When trying to set up an ESG (v7.6.2) to its remote SQL server, the field in TRITON says you can use the host name or the IP address.
In fact, when you're using a remote SQL server and Windows authentication, the ESG installation program for TRITON very nicely builds the correct ODBC connection and fills in the Log Database field in Email Security with the FQDN of the SQL server.
So it you're using "websensedb.sql1.example.local" as the remote SQL server, it very nicely prefills that in.
But it doesn't work. The ODBC connection passes its Connection Test satisfactorily but when you test the connection from the ESG it fails. Not only does the FQDN fail, so does just the host name. You MUST enter the IP address of the SQL server and then it works from the ESG immediately.
We use CNAMEs for all database connections. This lets us do DR faster because we just have to change one DNS entry. But in the ESG we must use the IP address even though the ODBC connection on the same server works fine by the fully qualified CNAME.