Puppet_Intro_Installation.txt

Puppet
--->it is a configuration management tool available as open-source and Enterprise version.It runs on Unix like systems and Windows Systems.
--->Puppet is produced by Puppet labs founded by Luke Kanies in 2005.
--->It is written in Ruby and released as free software under GNU GENEREAL PUBLIC LICENSE until version 2.7.0 and Apache License after that.
--->Puppet is designed to manage the configuration of Unix-like and Microsoft windows.

How Puppet works
The information is stored in files called "Puppet manifests" with extension of ".pp".Puppet discovers the system information via a utility called Facter and compiles the puppet manifests into a specific catalog containing resources and resource dependencies which are applied against the target system. Any action taken by puupet are then reported.

Puppet Master
 it is the service runs on the main server which is used to manage the entire clients to deploy, configure and maintains the infrastructures.
Puppet Agent
  Puppet agent is a service runs on client which sends the request the catalog to puppet master and applies it by checking each resource the catalog describes. If it finds that any resource is not in the desired state, it makes the changes necessary to correct them.After applying the catalog, the agen submits a report Puppet Master.
Catalog
 it is a document that describes the desired state for one specific server. It lists all the resources that need to be managed, as well as dependencies between them.

Puppet agent nodes and Puppet master communicates via HTTPS with client verification.The Puppet master provides an HTTP interface with various end points are available. When requesting or submitting anything to master, the agent makes HTTPS request to one of the end points.

Manifests
 are the files with extension ".pp" where we declare all resources to be checked or to be changed. Resources may be files,packages etc

Resources Types
 A type of package or service or file or user or mount
 
Syntax:
  type{ 'title':
         argument => value,
         otherarg => value
      }

node default {
$mypackages = [ 'apache2', 'sudo', 'screen' ]

package { $mypackages: ensure => 'installed' }
}

node default {

# creating the directory called test
file{ '/tmp/test':
     ensure => 'directory'
}

}


node default {

# creating the directory called test
file{ '/tmp/test1':
     ensure => 'directory',
     owner => 'root',
     group => 'root',
     mode => '0777',
}

}

node default {

# remove the given file
tidy { '/tmp/3.txt': }
}

eg:
Ex1  Verify nginx is installed
 
   package{ 'nginx':
         ensure => present,
       }
Ex2  Create a file /tmp/file1.txt

   file{'file1':
        path=>'/tmp/file1.txt'
       }
Ex3 Start a service

   service{ 'httpd':
           ensure=>running,
           enable=>true
          } 
----

Classes
  classes are the groups of different resources.
 
class directories {

  # create a directory
  file { '/etc/site-conf':
    ensure => 'directory',
  }

  # a fuller example, including permissions and ownership
  file { '/var/log/admin-app-log':
    ensure => 'directory',
    owner  => 'root',
    group  => 'wheel',
    mode   => '0750',
  }

  # this example  creates a file
  file { '/etc/site-conf/':
    ensure => 'present',
  }
}
Resource type Reference
  puppet describe file
  puppet describe --list

          
  
------------------PUPPET INSTALLATION ON UBUNTU------------

Installing Puppet Master
Step 1: Run the following commands for installing Puppet Master
$ sudo apt-get update
$ sudo apt-get install wget
$ wget https://apt.puppetlabs.com/puppet-release-bionic.deb
$ sudo dpkg -i puppet-release-bionic.deb
$ sudo apt-get update

$ sudo apt-get install puppet-master
$ sudo systemctl status puppet-master.service

Add the following lines in the puppet-master configuration file
Next open port 8140 on the Puppet Master’s firewall
$ sudo nano /etc/default/puppet-master
JAVA_ARGS="-Xms512m Xmx512m" 
$ sudo systemctl restart puppet-master
$ sudo ufw allow 8140/tcp

Installing Puppet Agent

Step 2: Run the following commands for installing Puppet Agent

$ sudo apt-get update
$ sudo apt-get install wget
$ wget https://apt.puppetlabs.com/puppet-release-bionic.deb
$ sudo dpkg -i puppet-release-bionic.deb
$ sudo apt-get install puppet
$ sudo nano /etc/hosts
   add ip address of the master
$ sudo systemctl start puppet
$ sudo systemctl enable puppet


Step 3: Make changes to the hosts file which exists in /etc/hosts. And add the Puppet
Master IP address along with the name “puppet”

$ sudo nano /etc/hosts

Step 4: Create the following directory path:

$ sudo mkdir -p /etc/puppet/code/environments/production/manifests


Configuring Puppet Slave

Step 1: Add the entry for Puppet Master in /etc/hosts

Step 2: Finally start the Puppet agent by using the following command. Also, enable the
service, so that it starts when the computer starts

$ sudo systemctl start puppet
$ sudo systemctl enable puppet


On Master

$ sudo puppet cert list

Step 2: Finally, sign the listed certificate using the following command:
$ sudo puppet cert sign --all

On master machine create /etc/puppet/code/environments/production/manifests/site.pp

node default{

package {'nginx':
ensure => installed,
}

file { '/tmp/status.txt':

content => 'installed',
mode => '0644',
}
}

Goto client machine and run the command
puppet agent --test

-----------Find the resource types
puppet resource --types
puppet resource file /tmp/1.txt

----To set the running interval on client machine
By default the running interval on the client is 30 mins. but we can change it by changing /etc/puppet/puppet.conf
[agent]
server=puppet
runinterval=1m

Classes

in site.pp
#---Create testuser
class addusers
{
  user { 'testuser':
        ensure=>present
       }
}
node default {
class { addusers:}
}
--------------
Facts
node default

{
$message=$facts['os']['family'] ? {
'RedHat'=> 'running redhat',
default=> 'running somewhere',
}
notify { $message: }
}

------
mkdir -p /etc/facter/facts.d
 cd /etc/facter/facts.d/
 create file customfact.txt and add content
customfact="hello world"

Now run following command
---------
Templates
#Create file test.epp

<% | String $text, Boolean $bool | -%>
Text value <%= $text %>

<% if $bool { -%>
Bool has true value
<% } -%>

To validate the syntax
puppet epp validate test.epp
To run the template
puppet epp render test.epp --values '{ text => "Hello world", bool => true }'

facter customfact

Modules:-
it is the collection of manifest with data( such as facts files and templates) and they have a specific directory structure. Modules are useful to organize puppet code because they allow you to split the code in multiple manifests.It is considered to be best practice to use modules to organize manifests.