Previewgenerator App 1.0.3 | Doctrine-DBAL-Exception-DriverException

After executing

        occ preview:pre-generate

i’ve got this error:

Now i am not able to call occ preview:pre-generate again, because it says:

        Command is already running.

But it isn’t, because

        ps ax|grep generate

does not return anything.

PS: Nextcloud 11.0.1 on Ubuntu 16.04.

Looks like it waits a fixed 30 minutes before letting you run it again. You can either wait it out (as you probably have by now) or, if you’re impatient (like me) and really sure it’s not running already, SELECT * FROM 'oc_appconfig' WHERE 'configkey' LIKE 'lastActivity' and delete that timestamp.