$Id$

Background reading
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About Live CDs / livecd-creator tool:

  http://fedoraproject.org/wiki/FedoraLiveCD/LiveCDHowTo

The files in this directory
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livecd.ks.in

  Kickstart file which describes how to build the live CD.  This is
  essentially the configuration file for livecd-creator.  Most
  importantly it lists the RPMs which are needed on the live CD.

livecd-post.sh.in

  This is the %post-configuration section of the Kickstart script.  It
  is a shell script which runs after the RPMs have been installed but
  before the live CD is turned into an ISO.  The shell script creates
  any extra files we need on the live CD.

p2v.init

  This is installed on the live CD as /etc/init.d/p2v, and it causes the
  live CD to boot into the P2V configuration tool (see next).

virt-p2v

  This is the virt-p2v P2V configuration tool itself.  It is
  installed on the live CD as /usr/bin/virt-p2v and runs after the
  live CD has booted.  All the P2V stuff happens from this script. It
  uses the 'dialog' program to ask questions.

inittab

  Replacement /etc/inittab.

General implementation plan
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User boots the live CD.  The job of the live CD is to:

(a) Find local disks.

(b) Copy the disk image(s) over to the Xen host.

(c) Change certain files (eg. /etc/fstab may contain references to
disk devices, which need to be changed when running under Xen).

(d) BUT, the live CD must be totally non-destructive.  It cannot
modify the local disks in any way.

(e) The above steps are not automatic.  We need to ask the user some
questions along the way.

For (a) there are various methods to detect local devices.  We sniff
for devices in /sys/block.

For (b) we can simply use 'dd' and 'ssh'.  The general plan is to do
this:

  dd if=/dev/disk | ssh -C xenhost 'cat > /var/lib/xen/images/disk.img'

If the user doesn't have sshd installed on the Xen host, then they can
also opt for a pure TCP transport:

  dd if=/dev/disk | nc xenhost port

  and on the remote host they do:
  nc -kl port > /var/lib/xen/images/disks

For (c) we can use device-mapper snapshots to mount a ramdisk above
the disks themselves.  This allows us to make non-destructive changes
to files, and still see the "modified" block device (d).  A hairy
script looks for candidate files to modify.

Non-generic virt-p2v
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The above describes the generic virt-p2v, which asks users questions
after boot.  It is also possible to build your own live CD, based on
virt-p2v, which has various settings compiled in so it runs
automatically.