Roles

Let's take another step back and consider what we want to achieve with the roles part of the pattern. The overarching task is to piece together these building-brick-like profile classes into full tech stacks, which we call roles, and are now the second part of our full pattern:

Here you can see that we have taken the composite profiles from our previous example, and stacked them one on top of the other, to produce a full tech stack. We are also utilizing two additional shared profiles:

• profile::base is included in all machines, including workstations. It manages security baselines and so on, using conditional logic for OS-specific profiles; for example, profile:: base::ubuntu, profile::base::redhat, and so on, as needed.
• profile::server is included in all machines that provide a service over the network, and configures services such as NTP, firewalls, monitoring, logging, and so on.

Let's look again at the fully functional LAMP stack as an example in Puppet DSL:

# LAMP stack


class role::lamp {
  include profile::web::apache
  include profile::db::mysql
  include profile::programming::php
  include profile::server
  include profile::base
}