System Variables are about accessing data. They differ from Secured Variables in several ways:
System Variables are typically used in connections and feeds to help isolate system-specific environment settings. Administrators can set up variants of local.properties for Dev, QA, and Prod systems. They can be used directly when a Connection, Feed, or Transform property supports Expressions, and they can also be used inside of a Secured Variable or Credential when its default value is configured as an Expression rather than a Static Value.
The recommended way to set up System Variables is to declare the available System Variables in [Install_Home]/conf/custom.properties and override them as needed via [Install_Home]/conf/local.properties:
There are two types of System Variables: Standard sysVar and Encrypted encSysVar. The first ‘sysVar’ variable type is not encrypted, and the administrator can see the value when inserting it into an Expression. The second ‘encSysVar’ variable type is encrypted. When encrypted encSysVars are accessed, their values in the properties file will be encrypted if necessary. The encSysVar’s value will be displayed as a standard ‘****’ when inserting it into an Expression.