Cause
Without the Server Hostname field filled in, a FireSIGHT Management Center (also known as Defense Center) tells the JDBC client that it has an address of localhost, or 127.0.0.1, which causes the connection to fail.
Solution
Step 1: Log in to your FireSIGHT Management Center where the JDBC is trying to connect to.
Step 2: Navigate to System > Local > Configuration.
Step 3: When the page loads, select Database on the left pane.
Step 4: Ensure that the Server Hostname field is filled out with the Fully Qualified Domain Name, or the IP address of the FireSIGHT Management Center.