Accessing facts from Puppet code

Using the $facts['fact_name'] hash syntax

Alternatively, facts are structured in a $facts hash, and your manifest code can access them as $facts['fact_name']. The variable name $facts is reserved, so local scopes cannot re-use it. Structured facts show up as a nested structure inside the $facts namespace, and can be accessed using Puppet's normal hash access syntax.

For example:

if $facts['os']['family'] == 'RedHat' {
  # ...
}

Accessing facts using this syntax makes for more readable and maintainable code, by making facts visibly distinct from other variables. It eliminates confusion that is possible when you use a local variable whose name happens to match that of a common fact.

Because of ambiguity with function invocation, the dot-separated access syntax that is available in Facter commands is not available with the $facts hash access syntax. However, you can instead use the get function built into core Puppet. For more information, see README.

Improving performance by blocking or caching built-in facts

If Facter is slowing down your code, you can configure Facter to block or cache built-in facts. When a system has a lot of something — for example, mount points or disks — Facter can take a long time to collect the facts from each one. When this is a problem, you can speed up Facter ’s collection by configuring these settings in the facter.conf file:

• blocklist for blocking built-in facts you’re uninterested in.

• ttls for caching built-in facts you don’t need retrieved frequently.