Linux vs. Windows Live Conversion

I have been entrusted with converting a large number of Virtual machines that are currently hosted on Xen Server into the VMware Infrastructure.

There are all sorts of ways of migrating these a virtual machine exporting to VMDK's, Xen can export to a VMDK, convert to an OVF, other tools etc. I have found that the easiest way for the conversion is to treat the XEN VM as a live machine.

Besides all the different other lessons I am learning regarding the ins-and-outs of Xen Server  and their virtual machines, and all kinds of gotchas that you need to prepare for (look out for them in the upcoming blog posts). During the testing of the process, I noticed something quite interesting.

So the Xen VM is running either RHEL 4 / RHEL 5 / Windows XP / Windows 2003.

Importing Virtual machines directly with the vCenter Enterprise Converter is supports Windows targets only.

So in order to simplify the process and not have to use two different tools and procedures, I went with the vCenter Converter Standalone 4.0.1 for both flavors.

I will not put you through the steps on how to convert the live machine - you can actually refer to this post from a quite a while back.

Once the conversion starts - a new VM is created - as per your input, but this is where it differs.

A Linux conversion. The VM is powered on, connected to the network, booted with the helper ISO and the conversion begins. Creation of the partitions and copying them over one by one. Here are the screen shots of the converter and the details of the process in the vCenter as well.



And now a windows conversion. The VM is created but not powered on. The copy of the data actually takes place directly into the VM without having to use the Helper VM. Look at the screenshot below.


I find this quite interesting because I it seems that the conversion is occurring somehow in the background without having to use the helper VM. And even more so - if this can be done for a windows VM - why can this not be done also with a Linux VM?

I would be very interested in hearing if you have any more insight as to what happens in the background during the Windows Conversion.

Hope you enjoyed the ride.