@Manfred_Wilhelm Welcome to the Rockstor community.
Your report is a little confusing as it points to a failed db migration when non have happened between 3.9.1-1 to 3.9.1-7. Could it be that you mean an upgrade from some version less than 3.8-14.3 to 3.9.1-7 (see later for details). You might find that a reboot will sort this however. If you paste the output of the following command run as root it should indicate what has been applied db migration wise (this will only work on more recent version of Rockstor):
/opt/rockstor/bin/django showmigrations
You may well find that a reboot will sort this as the db migration may sort itself out.
From:
relates to the following addition:
If you have in fact upgraded from such an old version (ie < 3.8.15) then if you find that a reboot does not sort your install out then you may want to take a look at the following post as in the mean time we have changed our database migration system; essentially if you were not running a stable subscritpion with auto update enabled you may have to have stopped off at 3.8.15 first.
The part that may apply to you is the heading:
“I have a broken system after upgrading to 3.8.16. What do I do?”
Obviously as that post is now quite old it would be better, if you are to take the alternative re-install route describe there, to use the latest iso which as of this post is 3.9.1.iso.
Hope that helps.