It thinks that no TCP/IP port at the configured port on the configured machine is responding.
I don't know Oracle's setup, but for MS SQL Server, it's going to try and connect on port 1433 to whichever server you specify.
DBPing is a handy utility to
test to see if your setup is OK without things being confused by all the complex subsystems of the WebLogic Server, so if DBPing fails, check to make sure your port # is OK (check with the DBA to make sure that they didn't assign it to another port #) and that the server name was correctly supplied. You probably also need a valid database user ID and password.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.