Sometimes you have an application and you don’t know what SQL Server it’s using and can’t log into the app to find out or don’t know where the configuration setting is for SQL to find out what sql server the application is using. Here’s how to find out what sql server an application is using:
Log onto the application server and run netstat -a in the command prompt. This will list a bunch of servers (and PCs) that have connections to the server. The likelihood is, that one of those computers listed is the SQL server the application server is using. It will probably even say that the type of port is SQL (ms-sql-s).