How to: Set a SQL Server Alias (SQL Server Management Studio)
This topic describes how to set a Microsoft SQL Server alias for SQL Server Agent to use to connect to the Database Engine. By default, the SQL Server Agent service connects to an instance of SQL Server over named pipes by using dynamic server names that require no additional client configuration. You need to configure a server connection alias only if you are not using the default network transport or if you are connecting to an instance of SQL Server that listens on an alternate named pipe.
In the Object Explorer, connect to an instance of the SQL Server Database Engine and then expand that instance.
Right-click SQL Server Agent, and then click Properties.
In the SQL Server Agent Properties dialog box, click Connection, and type the alias name in the Alias local host server field to which SQL Server Agent should connect.
SQL Server Agent will not work correctly unless you select an alias that refers to the local instance of SQL Server.