Also, as additional information that confirm the above approach.
Check the following quotes from SAP Note:
1494740 - SAP System Migration from Older Windows Releases to Newer Ones
" In-place upgrades on Microsoft Failover Clusters are not supported.
Microsoft does not support in-place upgrades from a Windows Server 2003 cluster (MSCS) to Windows Server 2008 Failover Cluster, or from any Windows Server that is part of a Failover Cluster.
Therefore, you cannot use the in-place upgrade for a high-availability SAP system on Windows."
AND
The following list shows some examples where you must perform a system copy and you cannot perform the Windows in-place upgrade.
- The hardware vendor does not support the Windows target release version.
- The database vendor does not support the Windows target release version.
- SAP does not support the SAP release on the Windows target release version.
- There is no downtime time slot to do a Windows in-place upgrade.
- For your productive system only short downtime periods are allowed, which might be exceeded when performing the in-place upgrade.
- You run an SAP system with Microsoft Failover Cluster.
- You use incompatible third-party applications or system drivers.
- You use Windows on Itanium servers (IA64).