after updating all Enterprise components from 11.1 to 11.3 I'm seeing this in the Portal logs.
Error before stopping configuration observer. C:\arcgisportal\content\items\portal\portal-config.properties (The system cannot find the path specified)
What's odd is that our content directory is: E:\arcgisportal\content
And, "portal-config.properties" file is missing from both C: and E:
When the upgrade was progressing through steps 1-7 initially it failed, because of a disk space issue. After that was increased, Retry upgrade worked without issue.
The map viewer is missing all the layers, and details on the left-hand pane also. Otherwise, everything seems to be working fine. License.json imported from My ESRI, no other issues; all Enterprise components successfully updated.

Help, please!