[CentOS] Migrating standalone systems to xen guests

Fri Mar 4 12:58:30 UTC 2011
Simon Matter <simon.matter at invoca.ch>

> On Fri, Mar 4, 2011 at 4:57 AM, Simon Matter <simon.matter at invoca.ch>
> wrote:
>>> On Fri, Mar 04, 2011 at 10:31:18AM +0200, Jussi Hirvi wrote:
>>>> Is there any (easy?) way to migrate running standalone CentOS 4 or 5
>>>> systems to xen virtual stacks?
>>>>
>>>> Rebuilding those systems from scratch on the xen machine would take
>>>> plenty of work.
>>>>
>>>
>>> If you're talking about Xen PV domUs, then the process
>>> is pretty much like this:
>>>
>>> - ssh into the standalone system.
>>> - make sure /etc/modprobe.conf includes xenblk driver (so that it'll be
>>> included in the generated initrd when you install kernel-xen).
>>> - fix /etc/fstab to have xvd* (xen virtual disk) devices instead of
>>> sd*.
>>> - install kernel-xen rpm.
>>> - verify kernel-xen is the default in /boot/grub/grub.conf.
>>> - verify root= parameter is correct in /boot/grub/grub.conf for
>>> kernel-xen.
>>> - copy/transfer all the files from the standalone system to virtual
>>> disk/image.
>>
>> Make sure here to copy with preserving hardlinks, use tar or rsync -aH
>> for
>> this. And, you can exclude some content like /dev/* (but not the
>> directory
>> /dev itself!).
>
> Use "star". This will preserve SELinux configurations, which neither
> tar nor rsync do.

Ah, forgot about that, because I always disable SELinux - if I want it so
secure I'd take OpenBSD :)

Simon