DevOps: Puppet, Docker, and Kubernetes

Passing parameters from Hiera

Like the parameter defaults we introduced in the previous chapter, Hiera may be used to provide default values to classes. This feature requires Puppet Version 3 and higher.

Getting ready

Install and configure hiera as we did in Chapter 2, Puppet Infrastructure. Create a global or common yaml file; this will serve as the default for all values.

How to do it...

1. Create a class with parameters and no default values:

   t@mylaptop ~/puppet $ mkdir -p modules/mysql/manifests t@mylaptop ~/puppet $ vim modules/mysql/manifests/init.pp
   class mysql ( $port, $socket, $package ) {
     notify {"Port: $port Socket: $socket Package: $package": }
   }
   

2. Update your common .yaml file in Hiera with the default values for the mysql class:

   ---
   mysql::port: ...