How can you access the value of the ipaddress fact within a manifest?

Accessing the value of the ipaddress fact within a manifest can be done using either the fully qualified variable format or the simplified variable format.

Using the syntax $::ipaddress accesses the fact at the global scope, ensuring that it references the system's ipaddress fact regardless of the current scope of variables. This can be particularly useful in complex manifests where variable scopes may lead to confusion or conflicts.

On the other hand, using $ipaddress accesses the ipaddress fact directly without the namespace resolution. This is a shorthand notation, and Puppet recognizes it as a valid reference to the ipaddress fact.

Thus, both $ipaddress and $::ipaddress can be utilized effectively within a manifest, allowing for flexibility based on the context of the code and the specific needs of the manifest. The use of $facts['ipaddress'] is also valid but represents a slightly different approach involving the facts hash, which may not be as commonly used for simple access in newer Puppet practices.