While it’s entirely possible to use Puppet by mapping component classes directly to nodes, most systems’ infrastructure have similar configurations. Therefore, Puppet can use profiles and roles to help us create a layer of indirection between our component modules and nodes that lets us administer more generalized roles directly to our nodes. For example, instead of having to include the `apache`, `mysql`, and `php` modules directly to a server, we can create a series of related profiles. Furthermore, we can pull them all together into a single role, and then apply that role to the relevant hosts.
Specifically, profiles are wrapped classes that contain our component modules and relevant configuration settings for a layer of our technology stack, while roles help us with building and configuring a complete system. In this lab, we’ll use this concept to write three profiles related to MySQL, and then apply them to an overall MySQL host role.
Learning Objectives
Successfully complete this lab by achieving the following learning objectives:
- Create the Base Profile
Move into the
modulesdirectory in theproductionenvironment:cd /etc/puppetlabs/code/environments/production/modules
Add the necessary modules:
sudo puppet module install puppetlabs-ntp –version 8.0.0
sudo puppet module install puppetlabs-motd –version 3.0.0Create the
profilemodule to store our profiles:sudo pdk new module profile
Set the Puppet Forge username and module author to your own information; leave the licensing with the default setting, and deselect Windows for the supported operating systems.
Create the
baseprofile:cd profile
sudo pdk new class baseOpen the
baseclass file, and update it to include thentpmodule and set anymotdmessage you want.sudo vim manifests/base.pp
@summary
Base module for all nodes
#
@example
include profile::base
class profile::base {
include ntpclass { 'motd': content => "Hi there!n", }}
Save and exit.
- Create the MySQL Server Profile
Pull down the
mysqlmodule from the Forge:cd ..
sudo puppet module install puppetlabs-mysql –version 9.0.0Create the
mysql::serverclass:cd profile
sudo pdk new class mysql::serverNotice how this automatically creates a
mysqldirectory undermanifests.Open the new class and update it so that we use the new
mysqlmodule with the appropriate configuration settings:sudo vim manifests/mysql/server.pp
class profile::mysql::server {
class { ‘::mysql::server’:
root_password => ‘strongpassword’,
remove_default_accounts => true,
override_options => {
mysqld => {
log-error => ‘/var/log/mysql-error.log’,
},
}
}
}
- Create the MySQL Client Class
Create the class:
sudo pdk new class mysql::client
Update the class to include the client component class:
sudo vim manifests/mysql/client.pp
@summary
Set up the client configuration for mysql
#
@example
include profile::mysql::client
class profile::mysql::client {
class {‘::mysql::client’:
package_name => ‘mysql-client’,
package_ensure => ‘1:5.5.60-1.el7_5’,
bindings_enable => true,
}
}
- Create the MySQL Server Role
Create the
rolemodule:cd ..
sudo pdk new module role
cd role/Create the
mysql::serverclass for our mysql server role:sudo pdk new class mysql::server
Add all of our profiles to the role:
sudo vim manifests/mysql/server.pp
@summary
Configures a complete mysql host
#
@example
include role::mysql::server
class role::mysql::server {
include profile::base
include profile::mysql::server
include profile::mysql::client
}
- Test the Role
On the additional node, set up Puppet:
curl -k https://puppet.ec2.internal:8140/packages/current/install.bash | sudo bash
On the master, sign the cert:
sudo puppetserver ca sign –all
Add the role to the node in the main manifest:
sudo vim ../../manifests/site.pp
node node1.ec2.internal {
include role::mysql::server
}Return to the additional node, switch to
root, and perform a Puppet run:sudo -i
puppet agent -t
