Portal for ArcGIS: Failed to start the database server. The startup timed out

Error Message

When upgrading Portal for ArcGIS, the upgrade process fails and returns the following error message:

Error:   
Failed to start the database server. The startup timed out. Please check the log file at D:\arcgisportal\logs\database\pgsql.log.

Cause

The machine hosting Portal does not have sufficient disk space available for the upgrade to be completed.

Solution or Workaround

Free up disk space on the machine to ensure that a minimum of 2.5 times the space allocated to the Portal content, index, database, and temporary directories is available. Refer to ArcGIS Enterprise on Windows and Linux: Prepare to upgrade for more information. The options below are applicable before upgrading Portal:

• Remove any temporary files in Portal. Refer to How To: Delete ArcGIS Enterprise temporary files for instructions.
• Identify and remove any large items in Portal. Refer ArcGIS Enterprise on Windows and Linux: Delete items owned by others for instructions.
• Relocate the Portal content and related directories to a drive with sufficient capacity and ensure permission remains correct for the Portal service account. Refer to ArcGIS Enterprise on Windows and Linux: Change the portal content directory for instructions.
• Delete or relocate the non-Portal files consuming the same disk space. Refer to Microsoft: Free up drive space in Windows for instructions.