Puppet 4 :: Modules and Classes

Environments -> Modules -> classes -> parameters -> Inheritance -> Custom Resources

Environments & Modules

• Env: Support for Production and Development Code
• Env: puppet config print environment
• Env: Support for Isolation of Departmental Code
• Env: puppet config print environmentpath
• Env: Helps in using different versions of the module for each environment
• Module: Can be located in either the environment directory or a common shared directory
• Create environment in /etc/puppetlabs/code/environments/dev/{modules,manifests}
• Install module as follows puppet module install ntp --environment dev
• Module: To see the list puppet module list --environment dev
• Puppet configuration /etc/puppetlabs/puppet/puppet.conf
• To work under a environment puppet config set environment dev

Modules

• Puppet module is simply a directory tree with specific and predictable content
• Module contains
  • Name (ntp/)
    • manifests/init.pp
    • files/
    • lib/ # can contain facts
    • facts.d/ # external facts
    • templates/ # erb (embeded ruby file) | Puppet4 -> epb (embeded manifest file)
    • examples/
• manifest must contain a class with the same name as the module
• Modules Metadata
  • we can use puppet module generate skota/test # test = module name, skota = user name/ org name
    • this will start an interview process to collect other information i.e, version no, author etc..
  • To skip all we can use puppet module generate skota/test --skip-interview - This will use the defaults
  • stores data in metadata.json
  • This will help us in versioning our Modules
• tree module will list down the file structure

Sub Classes

ntp/manifests/config.pp    # create a file name under module's manifest folder

class ntp::config {        # class name should be prefixed by base class as shown (ntp::)
}

include ntp::config                # usage 1
notify => Class['ntp::config']     # usage 2