I messed it up.
Initially (+1 year ago), I installed oC 8.0.4 via opensuse feed on Ubuntu 14.04 server. All worked fine. Now I tried to upgrade to 8.2.1 using the web interface upgrade interface. Step 1-3 went fine, but the database (mysql) upgrade failed. Meanwhile I believe the entire /var/www/owncloud content seems messed up.
Bottomline, I like to install latest 9.1 now. However I don't really know which version was last installed since I did a couple of upgrades already after initial installation (8.0.4). config/config.php says 'version' => '188.8.131.52'.
Now ... how can I install install 9.1 and migrate/upgrade the database from 184.108.40.206 to 9.1?