This is not the answer to my problem.

I want that new visitors don't get redirected to /web/database/selector. 

It should be redirected to a db that is set as primary DB.

But when I tip in the URL /web/database/selector it should show me all my dbs that i have.

Don't work with that dbfilter, when I tip in web/database/selector it shows me only 1 database not all.

I want that when I tip web/database/selector it shows me all my database and when one visitor visit my site it goes to a random database, and not to the selector

Edit: Ok I found a way to clear my issue with Odoo 8 nginx. Contact me for Info.

Solution in Odoo config:

list_db=False