Fedora xen - Nov 2007 - Upgrading base Fedora installation with xen

I''m wondering if it would be possible to upgrade from one 
version of Fedora to another newer version using xen, 
without any down-time, apart from rebooting the machine to 
activate the new installation?

Something like this;

1) create a secondary linux root partition.

2) from the current active linux partition use xen to
    install the new version of Fedora on the secondary linux
    root partition.

3) compile and install any programs to /usr/local/xyz for
    the new kernel on the new linux root partition.

4) tweak and setup the new linux installation on the
    secondary partition, so it is ready to boot into.

5) reboot the machine so that the new Fedora root partition
    is now the active root partition.

So in theory, going from an older Fedora root partition, to 
a completely new installation of Fedora would only incurr 
the downtime of having to reboot the machine, into the ready 
and functioning new Fedora installation on the new root 
partition?

Is this possible, and has anyone tried it yet please?

I got as far a running xen on my machine OK, but KDE and X 
crashed when I tried to do anything else.

Kind Regards

Keith Roberts

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On 06/11/2007, Keith Roberts <keith@karsites.net>
wrote:
>
> I''m wondering if it would be possible to upgrade from one
> version of Fedora to another newer version using xen,
> without any down-time, apart from rebooting the machine to
> activate the new installation?

I''m not a Fedora expert (I''m from the Debian camp, where such
a question is
irrelevant :^), but I''m not sure that you need Xen to do this.

Instead, I''d look around for:

1. "yum --installroot...". That''s how I got a 64-bit Centos
4.4 running
under Xen under Debian. See
http://wiki.xensource.com/xenwiki/Centos4Yuminstallation

2. If jailtime.org has the version you want then download the image from
there, dump it on an LVM volume using "dd", mount it and tweak it to
boot
with the programs you want. You might be able to test it using Xen (or
Qemu?) before trying to boot it normally.

The idea is that you don''t have to hassle with setting up Xen just to
get
the installation process running - there could be simpler ways to get the
basic file system layout on your disk.

Cheers,

--Amos