XenServer to VMWware Migration

So I'm sure many of you have read all the tutorials and all the forums that say make sure to uninstall the tools before converting a VM from XenServer to VMware. Okay, so maybe they're right. If you want to cleanly move a Xen VM to VMware, then yes uninstall XenTools. However, if you want the converter to move a whole lot faster??????

DON'T UNINSTALL XENTOOLS!!!!

Ok, let's back up and explain why they say you should uninstall the tools. There's really only one primary reason for doing so...DRIVERS.  By uninstalling the tools, you force the VM to install the normal Windows drivers for the hardware and OS that it is sitting on. With the tools installed, you have all the Xen drivers which help it do things like Xenmotion or safely shutdown/restart the OS.

So I'm sure you are still waiting for me to tell you why you should actually keep XenTools installed on the VM. Well if you've ever used VMware Converter to convert a machine and you've uninstalled the tools, then you likely saw the migration dip to lightning speeds of 1KB/sec. On a VM with upwards of 100GB of data, you will be able to go get dinner, walk the dog, build 3 hosts, and possibly take a mini vacation before the VM is done. In the field, we saw a VM with about 500GB of data take a week to do the first initial synchronization and this was after it failed twice. The reason for the slowness is because the native drivers do not give the same speeds. In our environment, it was a difference between 100Mbps vs 1Gbps.

Are there any downsides? Well sort of. Initially, we would create a conversion job and set the job to not run the final synchronization. This would allow us to uninstall the tools right before the final synchronization job. However, this caused another problem later because the job would no longer start because it detected to many changes to the OS. So we tried not uninstalling the tools at all and just running the conversion all the way through with XenTools installed. What happened? Nothing but greatness. We were able to convert a 500GB VM from Xen to VMware in a matter of a few hours.

But things to note:

  1. Do not tell the conversion wizard to install VMware Tools.
  2. Do not install VMware Tools before uninstall XenTools.
  3. You MUST uninstall XenTools on the first boot of the VM otherwise you will get a BSOD (not the end of the world)
  4. You MUST uninstall all of the devices that are Xen related from Device Manager
    1. Open command prompt as administrator
    2. Type set devmgr_show_nonpresent_devices=1
    3. Type devmgmt.msc
    4. Show hidden devices within Device Manager
    5. Look for anything Citrix or Xen and remove.
  5. DO NOT REBOOT until you have removed all Xen items. If you do not, then you will get a BSOD (again not the end of the world)
  6. After you've removed all Xen items, then reboot and verify you don't get a BSOD (see what to do when you get a BSOD)
  7. Install VMware Tools
  8. Fix your network configuration
  9. Jump for Joy
So you got a BSOD? Well I did say that there was a sort of downside. Well the BSOD is the downside. However, it is easily resolved. Simply boot into safe mode and do all the things I stated in #4 of things to note. After you've done that, then you can reboot. And safely install VMware Tools. Fix your network configurations and yay you are done.

And yes, this can also work if you are running the conversion tool on the VM itself. Same process and in fact runs even faster than using a conversion server. Well that's all!!! Hopefully this saves you time.

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