Parameters

Parameters are name-value pairs. The name of a parameter may not contain white space. The value may contain arbitrary Unicode strings. That way, entire scripts can be contained within parameters.

Parameter values can also be set to be hidden within the management UI. Note that a user with sufficient privileges can undo this.

The orcharhino interface also includes a text editor for creating and editing parameters. It shows the difference between your current changes and the previous parameter value, supports syntax highlighting, as well as Vim and Emacs like key bindings.

There are various types of parameters, which are restricted to different scopes, as well as organized into a parameter hierarchy. This means that if the same parameter is defined within multiple scopes, the value of the more restrictive scope will override the more general one. That way, for example, a globally defined fallback value, could be overridden for an individual host.

The full list of different parameter types, from highest to lowest priority, goes as follows:

The best practice recommendation is to use as restrictive a scope as possible (without needlessly proliferating duplicate parameters). Global parameters should remain the exception (for when you really need some value for every host).

The following table provides an overview of the different parameter types, as well as where to find them in the management UI: