CIS 527 Spring 2015 Lecture 7

CIS 527

Lecture 7 - Puppet 1 - The Basics

Puppet

Learning Puppet

Much of this lecture's content is adapted from the Learning Puppet series on https://docs.puppetlabs.com/learning/

Learning Puppet VM

Follow along using the
Learning Puppet VM
http://puppetlabs.com/download-learning-vm
It is also available on the
CIS 527 transient drive

Abstraction

3 big insights

Similar resources can be grouped into types
Description can be separate from implementation
It is possible to declare a desired state for a resource

Resources

$> puppet resource service

Resources

$> puppet resource service

service { 'NetworkManager':
  ensure => 'stopped',
  enable => 'false',
}
service { 'acpid':
  ensure => 'running',
  enable => 'true',
}
service { 'anacron':
  ensure => 'stopped',
  enable => 'true',
}
...

Resources

A system is a collection of many resources
Each resource represents a small unit
Resources have a type, title and attributes

Resources Example

user { 'dave':
  ensure     => present,
  uid        => '507',
  gid        => 'admin',
  shell      => '/bin/zsh',
  home       => '/home/dave',
  managehome => true,
}

Find the type, title, attributes, and values

Resource Types

Package
File
Service
Notify
User / Group
Exec
Cron

Resource Reference

http://docs.puppetlabs.com/puppet_
core_types_cheatsheet.pdf

http://docs.puppetlabs.com/references/
latest/type.html

$> puppet describe <TYPE>

Modifying a Resource

$> puppet resource user russfeld
ensure=present shell="/bin/zsh"
home="/home/russfeld"
managehome=true

Modifying a Resource

$> puppet resource user russfeld
ensure=present shell="/bin/zsh"
home="/home/russfeld"
managehome=true

notice: /User[russfeld]/ensure: created
user { 'russfeld':
  ensure => 'present',
  home   => '/home/russfeld',
  shell  => '/bin/zsh'
}

Try to create your own user account

Manifest File

Defines a desired state for resources using a resource declaration
Can be applied repeatedly to the system
Can also contain logic and structural elements (next lecture)

First Manifest File

# /root/user-absent.pp
user {'russfeld':
  ensure => absent,
}

First Manifest File

# /root/user-absent.pp
user {'russfeld':
  ensure => absent,
}

$> puppet apply /root/user-absent.pp

First Manifest File

# /root/user-absent.pp
user {'russfeld':
  ensure => absent,
}

$> puppet apply /root/user-absent.pp

notice: /Stage[main]//User[russfeld]/
    ensure: removed
notice: Finished catalog run in
    0.44 seconds

Resource Declaration

file {'testfile':
  path    => '/tmp/testfile',
  ensure  => present,
  mode    => 0640,
  content => "I'm a test file.",
}

Type - file {
- Title - 'testfile' :
- Attribute/value pairs -
  ensure => present,
} (end of declaration)

Testing Resources

Run the manifest again
Delete /tmp/testfile
Change rights on /tmp/testfile
Change contents of /tmp/testfile

Manifest Compilation

Image Credit: Puppet Labs

Resource Ordering

# /root/training-manifests/2.file.pp

file {'/tmp/test1':
  ensure  => present,
  content => "Hi.",
}

file {'/tmp/test2':
  ensure => directory,
  mode   => 644,
}

file {'/tmp/test3':
  ensure => link,
  target => '/tmp/test1',
}

notify {"I'm notifying you.":}
notify {"So am I!":}

Resource Ordering

$ puppet apply /root/examples/file-2.pp
notice: /Stage[main]//File[/tmp/test1]/
    ensure: created
notice: /Stage[main]//File[/tmp/test3]/
    ensure: created
notice: /Stage[main]//File[/tmp/test2]/
    ensure: created
notice: So am I!
notice: /Stage[main]//Notify[So am I!]/
    message: defined 'message' as 'So am I!'
notice: I'm notifying you.
notice: /Stage[main]//Notify[I'm notifying you.]/
    message: defined 'message' as 'I'm notifying you.'
notice: Finished catalog run in 0.05 seconds

Resource Ordering

Puppet assumes resource declaraions are atomic
Therefore, it applies them in any order
You must define relationships between resources

Require

file {'/tmp/test1':
  ensure  => present,
  content => "Hi.",
}

notify {'/tmp/test1 has already been synced.':
  require => File['/tmp/test1'],
}

Before

file {'/tmp/test1':
  ensure  => present,
  content => "Hi.",
  before  => Notify['/tmp/test1 has
    already been synced.'],
}

notify {'/tmp/test1 has already been synced.':}

Subscribe

file { '/etc/ssh/sshd_config':
  ensure => file,
  mode   => 600,
  source => 'puppet:///modules/ssh/sshd_config',
}
service { 'sshd':
  ensure    => running,
  enable    => true,
  subscribe => File['/etc/ssh/sshd_config'],
}

Chaining Arrows

file {'/tmp/test1':
  ensure  => present,
  content => "Hi.",
}

notify {'after':
  message => '/tmp/test1 has already
    been synced.',
}

File['/tmp/test1'] -> Notify['after']

Chaining Arrows

file {'/tmp/test1':
  ensure  => present,
  content => "Hi.",
}
->
notify {'after':
  message => '/tmp/test1 has already
    been synced.',
}

Package/File/Service

package { 'openssh-server':
  ensure => present,
  before => File['/etc/ssh/sshd_config'],
}
file { '/etc/ssh/sshd_config':
  ensure => file,
  mode   => 600,
  source => '/root/examples/sshd_config',
}
service { 'sshd':
  ensure     => running,
  enable     => true,
  subscribe  => File['/etc/ssh/sshd_config'],
}

Assignments

Lab 2 - Configuration Management - Due Monday, Feb 23rd by 12:30 PM
Automate configuration using Puppet
Turn in:
- CIS Transient Storage
- via Storage Media in class Monday Feb 23rd