###Note: We’ve released a major update to Hiera called Hiera 5.
It’s built into Puppet 4.9 and higher, and includes features like per-environment hierarchies, module data, simplified custom backends, improved debugging with
puppet lookup --explain, and more.
As part of this update, we’ve moved Hiera’s documentation into the Puppet reference manual. Once you’ve upgraded to Puppet 4.9 or higher, see the following pages for more info about the new Hiera:
Hiera is a key/value lookup tool for configuration data. Hiera makes Puppet better by keeping site-specific data out of your manifests. Puppet classes can request whatever data they need, and your Hiera data will act like a site-wide config file. Hiera 3 is compatible with Puppet 4; for Puppet 3.8 or earlier, use Hiera 1.