localhost or mysql2.ibiblio.org?

Setting up a MySQL DB. I have user/password/db name but using localhost doesn’t work for the host. I checked another DB I have set up and it’s using mysql2.ibiblio.org. Is this what I should use for my westphotosdb database, or is there a different host name I should be using? Thank you!

For me (and others) to not be confused later, this was handled out of band. We provided a file that had database credentials in the home directory on the login host.