Throughout TrueSight Server Automation, an important use for properties is to create parameters, which are references to properties. For example, when you deploy an Apache server to Windows and UNIX platforms, you can specify a different installation directory for each platform by defining a server property that might be called
On Windows servers, this property might have a value of /c/Program Files/Apache. On UNIX servers the property might have a value of /usr/local/Apache.
In the BLPackage that encapsulates the Apache server, you can insert a parameter that refers to
APACHE_INSTALL_DIR. When that BLPackage is deployed to a server, TrueSight Server Automation obtains the server's value for
APACHE_INSTALL_DIR. Using a parameter in this way, you can deploy the same BLPackage to multiple servers running different OSs.
You can use parameters and properties in BLPackages, component templates, configuration files, and extended objects. Resolving a parameter to a property value happens at different times. For example, in a component template, a parameter might get resolved when you discover a component based on that template. For an extended object, a parameter could be used to identify content when you attempt to run a job based on the extended object. In all cases, however, the parameter serves as a reference to a property. The property value is determined when the parameter is processed.