The following is the results of my lab environment’s upgrade of my first Hyper-V host from Windows Server 2012 to Windows Server 2012 R2. The following is the step-by-step experiences that I had upgrading my first host system to Windows Server 2012 R2.
To start the installation I mounted the ISO for Windows Server 2012 R2 and ran the installation as shown below.
It started by copying temporary files
Updates were added next
The default operating system version is Windows Server 2012 R2 Standard (Server Core Installation) but I still like my GUI so I chose the Windows Server 2012 R2 Standard (Server with a GUI) option.
The licensing agreement requirements were next.
And then the product key was required.
For my environment I wanted to do an upgrade to retain my existing configurations which I had for this Hyper-V server in my lab so I chose the upgrade option.
The compatibility report points out some key items including a required system reboot, and shutting down all virtuals on the system prior to upgrading.
After the reboot I saved the state for all running virtuals and re-ran setup. If I was doing this again I would have done a shutdown or preferably migrated off of each virtual and configured each virtual to not auto-restart on server reboot.
After the reboot and saving virtuals there were a few warnings: check for application compatibility, and virtual drive configuration.
During the installation as expected I lost connectivity during this timeframe via RDP setup screen was running when viewing the host system directly. After those portions of the installation were completed I was able to RDP back to the Hyper-V system which was upgraded.
The following shows the Hyper-V manager after successful upgrade to Windows 2012 R2!
Storage spaces and drives on the system were all still all in place and functional as expected after the upgrade.
I had problems which occurred when I attempted to re-start the virtuals (as referenced earlier I should have shut them down instead of saving them in their current state).
The virtual showed a configuration error related to the virtual switch on the virtual which gave me a hint as to the underlying issue.
The upgrade removed all of the virtual switch configurations which had been set on the Hyper-V host.
Summary: The upgrade from Windows Server 2012 to Windows Server 2012 R2 ran well in my environment with the one exception of the Hyper-V virtual switch configuration. These settings will need to be repopulated back over from SCVMM to the Hyper-V host and I hope to write a follow-up blog post on those steps. Additionally, I would recommend moving all virtuals from the host prior to upgrading the host.