suggestion: rescue boot extension

[Richard W.M. Jones]

On Wed, Jun 02, 2010 at 03:13:21PM -0500, Eric Sandeen wrote:
> Jon Masters wrote:
> > On Wed, 2010-06-02 at 13:03 -0700, Roland McGrath wrote:
> >>> Hm. I can see the use of this, but I can also see issues with how you
> >>> do updates for it sanely (if at all.)
> >> Why would you do updates for it?  Your install CD/DVD to use for rescue
> >> boot doesn't get updated.  I'd think you'd just install a pristine newer
> >> one verbatim if you had a reason to bother, like deciding to burn a new CD.
> >> Hence the nice automagic deployment feature would reserve two partitions
> >> (or whatevers) for the purpose, so you can install the new image on B and
> >> still have the option to boot A if the new one is bad.
> > 
> > So I'm willing to help out on this (once RHEL stuff calms down a bit).
> > Do you think it's worth us putting together a wiki feature proposal?
> > 
> > Jon.
> > 
> > 
> 
> Is it better to have a separate volume for this, or to just have a sort
> of rescue initramfs ...?

Or if you are able to run a little bit of C code[1] and can read files
from the root partition (as grub can), you can build one on the fly
using binaries, libraries etc found on the root disk, which is what we
do in libguestfs.

Rich.

[1] http://git.annexia.org/?p=febootstrap.git;a=blob;f=febootstrap-supermin-helper.c;hb=HEAD

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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