We have seen/heard many people trying to move virtualized Linux servers from Xen to VMware and having issues. After some work ourselves we have found a way to do this and the solution is simpler than anticipated.

The reason for the complication is due to the Linux distribution changing the console type for Xen. In our view this is against the basis of virtualisation and it is meant to be almost the same as a hardware install. Normally Linux could use TTY but when Linux is installed on Xen it uses HVC0. This actually stops Linux from booting on anything other than Xen, which is kind of anoying.

So how do we move the guest OS in the first place? Well there are 2 ways:

  1. VMware standalone converter and use the P2V settings.
  2. In Xen export the VM in the Xen file format and then convert to VMware.

In my experience both are as good as each other. It is what you do after that which make the process work from a users perspective.

You can edit these options before you port them to VMware or have your machine ready to boot on the VMware platform. If editing once on VMware you need to have the console ready before you boot the Linux machine as you will need to edit the boot options. I won't go into what spacific button to press as each Linux distribution have their slight differences but as the grub loader appears you need to edit the boot commands. Once you are in the boot editor find "console=HVC0" and remove this line and then select boot. The machine will now boot fine and you will be presented with the normal screen.

To make these changes you will need to re-enable TTY again and edit the grub menu. There is plenty of documentation on how to do this for each Linux distribution as each one have their specifics.

I hope this helps you to get your machines ported, and if you are migrating services to Blue Sky Systems then we will take care of this for you anyway so you don't have to worry.