Introduction to Puppet Scripting

Introduction to Puppet Scripting

• 1.
  Introduction to Puppet Scripting ShawnS. Smiley Lead Architect Achieve Internet shawn.smiley@achieveinternet.com
• 2.
  What is puppet? “Puppet is IT automation software that helps system administrators manage infrastructure throughout its lifecycle, from provisioning and configuration to patch management and compliance.” Source: www.puppetlabs.com/puppet/what-is-puppet
• 3.
  What does thatmean? • You can setup a new server in minutes vs. hours! • You can be sure your server configurations are consistent. • You can easily deploy configuration changes to multiple servers. Image Source: http://www.forbes.com/sites/kenkrogue/2012/09/07/the-most-important-interview-question-never-asked/
• 4.
  Quick Demo Image source:http://gyaniji.blogspot.com/2011/12/demo-of-ad-posting-job.html
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  What happened? • Puppetanalyzed the scripts to build a picture of what the server should look like. • Puppet then compared that to what the server actually looks like. • It then generates and executes scripts to make the server configuration match that in the puppet scripts.
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  How vs. What •Why is it better to describe what a system looks like rather than how to configure a system? • When you describe what a system looks like, you can repeatedly rerun the process without fear of breaking the system. • Can build platform independent scripts.
• 7.
  What are thepieces? • Puppet Software • Module Library • Node configuration file • [optional] Puppet Master
• 8.
  Modules What are they? •Self-contained packages that describe an aspect of a system (e.g. “Apache” or “MySQL”) Are there existing packages I can leverage? • http://forge.puppetlabs.com • http://github.com Where do I put them? • /usr/share/puppet/modules • /etc/puppet/modules
• 9.
  File Organization • manifests • site.pp • nodes.pp • modules • module1 • manifests  init.pp • files • templates • module2
• 10.
  Demo: Folder Structure Imagesource: http://gyaniji.blogspot.com/2011/12/demo-of-ad-posting-job.html
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  Basic Syntax • Followsbasic Ruby language syntax. • Does not fully implement the Ruby language though, only a subset is allowed in your puppet files. To define an item: To execute an item: type title($arg1) { include “title” description of resource state } type {“title”: } type {“title”: arg1 => ‘hello’ }
• 12.
  Demo: Simple script Imagesource: http://gyaniji.blogspot.com/2011/12/demo-of-ad-posting-job.html
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  Resource Types • Arepuppet libraries that are used to interact with the system. • Puppet comes with a wide range of resource types: • exec • package • file • service • notify Full list: http://docs.puppetlabs.com/references/latest/type.html
• 14.
  Facter What are facts? •Global variables with information about the system that the script is running on. How do I see the available variables? • facter -p How do I use them? • $::variable_name
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  Templates • Templates arefiles that use a simple markup language to insert dynamic values. • Templates have an .erb extension • Typically used with the File resource. e.g.: file {'ntp.conf': path => '/etc/ntp.conf', ensure => file, content => template('ntp/ntp.conf.erb'), owner => root, mode => 0644, }
• 16.
  Relationships • Package[“ntp”] ->File[„ntp.conf‟] ~> Service[„ntpd‟] • “before”, “require” • “subscribe”, “notify” http://docs.puppetlabs.com/puppet/2.7/reference/lang_relati onships.html#relationship-metaparameters http://docs.puppetlabs.com/puppet/2.7/reference/lang_relati onships.html#chaining-arrows
• 17.
  User-Defined Types • Similarto functions in most languages. • Only way to do iterations currently. • Call the Type with an array. define apache::vhost() { $docroot = “/var/www/${name}” } $sites = [‘site1’, ‘site2’] apache::vhost {$sites: }
• 18.
  References Books • Managing Infrastructurewith Puppet (ISBN: 978-1-4493-0763-9) • Pro Puppet (ISBN: 978-1-4302-3057-1) Websites • http://www.puppetlabs.com • http://docs.puppetlabs.com/ • http://forge.puppetlabs.com/
• 19.
  Q&A