====== Puppet ======
  * [[http://xiaopei.li/wiki/doku.php?id=it:puppet&s%5B%5D=puppet | Xiaopei Li's wiki page]]
  * [[http://wiki.m371n.org/doku.php?id=operation_maintenance:puppet:start&s%5B%5D=puppet | Merlin Dou's wiki page]]
  * [[https://puppetlabs.com/ | Official site]]
  * [[https://docs.puppetlabs.com/references/ | Official references]]
  * [[https://docs.puppetlabs.com/learning/ral.html | Learning Puppet — Resources and the RAL]]
  * [[https://docs.puppetlabs.com/guides/faq.html | Official FAQ]]
===== facter =====
  * [[http://kisspuppet.com/2014/03/30/puppet_learning_base10/| 自定义fact实现的四种方式介绍]]
====  Learning Puppet 笔记 ====
=== Resources and the RAL ===
  * ** Resources**: Imagine a system’s configuration as a collection of many independent atomic units; call them “resources.”
         * 资源可分类
         * 资源类型描述抽离于它的具体操作步骤
         * Puppet 指定资源的期望状态，而不是直接指定具体操作
         * 以上三点组成 Puppet 的资源抽象层 （RAL）， RAL 包括 **types**（高级别抽象模型） 和 **providers**（平台相关实现），这样可以使用平台无关的方式来描述资源得期望状态。
  * 每个资源（Resource ）的描述包括： **resource type**, one** title**, a number of **attributes**, each attribute has a **value** <code>
    user { 'dave':
      ensure     => present,
      uid        => '507',
      gid        => 'admin',
      shell      => '/bin/ksh',
      home       => '/home/dave',
      managehome => true,
    }
 </code>This syntax is called a **resource declaration**
  * Resource Types : [[https://docs.puppetlabs.com/puppet_core_types_cheatsheet.pdf | puppet_core_types_cheatsheet.pdf]], [[https://docs.puppetlabs.com/references/latest/type.html|the type references]]
  * ''puppet describe'' : The ''puppet describe'' subcommand can list info about// the currently installed resource types// on a given machine. 
  * ''puppet resource'': Puppet includes a command called ''puppet resource'', which can interactively inspect and modify resources on a single system. Usage:<code>
# puppet resource <TYPE> [<NAME>] [ATTRIBUTE=VALUE ...]
</code>
=== Manifests ===
  * ''.pp'': Puppet programs are called “manifests,” and they use the ''.pp'' file extension.
  * 完整语法链接：[[https://docs.puppetlabs.com/puppet/latest/reference/lang_resources.html| lang resources]]
        * 大括号，冒号，逗号要正确
        * 大小写敏感。 类型（type）和属性（attributes）名必须小写
        * 字符串值的书写: [[https://docs.puppetlabs.com/puppet/latest/reference/lang_datatypes.html| datatypes]]
        * All types have a special attribute called the **namevar**, 该属性缺失就默认以** title** 替代
  * Before being applied, manifests get compiled into a document called a **catalog**
  * ''puppet apply  <.pp file >''  
  * **Puppet agent/master**
=== Resource Ordering ===
  * You can embed relationship information in a resource with the ''before'', ''require'', ''notify'', and ''subscribe'' metaparameters.
  * You can also declare relationships outside a resource with the ''->'' and ''~>'' chaining arrows.
  * Relationships can be either ordering (this before that) or ordering-with-notification (this before that, and tell that whether this was changed).
  * Puppet’s relationship behaviors and syntaxes are documented in[[https://docs.puppetlabs.com/puppet/latest/reference/lang_relationships.html| the Puppet reference manual page on relationships]].
  * The ''ordering'' setting in ''puppet.conf'' determines the order in which unrelated resources are applied.
=== Variables, Conditionals, and Facts ===
  * Variables: 语法类似 php, 但实际是常量，只能被赋值一次， 不能修改。
  * Conditionals: ''if'', ''elseif'', ''else'', ''case'',''default''
  * Puppet has a bunch of built-in, pre-assigned variables that you can use.
  * Facts: [[https://docs.puppetlabs.com/puppet/latest/reference/lang_variables.html#facts-and-built-in-variables|facts]] ,Puppet uses a tool called Facter, which discovers some system information, normalizes it into a set of variables, and passes them off to Puppet. Puppet’s compiler then has access to those facts when it’s reading a manifest.
       * [[https://docs.puppetlabs.com/facter/latest/core_facts.html|List of core facts]]
       * [[https://docs.puppetlabs.com/facter/latest/custom_facts.html|The custom facts guild]]
=== Modules and Classes ===
  * Classes are named blocks of Puppet code, which can be created in one place and invoked elsewhere. 
  * Puppet 的 class 更像是宏， 但拥有变量域。
  * ''include <class name>'' 来起作用。
  * Modules: 
      * Modules are just directories with files, arranged in a specific, predictable structure. The manifest files within a module have to obey certain naming restrictions.
      * Puppet looks for modules in a specific place (or list of places). This set of directories is known as the ''modulepath'', which is a [[https://docs.puppetlabs.com/references/stable/configuration.html#modulepath|configurable setting]]
      * If a class is defined in a module, you can declare that class by name in //any manifest//. Puppet will automatically find and load the manifest that contains the class definition.
      * 一个 module 就是一个路径， 模块名就是路径名 
      * module layout: 模块包含子文件夹''manifests'',''files'',''templates''等等, 详看[[https://docs.puppetlabs.com/puppet/latest/reference/modules_fundamentals.html| a page of info about module layout]] 以及 [[https://docs.puppetlabs.com/module_cheat_sheet.pdf| module cheat sheet]].
      * module 静态文件(''files/''下)的引用格式: <code>puppet:///modules/模块名/文件名(可包括files下的子路径)</code>例如:<code>puppet:///modules/ntp/config_files/linux/ntp.conf.el</code>引用''ntp''模块下的''files/config_files/linux/ntp.conf.el''文件.
  * **puppet.conf**: The Puppet config file is called **puppet.conf**, and in Puppet Enterprise it is located at ''/etc/puppetlabs/puppet/puppet.conf''
  * The format of **puppet.conf** is explained in [[https://docs.puppetlabs.com/puppet/latest/reference/config_file_main.html|the configuration docs]]
  * [[http://forge.puppetlabs.com/|Puppet Forge]]: 模块仓库. 使用方式:install module:<code>$ sudo puppet module install puppetlabs-mysql//forge 里模块名有用户名前缀 </code> List all installed modules:<code>$ sudo puppet module list</code>
=== Templates ===
  * Templates are saved as files with the ''.erb'' extension. and be stored in the ''templates/'' directory of any module. There can be any number of subdirectories inside ''templates/''.
  * Use a template by the function ''template'': <code> file {'/etc/foo.conf':
  ensure => file,
  require => Package['foo'],
  content => template('foo/foo.conf.erb'),
}</code>''template''参数格式为''<MODULE NAME>/<FILENAME INSIDE TEMPLATES DIRECTORY>''.
  * Use a template by the function ''inline_template''