Facing issues with applying SP2/SP3 for SQL 2008 R2 FCI

One of my clients happened to encounter an issue upgrading the SQL server 2008 R2 instance from SP2 to SP3.

We were able to pass the major part of the wizard and at the final Installation Progress bar stage we faced issues and the upgrade failed for us with the below error recorded in the Summary logs

Final result:                  The patch installer has failed to update the following instance: <Instance Name >. To determine the reason for failure, review the log files.
Exit code (Decimal):           -568706566
Exit facility code:            1562
Exit error code:               14842
Exit message:                  The patch installer has failed to update the following instance: <Instance Name >. To determine the reason for failure, review the log files.
Requested action:              Patch

Instance <Instance Name> overall summary:
Final result:                  The patch installer has failed to update the shared features. To determine the reason for failure, review the log files.
Exit code (Decimal):           -568706566
Exit facility code:            1562
Exit error code:               14842
Exit message:                  Element not found. (Exception from HRESULT: 0x80070490)
Requested action:              Patch

In case of SQL fail-over cluster configurations which are not maintained wisely, these kind of scenarios are quite expected to occur. This issue is basically caused if we have any offline or removed disks as a part of the cluster which are no longer presented to the server nodes.

To resolve this, we have to run the Cluster validation report in which we will be observing the  " Element not found" error in Disk Configuration/ for storage validation tests. On identifying those disks we need remove/delete them from the cluster and re-run the Service pack media to fix the issue.

Hope this helps.. Happy Upgrading!!