Upgrade Windows 2008 R2 (with SQL Server and AD) to Windows 2012
I already realized various migrations of Windows 2008 R2 to Windows 2012, where he raises the C:\Windows.old folder with previous data and do I reconfigure the server, also called side-by-side upgrade.
Important: Verify applications in your Windows 2008 R2 have a update or compatible to Windows 2012. For example, Exchange 2012 and System Center 2012 not compatible yet.
Today I decided to do some testing in-place upgrade of Windows 2008 R2 to Windows 2012, direct with the machine in the air. The machine that migrated is a Domain Controller with the FSMOs and SQL Server 2008 R2 with Reporting Services to support my entire System Center 2012 lab.
The result was positive, the AD went up as expected, SQL Server 2008 R2 (which was updated) and the SRSS worked perfectly as shown in the print below:
And when something goes wrong?
This happened to me, in the middle of migration the external HD that I use for VMs lost connection. The installation was already on the third boot when it is carried out the migration of settings and restart the VM had access to this menu:
Chose the option Windows Setup Rollback and the result was exceptional. Windows 2008 R2 returned with all features running, as if nothing had happened and showed the message below:
Note that the SQL and the rest of applications continued running after the rollback, demonstrating the maturity of the in-place upgrade process available in Windows 2012.
Before upgrade in-place you need a backup (image) obviously, but put the upgrade of servers with Windows 2008 R2 SP1 to Windows 2102 as a safe and advantageous possibility!