We have two virtual machines. The first is a Windows VM, where the ArcGIS server and the portal are installed (together with Web Adaptors on IIS) and the second is a Linux VM only with the Data Store (relational). I tried to upgrade our portal from version 10.7 to 10.8 and almost everything went well, but at the end, after submitting the Data Store configuration form, I get the following error:
"Attempt to configure data store failed. Caused by: Could not recover data store machine. Caused by: Attempt to configure data store failed. Caused by: Database upgrade failed for relational data store. Caused by: Upgrade from '10.6' to '10.10' is not supported."
What could have caused that error?