LUKS
disk.  I will try creating a non-LUKS OS install and see if I can get
Dracut working there, but that isn't really what I am trying to use.


Are there any other tools out there that might do this sort of task?


Of course, there is mkinitrd, mkinitramfs, but also yaird and dracut.
The last seems to be in current development and well-liked in the Red
Hat world, but not adapted to Debian environments at the moment.


It appears, by changing my search terms, that in the Debianish world,
initramfs-tools is considered the correct tool for any purpose, at
least as far as initramfs is concerned.  Perhaps I need to learn how to
build a more generic, smaller, simpler, initramfs using initramfs-tools,
instead of looking for a different tool.



As the old joke goes about alligators and swamps, my original goal was
booting two different Ubuntu variants, with independent LVM Root
partitions, in a LUKS-encrypted whole disk.  With the default
installation script, I can only boot into the last one installed,
because it appears that the initramfs has the LVM Root Partition's name
bound into it, rather than just getting the system running, and using
the /etc/fstab that is on that Root partition.  The Root Partition's
name is passed in on the Kernel command line, but that seems to get
ignored.



Thanks,
Brian