In this blog, I have mentioned the the procedure involved in migrating a Windows 2008 R2 guest VM from Citrix XenServer to Red Hat Enterprise Virtualization (RHEV) platform. Basically its Xenserver v2v hence this method can be used for all V2V. Its rather safe method since there are no changes to the source VM. I have used the disk cloning method to transfer the VM from Citrix XenServer to Red Hat Enterprise Virtualization (RHEV) platform. However, after the VM is transferred to Red Hat Enterprise Virtualization (RHEV) platform, Windows Guest VM will intially throw Blue Screen error. I have mentioned the work around to overcome the blue screen error and then run the Windows Guest normally. The
tools used here clone is Clonezilla. Clonezilla live CD might
have a blank screen issue in Citrix XenServer hence, I have used Archlinux Live CD, which is bundled with Clonezilla.
The step-by-step procedure to convert a
Windows 2008 R2 guest VM from Citrix Xenserver to Red hat RHEV is as below.
Step 1: Download the Archlinux Live CD ISO image
and upload it into your XenServer ISO storage. Shut down the guest VM you want
to migrate and boot it using ArchLinux Live CD. If you don't have a ISO mount
created in XenServer, you may follow these steps to add it. Note: Please choose
"Boot Arch Linux (i686)" while booting. Booting into x86_64 might
fail or end up in blank screen.
Step2: Once booted into Live CD, type Clonezilla
and press enter. This will take you through disk cloning process. Follow these steps to create a clone image of your
windows guest. Skip the initial steps in the clonezilla guide and start from
'Choose "device-image" option'. It's too tedious map your image
external disk in the hypervisor and then mount it in Acrh Linux, so avoid using
local disk for storing image. Clonezilla gives you multiple options to store
image on the network. I chose ssh-server and saved it in RHEV Manager. It might
take several minutes to create image of your disk depending on how the size of
disk and the data inside.
Step3: Create a new VM in RHEV. Keep the guest
disk size as same as the source guest VM in XenServer. Ex:- If the disk that
you clone above is 500GB in size, create 500GB disk in the guest VM that you
create in RHEV.
Step4: Upload the same ArchLinux ISO image that
you have downloaded above to your ISO repository in RHEV. Select "Run
Once" and choose the ArcLinux ISO image and boot from it.
Step5: Once booted into Archlinux Live CD, type
Clonezilla and press enter. Follow these steps restore disk image created in step2 to
the guest VM newly created in step3. Skip the initial steps in the clonezilla
guide and start from 'Choose "device-image" option'. Choose the image
that your created in Step2 and restore it. It might take several minutes to
restore the image.
Step6: This step is important. After you restore
the image and boot Windows Guest in RHEV, it will throw Blue Screen. But dont
panic. It's just because the guest VM doesn't have VirtIO SCSI Drivers hence it
cant detect the Hard disk.
Now shut down the guest VM in RHEV. You
need to start the VM again by clicking on 'Run Once'.
Mount the 'virtio-drvers' floppy image.
Step7: Boot the guest VM into recovery mode using
"Launch Startup Repair". If you don't see the option then press
immediately F8 after POST and select "Repair Your Computer".
Once booted into recovery mode, select the
keyboard layout and click on next.
Step8: In the "System Recovery Options"
click on "Load Drivers".
Select the floppy drive and select
A:\amd64\Win2008R2\.
This will list all available drivers in
the floppy disk. Select viostore.inf
In the next screen, Choose "Red Hat
VirtIO SCSI Controller" and click on "Add Drivers...".
This should detect hard disk and show you
"Windows Server 2008 R2". Select Restore your computer ......."
and click "Next".
Next step will try to detect the system
restore image. Ignore the error and Click on "Cancel" to come out of
image restore process.
In the next screen, click on "Command
Prompt" to open command window.
Step9: In the command type 'diskpart' and press
enter. Then type 'list volume' to see the drive letter of your Windows Guest
Disk. In the below example the driver letter is C:\
Now you need to load the VirtIO drivers to
your Windows Guest. To do it, type the below command and press enter.
Dism /image:E:\ /Add-Driver
/driver:A:\amd64\Win2008R2 /recurse
You will see a success message once the drivers
are loaded into Windows guest.
Step10: Now exit from "Command Prompt"
and reboot Windows Guest VM. After reboot, boot the Windows Guest VM into
normal mode.
This workaround worked fine with my
environment. I had Windows 2008R2 guest VM with single disk of 100GB running on
Citrix XenServer 6.2. This procedural might work for V2V and P2V converstion
from any Virtualization Software to Red hat RHEV. This will might also work for
all other flavors of Windows 2008 and Windows 2012. You just need to change the
path of the drivers in the command in step9.
Please like my post if this helped you.
