Puppet Guide

Red Hat Satellite 6.2

A guide to building your own Puppet module and importing it into Satellite 6

Red Hat Satellite Documentation Team

Abstract

Puppet is a system configuration tool used in Red Hat Satellite 6. This book runs through the creation of a basic Puppet Module and how to use this module in your Red Hat Satellite 6 infrastructure.

Chapter 1. Overview

Puppet is a tool for applying and managing system configurations. Puppet collects system information, or facts, and uses this information to create a customized system configuration using a set of modules. These modules contain parameters, conditional arguments, actions, and templates. Puppet is used as either a local system command-line tool or in a client-server relationship where the server acts as the Puppet master and applies configuration to multiple client systems using a Puppet agent. This provides a way to automatically configure newly provisioned systems, either individually or simultaneously to create a specific infrastructure.

1.1. Defining the Puppet Workflow

Puppet uses the following workflow to apply configuration to a system.

  1. Collect facts about each system. These facts can include hardware, operating systems, package versions, and other information. The Puppet agent on each system collects this information and sends it to the Puppet master.
  2. The Puppet master generates a custom configuration for each system and sends it to the Puppet agent. This custom configuration is called a catalog.
  3. The Puppet agent applies the configuration to the system.
  4. The Puppet agent sends a report back to the Puppet master that indicates the changes applied and if any changes were unsuccessful.
  5. Third-party applications can collect these reports using Puppet’s API.

1.2. Using Puppet on Satellite 6

Satellite 6 uses Puppet in several ways:

  • Satellite 6 imports Puppet modules used to define the system configuration. This includes control over module versions and their environments.
  • Satellite 6 imports sets of parameters, also known as Puppet Smart Class parameters, from Puppet modules. Users can accept the default values from Puppet classes or provide their own at a global or system-specific level.
  • Satellite 6 triggers the execution of Puppet between the master and the respective agents on each system. Puppet runs can occur either:

    • Automatically, such as after the provisioning process completes or as a daemon that checks and manages the machine’s configuration over its life cycle.
    • Manually, such as when the administrator needs to trigger an immediate Puppet run.
  • Satellite 6 collects reports from Puppet after the configuration workflow completes. This helps with auditing and archiving system configuration over long term periods.

These functions provide an easy way for users to control system configuration aspects of the application life cycle using Puppet.

If required, to find out the version of Puppet used in your Satellite environment, see the Red Hat Knowledgebase article Satellite 6 Component Versions.

1.3. Puppet Performance and Scalability on Satellite 6

The performance of Puppet in Satellite 6 is driven more by the Satellite and Capsule storage capacity, CPU performance, and available memory, than by application limitations. Therefore, testing of your hardware and configuration is the only way to be sure the performance is acceptable for your needs.

For Satellite 6.2, the maximum number of concurrent Puppet runs is approximately 320. This should improve significantly in Satellite 6.3 due to Puppet Server replacing the Apache Passenger module and Puppet master.

Importing many Puppet modules simultaneously can take a long time. For example, on a notebook with 8GB RAM and 4 cores, importing 2000 modules takes approximately 4 minutes.

The following performance brief in the Red Hat Knowledgebase provides examples of performance tests made for Satellite 6.2: Performance & Scale Tuning of Satellite 6.2 and Capsules. The performance of Satellite 6.3 is expected to be noticeably better than indicated in the performance brief for Satellite 6.2.

For information on recommended storage and hardware requirements, see Hardware Requirements in the Red Hat Satellite Installation Guide.

Chapter 2. Building Puppet Modules from Scratch

This chapter explores how to build and test your own Puppet modules. This includes a basic tutorial on creating a Puppet module that deploys a simple web server configuration.

2.1. Examining the Anatomy of a Puppet Module

Before creating our module, we need to understand the components that create a Puppet module.

Manifests

Manifests are files that contain code to define a set of resources and their attributes. A resource is any configurable part of a system. Examples of resources include packages, services, files, users and groups, SELinux configuration, SSH key authentication, cron jobs, and more. A manifest defines each required resource using a set of key-value pairs for their attributes. For example:

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

This declaration checks if the httpd package is installed. If not, the manifest executes yum and installs it.

Manifests are located in the manifest directory of a module.

Puppet modules also use a test directory for test manifests. These manifests are used to test certain classes contained in your official manifests.

Static Files

Modules can contain static files that Puppet can copy to certain locations on your system. These locations, and other attributes such as permissions, are defined through file resource declarations in manifests.

Static files are located in the files directory of a module.

Templates

Sometimes configuration files require custom content. In this situation, users would create a template instead of a static file. Like static files, templates are defined in manifests and copied to locations on a system. The difference is that templates allow Ruby expressions to define customized content and variable input. For example, if you wanted to configure httpd with a customizable port then the template for the configuration file would include:

Listen <%= @httpd_port %>

The httpd_port variable in this case is defined in the manifest that references this template.

Templates are located in the templates directory of a module.

Plug-ins

Plug-ins allow for aspects that extend beyond the core functionality of Puppet. You can use plug-ins to define custom facts, custom resources, or new functions. For example, a database administrator might need a resource type for PostgreSQL databases. This could help the database administrator populate PostgreSQL with a set of new databases after installing PostgreSQL. As a result, the database administrator need only create a Puppet manifest that ensures PostgreSQL installs and the databases are created afterwards.

Plug-ins are located in the lib directory of a module. This includes a set of subdirectories depending on the plug-in type. For example:

  • /lib/facter — Location for custom facts.
  • /lib/puppet/type — Location for custom resource type definitions, which outline the key-value pairs for attributes.
  • /lib/puppet/provider — Location for custom resource providers, which are used in conjunction with resource type definitions to control resources.
  • /lib/puppet/parser/functions — Location for custom functions.

2.2. Setting up a Puppet Development System

A Puppet development system is useful for creating and testing your own modules. It is recommended to use a new system with a Red Hat Enterprise Linux 6 or 7 subscription.

After installing the new system and registering your version of Red Hat Enterprise Linux, enable the Red Hat Satellite 6 Tools repository. For example, for Red Hat Enterprise Linux 7:

# subscription-manager repos --enable=rhel-7-server-satellite-tools-6.2-rpms

After enabling the repository, install the puppet package and the standard library of resources for Puppet modules puppetlabs-stdlib:

# yum install puppet puppetlabs-stdlib

2.3. Generating a New Module Boilerplate

The first step in creating a new module is to change to the Puppet module directory and create a basic module structure. Either create this structure manually or use Puppet to create a boilerplate for your module:

# cd /etc/puppet/modules
# puppet module generate user_name-module_name

An interactive wizard appears and guides you through populating the module’s metadata.json file with metadata.

Important

The puppet module generate command requires the module name take the format of user_name-module_name to comply with Puppet Forge specifications. However, to test our tutorial module and use it with Satellite 6 we need to rename the module directory to remove the user name. For example, for user_name-mymodule you would run:

# puppet module generate user_name-mymodule
# mv user_name-mymodule mymodule

When the module generation process completes, the new modules contains some basic files, including a manifests directory. This directory already contains a manifest file called init.pp, which is the module’s main manifest file. View the file to see the empty class declaration for the module:

class mymodule {


}

The module also contains a tests directory containing a manifest also named init.pp. This test manifest contains a reference to the mymodule class within manifests/init.pp:

include mymodule

Puppet will use this test manifest to test our module.

We are now ready to add our system configuration to our module.

2.4. Installing a HTTP Server

Our Puppet module will install the packages necessary to run an HTTP server. This requires a resource definition that defines configurations for the httpd package.

In the module’s manifests directory, create a new manifest file called httpd.pp:

# touch mymodule/manifests/httpd.pp

This manifest will contain all HTTP configuration for our module. For organizational purposes, we will keep this manifest separate from the init.pp manifest.

Add the following content to the new httpd.pp manifest:

class mymodule::httpd {
  package { 'httpd':
    ensure => installed,
  }
}

This code defines a subclass of mymodule called httpd, then defines a package resource declaration for the httpd package. The ensure ⇒ installed attribute tells Puppet to check if the package is installed. If it is not installed, Puppet executes yum to install it.

We also need to include this subclass in our main manifest file. Edit the init.pp manifest:

class mymodule {
  include mymodule::httpd
}

It is now time to test the module. Run the following command:

# puppet apply mymodule/tests/init.pp --noop

The puppet apply command applies the configuration in the manifest to your system. We use the test init.pp manifest, which refers to the main init.pp manifest. The --noop performs a dry run of the configuration, which shows only the output but does not actually apply the configuration. The output should resemble the following:

Notice: Compiled catalog for puppet.example.com in environment production in 0.59 seconds
Notice: /Stage[main]/Mymodule::Httpd/Package[httpd]/ensure: current_value absent, should be present (noop)
Notice: Class[Mymodule::Httpd]: Would have triggered 'refresh' from 1 events
Notice: Stage[main]: Would have triggered 'refresh' from 1 events
Notice: Finished catalog run in 0.67 seconds

The highlighted line is the result of the ensure ⇒ installed attribute. The current_value absent means that Puppet has detected the httpd package is not installed. Without the --noop option, Puppet would install the httpd package.

2.5. Running the HTTP Server

After installing the httpd package, we start the service using another resource declaration: service.

Edit the httpd.pp manifest and add the highlighted lines:

class mymodule::httpd {
  package { 'httpd':
    ensure => installed,
  }
  service { 'httpd':
    ensure => running,
    enable => true,
    require => Package["httpd"],
  }
}

This achieves a couple of things:

  • The ensure ⇒ running attribute checks if the service is running. If not, Puppet starts it.
  • The enable ⇒ true attribute sets the service to run when the system boots.
  • The require ⇒ Package["httpd"] attribute defines an ordering relationship between one resource declaration and another. In this case, it ensures the httpd service starts after the httpd package installs. This creates a dependency between the service and its respective package.

Run the puppet apply command again to test the changes to our module:

# puppet apply mymodule/tests/init.pp --noop
Notice: Compiled catalog for puppet.example.com in environment production in 0.56 seconds
Notice: /Stage[main]/Mymodule::Httpd/Package[httpd]/ensure: current_value absent, should be present (noop)
Notice: /Stage[main]/Mymodule::Httpd/Service[httpd]/ensure: current_value stopped, should be running (noop)
Notice: Class[Mymodule::Httpd]: Would have triggered 'refresh' from 2 events
Notice: Stage[main]: Would have triggered 'refresh' from 1 events
Notice: Finished catalog run in 0.41 seconds

The highlighted line is the result of our new resource definition for the httpd service.

2.6. Configuring the HTTP Server

The HTTP Server is now installed and enabled. The next step is to provide some configuration. The HTTP server already provides some default configuration in /etc/httpd/conf/httpd.conf, which provides a web server on port 80. We will add some additional configuration to provide an additional web server on a user-specified port.

We use a template file to store our configuration content because the user-defined port requires variable input. In our module, create a directory called templates and add a file called myserver.conf.erb in the new directory. Add the following contents to the file:

Listen <%= @httpd_port %>
NameVirtualHost *:<%= @httpd_port %>
<VirtualHost *:<%= @httpd_port %>>
  DocumentRoot /var/www/myserver/
  ServerName <%= @fqdn %>
  <Directory "/var/www/myserver/">
    Options All Indexes FollowSymLinks
    Order allow,deny
    Allow from all
  </Directory>
</VirtualHost>

This template follows the standard syntax for Apache web server configuration. The only difference is the inclusion of Ruby escape characters to inject variables from our module. For example, httpd_port, which we use to specify the web server port.

Notice also the inclusion of fqdn, which is a variable that stores the fully qualified domain name of the system. This is known as a system fact. System facts are collected from each system prior to generating each respective system’s Puppet catalog. Puppet uses the facter command to gather these system facts and you can also run facter to view a list of these facts.

Edit the httpd.pp manifest and add the highlighted lines:

class mymodule::httpd {
  package { 'httpd':
    ensure => installed,
  }
  service { 'httpd':
    ensure => running,
    enable => true,
    require => Package["httpd"],
  }
  file {'/etc/httpd/conf.d/myserver.conf':
  notify => Service["httpd"],
    ensure => file,
    require => Package["httpd"],
    content => template("mymodule/myserver.conf.erb"),
  }
  file { "/var/www/myserver":
    ensure => "directory",
  }
}

This achieves the following:

  • We add a file resource declaration for the server configuration file /etc/httpd/conf.d/myserver.conf.
  • We add a relationship between the configuration file and the httpd service using the notify ⇒ Service["httpd"] attribute. This checks our configuration file for any changes. If the file has changed, Puppet restarts the service.
  • We check the httpd package is installed before adding this file.
  • The content for this /etc/httpd/conf.d/myserver.conf file is the myserver.conf.erb template we created earlier.
  • We add a second file resource declaration. This one creates a directory /var/www/myserver/ for our web server.

We also need to include the httpd_port parameter in our main manifest file. Edit the init.pp manifest and add the following text shown in bold:

class mymodule (
  $httpd_port = 8120
) {
  include mymodule::httpd
}

This sets the httpd_port parameter to a default value of 8120. You can override this value with the Satellite Server.

Run the puppet apply command again to test the changes to our module:

# puppet apply mymodule/tests/init.pp --noop
Warning: Config file /etc/puppet/hiera.yaml not found, using Hiera defaults
Notice: Compiled catalog for puppet.example.com in environment production in 0.84 seconds
Notice: /Stage[main]/Mymodule::Httpd/File[/var/www/myserver]/ensure: current_value absent, should be directory (noop)
Notice: /Stage[main]/Mymodule::Httpd/Package[httpd]/ensure: current_value absent, should be present (noop)
Notice: /Stage[main]/Mymodule::Httpd/File[/etc/httpd/conf.d/myserver.conf]/ensure: current_value absent, should be file (noop)
Notice: /Stage[main]/Mymodule::Httpd/Service[httpd]/ensure: current_value stopped, should be running (noop)
Notice: Class[Mymodule::Httpd]: Would have triggered 'refresh' from 4 events
Notice: Stage[main]: Would have triggered 'refresh' from 1 events
Notice: Finished catalog run in 0.51 seconds
Note

The warning for the hiera.yaml file is safe to ignore.

The highlighted lines show the creation of the configuration file and our web server directory.

2.7. Configuring the Firewall

The web server requires an open port so people can access the pages hosted on our web server. The open problem is that different versions of Red Hat Enterprise Linux uses different methods for controlling the firewall. For Red Hat Enterprise Linux 6 and below, we use iptables. For Red Hat Enterprise Linux 7, we use firewalld.

This decision is something Puppet handles using conditional logic and system facts. For this step, we add a statement to check the operating system and run the appropriate firewall commands.

Add the following code inside your mymodule::http class:

  if versioncmp($::operatingsystemmajrelease, '6') <= 0 {
    exec { 'iptables':
      command => "iptables -I INPUT 1 -p tcp -m multiport --ports ${httpd_port} -m comment --comment 'Custom HTTP Web Host' -j ACCEPT &amp;&amp; iptables-save > /etc/sysconfig/iptables",
      path => "/sbin",
      refreshonly => true,
      subscribe => Package['httpd'],
    }
    service { 'iptables':
      ensure => running,
      enable => true,
      hasrestart => true,
      subscribe => Exec['iptables'],
    }
  }
  elsif $operatingsystemmajrelease == 7 {
    exec { 'firewall-cmd':
      command => "firewall-cmd --zone=public --add-port=${httpd_port}/tcp --permanent",
      path => "/usr/bin/",
      refreshonly => true,
      subscribe => Package['httpd'],
    }
    service { 'firewalld':
      ensure => running,
      enable => true,
      hasrestart => true,
      subscribe => Exec['firewall-cmd'],
    }
  }

This code performs the following:

  • Use the operatingsystemmajrelease fact to determine whether the operating system is Red Hat Enterprise Linux 6 or 7.
  • If using Red Hat Enterprise Linux 6, declare an executable (exec) resource that runs iptables and iptables-save to add a permanent firewall rule. The httpd_port variable is used inline to define the port to open. After the exec resource completes, we trigger a refresh of the iptables service. To achieve this, we define a service resource that includes the subscribe attribute. This attribute checks if there are any changes to another resource and, if so, performs a refresh. In this case, it checks the iptables executable resource.
  • If using Red Hat Enterprise Linux 7, declare a similar executable resource that runs firewall-cmd to add a permanent firewall rule. The httpd_port variable is also used inline to define the port to open. After the exec resource completes, we trigger a refresh of the firewalld service but with a subscribe attribute pointing to the firewall-cmd executable resource.
  • The code for both firewall executable resources contains refreshonly ⇒ true and subscribe ⇒ Package['httpd'] attributes. This ensures the firewall commands only run after the httpd installs. Without these attributes, subsequent runs will add multiple instances of the same firewall rule.

Run the puppet apply command again to test the changes to our module. The following example is a test of Red Hat Enterprise Linux 6:

# puppet apply mymodule/tests/init.pp --noop
Warning: Config file /etc/puppet/hiera.yaml not found, using Hiera defaults
Notice: Compiled catalog for puppet.example.com in environment production in 0.82 seconds
Notice: /Stage[main]/Mymodule::Httpd/Exec[iptables]/returns: current_value notrun, should be 0 (noop)
Notice: /Stage[main]/Mymodule::Httpd/Service[iptables]: Would have triggered 'refresh' from 1 events
...

The highlighted lines show the execution of the firewall rule creation and the subsequent service refresh as a result of the subscribe attribute.

Important

This configuration serves only as an example of using conditional statements. If you aim to manage multiple firewall rules for your system in the future, it is recommended to create a custom resource for firewalls. It is inadvisable to use executable resources to constantly chain many Bash commands.

2.8. Configuring SELinux

SELinux restricts non-standard access to the HTTP server by default. If we define a custom port, we need to add configuration that allows SELinux to grant access.

Puppet contains resource types to manage some SELinux functions, such as Booleans and modules. However, we need to execute the semanage command to manage port settings. This tool is a part of the policycoreutils-python package, which is not installed on Red Hat Enterprise Linux systems by default.

Add the following code inside your mymodule::http class:

  exec { 'semanage-port':
    command => "semanage port -a -t http_port_t -p tcp ${httpd_port}",
    path => "/usr/sbin",
    require => Package['policycoreutils-python'],
    before => Service['httpd'],
    subscribe => Package['httpd'],
    refreshonly => true,
  }
  package { 'policycoreutils-python':
    ensure => installed,
  }

This code performs the following:

  • The require ⇒ Package['policycoreutils-python'] attribute makes sure the policycoreutils-python is installed prior to executing the command.
  • Puppet executes semanage, using httpd_port as a variable, to add the custom port to the list of TCP ports Apache is allowed to listen on.
  • The before ⇒ Service ['httpd'] makes sure to execute this command before the httpd service starts. If httpd starts before the SELinux command, SELinux denies access to the port and the service fails to start.
  • The code for the SELinux executable resource contains refreshonly ⇒ true and subscribe ⇒ Package['httpd'] attributes. This ensures the SELinux commands only run after the httpd installs. Without these attributes, subsequent runs result in failure. This is because SELinux detects the port is already enabled and reports an error.

Run the puppet apply command again to test the changes to our module.

# puppet apply mymodule/tests/init.pp --noop
...
Notice: /Stage[main]/Mymodule::Httpd/Package[policycoreutils-python]/ensure: current_value absent, should be present (noop)
...
Notice: /Stage[main]/Mymodule::Httpd/Exec[semanage-port]/returns: current_value notrun, should be 0 (noop)
...
Notice: /Stage[main]/Mymodule::Httpd/Service[httpd]/ensure: current_value stopped, should be running (noop)
...

Puppet installs policycoreutils-python first, then configures port access before starting the httpd service.

2.9. Copying a HTML file to the Web Host

The HTTP server configuration is now complete. This provides a platform for installing a web-based application, which Puppet can also configure. For this example, however, we will only copy over a simple index web page to our web server.

Create a file named index.html in the files directory. Add the following content to this file:

<html>
  <head>
    <title>Congratulations</title>
  <head>
  <body>
    <h1>Congratulations</h1>
    <p>Your puppet module has correctly applied your configuration.</p>
  </body>
</html>

Create a manifest named app.pp in the manifests directory. Add the following content to this file:

class mymodule::app {
  file { "/var/www/myserver/index.html":
    ensure => file,
    mode   => '755',
    owner  => root,
    group  => root,
    source => "puppet:///modules/mymodule/index.html",
    require => Class["mymodule::httpd"],
  }
}

This new class contains a single resource declaration. This declaration copies a file from the module’s file directory from the Puppet Server to the system and sets its permissions. Additionally, the require attribute ensures the mymodule::http class completes the configuration successfully before we apply mymodule::app.

Finally, include this new manifest in our main init.pp manifest:

class mymodule (
  $httpd_port = 8120
) {
  include mymodule::httpd
  include mymodule::app
}

Run the puppet apply command again to test the changes to our module. The output should resemble the following:

# puppet apply mymodule/tests/init.pp --noop
Warning: Config file /etc/puppet/hiera.yaml not found, using Hiera defaults
Notice: Compiled catalog for puppet.example.com in environment production in 0.66 seconds
Notice: /Stage[main]/Mymodule::Httpd/Exec[iptables]/returns: current_value notrun, should be 0 (noop)
Notice: /Stage[main]/Mymodule::Httpd/Package[policycoreutils-python]/ensure: current_value absent, should be present (noop)
Notice: /Stage[main]/Mymodule::Httpd/Service[iptables]: Would have triggered 'refresh' from 1 events
Notice: /Stage[main]/Mymodule::Httpd/File[/var/www/myserver]/ensure: current_value absent, should be directory (noop)
Notice: /Stage[main]/Mymodule::Httpd/Package[httpd]/ensure: current_value absent, should be present (noop)
Notice: /Stage[main]/Mymodule::Httpd/File[/etc/httpd/conf.d/myserver.conf]/ensure: current_value absent, should be file (noop)
Notice: /Stage[main]/Mymodule::Httpd/Exec[semanage-port]/returns: current_value notrun, should be 0 (noop)
Notice: /Stage[main]/Mymodule::Httpd/Service[httpd]/ensure: current_value stopped, should be running (noop)
Notice: Class[Mymodule::Httpd]: Would have triggered 'refresh' from 8 events
Notice: /Stage[main]/Mymodule::App/File[/var/www/myserver/index.html]/ensure: current_value absent, should be file (noop)
Notice: Class[Mymodule::App]: Would have triggered 'refresh' from 1 events
Notice: Stage[main]: Would have triggered 'refresh' from 2 events
Notice: Finished catalog run in 0.74 seconds

The highlighted line shows that the index.html file would be copied to the web server.

2.10. Finalizing the Module

Our module is ready for use. To export the module into an archive for Red Hat Satellite 6 to use, enter the following command:

# puppet module build mymodule

This creates an archive file at mymodule/pkg/mymodule-0.1.0.tar.gz, which contains the contents of our mymodule directory. We upload this module to our Red Hat Satellite 6 Server to provision our own HTTP server.

If any changes are required, edit the files within the modules directories and rebuild the module using the puppet module build command. The changes will only be reflected in Satellite if the module version is increased. To increase the version number, edit the /etc/puppet/modules/mymodule/metadata.json file and then rebuild the module. Upload and publish the new version in Satellite Server.

Chapter 3. Adding Puppet Modules to Red Hat Satellite 6

Puppet modules form a part of a Satellite Product in Red Hat Satellite 6. This means you must create a custom Product and then upload the modules that form the basis of that Product. For example, a custom Product might consist of a set of Puppet modules required to setup an HTTP server, a database, and a custom application. Custom Products can also include repositories with RPM packages that apply to your application.

3.1. Creating a Custom Product

The first step to adding our Puppet module is to create a custom Product.

Creating a Custom Product

  1. Login to your Red Hat Satellite 6 Server.
  2. Navigate to Content > Products.
  3. Click + New Product.
  4. Provide your custom Product with a Name. In this example, use MyProduct as the name.
  5. The Label field automatically populates with a label based on the Name.
  6. Provide a GPG Key, Sync Plan, and a Description if required. For our example, leave those fields blank.
  7. Click Save.

Satellite now has a new Product called MyProduct.

3.2. Creating a Puppet Repository in a Custom Product

The next procedure creates a Puppet repository in our custom Product.

Creating a Custom Puppet Repository

  1. On the Products page, click on the custom Product created previously (MyProduct).
  2. Navigate to the Repositories subtab.
  3. Click Create Repository.
  4. Provide the repository with a Name. This example uses the name MyRepo.
  5. The Label field automatically populates with a label based on the Name.
  6. Select puppet as the repository Type.
  7. Leave the URL field blank. This field is used for remote repositories, but in our case Satellite 6 creates its own repository.
  8. Click Save.

The custom Product now contains a repository to store our Puppet modules.

3.3. Uploading a Puppet Module to a Repository

Now we upload our mymodule module to the newly created repository, which adds it to our custom Product.

  1. Click the Name of the newly created repository.
  2. In the Upload Puppet Module section, click Browse and select the mymodule archive.
  3. Click Upload.

You can upload more modules to this repository. For our example, we only need to upload the mymodule module.

Our Puppet module is now a part of your Red Hat Satellite 6 environment. Next we publish the module as part of a content view.

3.4. Removing a Puppet Module from a Repository

If you aim to remove redundant modules from custom repositories in the future, use the Manage Puppet Modules feature.

  1. On the Products page, click on the custom Product containing the module to remove.
  2. Click the Name of the repository containing the module to remove.
  3. Click Manage Puppet Modules. The screen displays a list of Puppet modules contained within the repository.
  4. Select the modules to remove.
  5. Click Remove Puppet Modules.

Satellite removes the chosen modules from your repository.

3.5. Adding Puppet Modules from a Git Repository

As an alternative to manually uploading modules, Red Hat Satellite 6 includes a utility called pulp-puppet-module-builder. This tool checks out repositories containing a set of modules, builds the modules, and publishes them in a structure for Satellite 6 to synchronize. This provides an efficient way to manage module development in Git and include them in the Satellite 6 workflow.

The use of Modulefile is deprecated since Puppet version 3. If you build any Puppet module containing a Modulefile when using Puppet version 3.X, a deprecation warning is printed. Satellite 6.3 will include Puppet version 4 which will ignore the Modulefile data. The data in the Modulefile must be moved to a metadata.json file. You can convert a module to use a metadata.json file as follows:

  1. Run puppet module build Module_Directory once.
  2. Delete the Modulefile.
  3. Check the updated metadata.json file into the revision control repository.
Note

You can also install the pulp-puppet-module-builder tool on other machines using the pulp-puppet-tools package.

One common method is to run the utility on the Satellite 6 Server itself and publish to a local directory.

Publishing a Git Repository to a Local Directory

  1. Create a directory on the Satellite Server to synchronize the modules:

    # mkdir /var/www/puppet-modules
    # chmod 755 /var/www/puppet-modules

    Store your modules under the /var/www/ directory, otherwise SELinux will block the repository synchronization. If required to use another directory, you can use the httpd_sys_r_content_t or pulp_tmp_t SELinux type. Using the httpd_sys_r_content_t SELinux type allows the webserver to read the files. See the SELinux User’s and Administrator’s Guide for information on setting SELinux file types.

  2. Run the pulp-puppet-module-builder and checkout the Git repository:

    # pulp-puppet-module-builder --output-dir=/var/www/puppet-modules \
    --url=git@mygitserver.com:mymodules.git --branch=develop

    This checks out the develop branch of the Git repository from git@mygitserver.com:mymodules.git and publishes the modules to /var/www/puppet-modules/.

The same procedure applies to publishing modules to an HTTP server.

Publishing Git Repository to a Web Server

  1. Create a directory on the web server to synchronize the modules.

    # mkdir /var/www/html/puppet-modules
    # chmod 755 /var/www/html/puppet-modules
  2. Run the pulp-puppet-module-builder and checkout the Git repository.

    # pulp-puppet-module-builder \
    --output-dir=/var/www/html/puppet-modules \
    --url=git@mygitserver.com:mymodules.git --branch=develop

    This checks out the develop branch of the Git repository from git@mygitserver.com:mymodules.git and publishes the modules to /var/www/html/puppet-modules/.

In the Satellite 6 web UI, create a new repository with the URL set to the location of your published modules.

Creating a Repository for Puppet Modules from Git

  1. On the Products page, click on the custom Product created previously (MyProduct).
  2. Navigate to the Repositories subtab.
  3. Click Create Repository.
  4. Provide the repository with a Name. This example uses the name MyGitRepo.
  5. The Label field automatically populates with a label based on the Name.
  6. Select puppet as the repository Type.
  7. In the URL field, set the location you defined earlier. For example, local directories on the Satellite 6 Server use the file:// protocol:

    file:///modules

    A remote repository uses the http:// protocol:

    http://webserver.example.com/modules/
  8. Click Save.
  9. Click Sync Now to synchronize the repository.

The Puppet modules in the Git repository are now included in your Satellite 6 Server.

3.6. Publishing a Content View

The final step to getting our Puppet module ready for consumption is to publish it as part of a content view. You can add this module to an existing view but for our example we will create a new view.

Publishing a Content View

  1. Navigate to Content > Content Views.
  2. Click + Create New View.
  3. Provide your view with a Name. In this example, we use MyView as the name.
  4. The Label field automatically populates with a label based on the Name.
  5. Make sure Composite Content View is not selected.
  6. Click Save.
  7. Select the Name of your newly created view.
  8. Navigate to Content > Repositories.
  9. Add the required Red Hat Enterprise Linux repositories, including a base Red Hat Enterprise Linux Server RPM collection and a Red Hat Satellite Tools RPM collection for the same version. The Tools RPM collection contains the packages to set up our remote Puppet configuration on provisioned systems.
  10. Navigate to Puppet Modules.
  11. Click + Add New Module.
  12. Scroll to your module and click Select a Version.
  13. Scroll to the module version Use Latest and click Select Version.
  14. Our module is now a part of the content view. Navigate to Versions to publish and promote a new version of the content view.
  15. Click Publish New Version. On the Publish New Version page, click Save. This publishes the content view with our module.
  16. Scroll to the new version of our view and click Promote. Choose a life-cycle environment and click Promote Version. This makes the view a part of the chosen life-cycle environment.

Our content view is now published. As a part of the content view creation, Red Hat Satellite 6 creates a new Puppet environment for use in the provisioning process. This Puppet environment contains our module. You can view this new Puppet environment on the Configure > Environments page.

3.7. Puppet Environments

A Puppet environment is defined as an isolated set of Puppet agent nodes that can be associated with a specific set of Puppet modules. In Satellite 6 context we can think of a Puppet environment as a set of Hosts running the Puppet agent that are associated with a specific set of Puppet modules. For example, nodes that are associated with environment Production only have access to the modules that are in environment Production.

Puppet environments are used to separate Puppet modules from different types of Host. A typical use is to enable changes to a module to be tested in one environment before being pushed to another. A Puppet module can contain facts and functions as well as one or more Puppet Classes that you can assign to Hosts. Modules are part of an environment, Puppet Classes are only part of an environment because they are part of a module.

In Red Hat Satellite, a Puppet environment will be created automatically for a Content View if the CV has a Puppet module. The automatically created Puppet environment name includes the organization label, the life-cycle environment, the Content View name, and the content view ID. For example, KT_Example_Org_Library_RHEL6Server_3.

Creating Puppet Environments within Red Hat Satellite

Navigate to Configure > Environments and click New Puppet Environment. Give the new environment a name and click Submit to save the changes. Note that if the environment does not exist on the Puppet master and you subsequently run an import, Satellite will prompt for the environment to be deleted.

Importing Puppet Environments to Red Hat Satellite

Satellite can detect all the environments and Puppet modules contained on a Puppet master, and import them automatically. To do this, go to Configure > Environments and click on the "Import from" button. The button name will be include the FQDN of the internal or external Capsule. Satellite will scan the Puppet master via the Capsule, and display a list of the detected changes. Select the changes you want to apply and select Update to apply the changes.

Note that the Capsule will only detect environments that contain one or more Puppet Classes, so ensure that at least one Puppet module containing a class has been deployed to the Puppet master.

Assigning a Puppet Environment to a Host

Navigate to Hosts > All Hosts, select a host by name from the Hosts list and then select Edit. On the Host tab you can select a Puppet Environment for the host. Selecting an environment will filter the classes on the Puppet Classes tab to help distinguish the classes in the selected environment.

You can mass-assign an environment to a group of hosts. Select the check boxes of the required hosts in the Hosts list, and then select Change Environment from the Select Action drop-down menu at the top of the page.

Assigning Puppet Environments to Host Groups

When creating a Host Group, the environment field is pre-populated by the environment that was automatically created by the associated Content View, if any.

By default, a user creating a new host and selecting the Host Group will automatically have the environment pre-selected. The user can change the environment of the new host.

3.8. Configuring Smart Class Parameters from Puppet Classes

Some module classes contain complex parameters, called Smart Class Parameters, that define a value for a key just as a simple parameter does, but allow conditional arguments, validation, and overrides for specific object types. Satellite 6 has the ability to import these parameterized classes and allow modification of such smart parameters. For more information on the types of parameters in Puppet, see Parameters in the Red Hat Satellite Host Configuration Guide.

For example, mymodule contains a parameter for the HTTP port of our web server. This parameter, httpd_port, is set to a default of 8120. However, a situation might occur where we need to use a different port for a provisioned system. Satellite 6 can override the httpd_port parameter during configuration. This provides an easy way to change the HTTP port on our web server.

This procedure requires the mymodule module to be uploaded to a Product and added to a Content View. This is because we need to edit the classes in the resulting Puppet environment. Alternatively, you can download and install another module as described in Chapter 3, Adding Puppet Modules to Red Hat Satellite 6.

  1. Navigate to Configure > Smart class parameters.
  2. A table appears listing all Smart Class Parameters from the classes in your Puppet modules. Enter httpd_port in the search field. Click on the httpd_port parameter.
  3. The options for the Smart Class Parameter appears. To allow overriding this parameter during provisioning, select the Override option.
  4. Selecting the Override option allows us to change the Key type and Default value. This is useful if we aim to globally change this value for all future configurations.

    The following key types are available:

    String

    The value is interpreted as a plain text string. For example, if your Smart Class Parameter sets the host name, the value is interpreted as a string:

    myhost.example.com
    Boolean

    The value is interpreted and validated as a true or false value. Examples include:

    True
    true
    1
    Integer

    The value is interpreted and validated as an integer value. Examples include:

    8120
    -8120
    Real

    The value is interpreted and validated as a real number value. Examples include:

    8120
    -8120
    8.12
    Array

    The value is interpreted and validated as a JSON or YAML array. For example:

    ["Monday","Tuesday","Wednesday","Thursday","Friday"]
    Hash

    The value is interpreted and validated as a JSON or YAML hash map. For example:

    {"Weekdays": ["Monday","Tuesday","Wednesday","Thursday","Friday"], "Weekend": ["Saturday","Sunday"]}
    YAML

    The value is interpreted and validated as a YAML file. For example:

    email:
      delivery_method: smtp
      smtp_settings:
        address: smtp.example.com
        port: 25
        domain: example.com
        authentication: none
    JSON

    The value is interpreted and validated as a JSON file. For example:

    {
      "email":[
        {
          "delivery_method": "smtp"
          "smtp_settings": [
            {
              "address": "smtp.example.com",
              "port": 25,
              "domain": "example.com",
              "authentication": "none"
            }
          ]
        }
      ]
    }

    For this example, leave the default as 8120.

  5. Selecting the Override option also exposes Optional Input Validator, which provides validation for the overridden value. For example, we can include a regular expression to make sure httpd_port is a numerical value. For our example, leave this section blank.
  6. Selecting the Override option also exposes Prioritize attribute order, which defines a hierarchical order of system facts, and Specify matchers. The matcher-value combinations determine the right parameter to use depending on an evaluation of the system facts. For our example, leave these sections with the default settings.
  7. Click Submit.

We now have an override value for the Smart Class Parameter httpd_port.

3.9. Using the Smart Variable Tool

Smart Variables are a tool for providing global parameters to the Puppet master for use with Puppet Classes that do not contain Smart Class Parameters. The same Smart Matcher rules are used for both Smart Variables and Smart Class Parameters.

Note

The Smart Variables tool was introduced as an interim measure before Puppet modules supported Smart Class Parameters. If you do not have a specific reason to use Smart Variables, Red Hat recommends that you use Smart Class Parameters instead as described in Section 3.8, “Configuring Smart Class Parameters from Puppet Classes”.

Before Smart Class Parameters were introduced, users who wanted to override a parameter where asked to rewrite their Puppet code to use a global parameter. For example:

class example1 {
  file { '/tmp/foo': content => $global_var }
}

For the above example, $global_var is set in the Smart Variables section of the web UI and the value is associated with the "example1" class. Although it is recommend to precede global variables with :: to restrict Puppet to search the global scope, their absence does not mean a variable is not a global variable.

With the introduction of Smart Class Parameters, the following form could be used:

class example2($var="default") {
  file { '/tmp/foo': content => $var }
}

For the above example, $var is set in the Smart Class Parameters section of the web UI and the value is associated with the "example2" class. If you see a variable defined in the class header, as in the above class example2($var="default"), then you can be sure that $var is a class parameter and you should use the Smart Class Parameter function to override the variable.

As demonstrated, Smart Variables require custom-designed modules using global-namespace parameters, rather than standard modules from the Puppet community, and the result is the same: text placed in '/tmp/foo' in the examples above. Consequently, there is no longer a reason to use Smart Variables except to support legacy modules.

Although Smart Variables are global variables, they are associated with a Puppet class and will only be sent to a host that has that specific Puppet Class assigned in Satellite. You can create a Smart Variable with any name, no validation is done in Satellite, but unless the associated Puppet module applied has a matching variable in its code, the Smart Variable will not be used.

Satellite adds the variable you create in Satellite to the Host YAML file. This file can be viewed in the web UI by navigating to Hosts > All Hosts, selecting the name of the host, and then clicking on the YAML button. Satellite sends the Host YAML file to the external node classifier (ENC), a function included with the Puppet master. When the Puppet master queries the ENC about a host, the ENC returns a YAML document describing the state of the host. This YAML document is based on data taken from Puppet manifests, but is subject to Smart Class Parameter overrides and any Smart Variables.

Applying a Smart Variable to a Host

As Smart Variables should only be used to support your custom Puppet modules previously modified to include a global parameter, the following example uses a simple example called anothermodule. The anothermodule Puppet module manifest is as follows:

class anothermodule {
   file { '/tmp/motd':
     ensure  => file,
     content => $::content_for_motd,
  }
}

This example will supply a value for the $::content_for_motd parameter.

  1. In the web UI, navigate to Configure > Classes.
  2. Select the name of the Puppet Class from the list.
  3. Click the Smart Variables tab. This displays a new screen. The left section contains a list of previously created parameters, if any. The right section contains the configuration options.
  4. Click Add Variable to add a new parameter.
  5. Enter the parameter in the Key field. In this example, content_for_motd.
  6. Edit the Description text box, for example Testing /tmp motd Text.
  7. Select the Key type of data to pass. Select string.
  8. Type a Default Value for the parameter. For example, No Unauthorized Use.
  9. Use the Optional Input Validator section to restrict the allowed values for the parameter. Choose a Validator type (either a list of comma separated values or a regular expression, regexp) and input the allowed values or regular expression code in the Validator rule field.
  10. Use the Prioritize attribute order section to set the order of precedence in which the host attributes or Facts are to be evaluated against the matchers (configured below). You can rearrange the entries in the list and add to the default list. To create a logical AND condition between matchers, arrange the names of the matchers on one line as a comma separated list.
  11. In the Specify matchers section, click Add Matcher to add a conditional argument. The attributes to match against should correspond to the entries in the Order list above. If no matcher is configured, then only the default value can be used. For example, if the desired value of the parameter is This is for Server1 for any host with a fully qualified domain name of server1.example.com, then specify the Match as fqdn=server1.example.com and the Value as This is for Server1.
  12. Click Submit to save your changes.

Chapter 4. Client and Server Settings for Configuration Management

An important part of Red Hat Satellite 6’s configuration process is making sure the Puppet clients (called Puppet agents) can communicate with the Puppet Server (called Puppet master) on either the internal Satellite Capsule or an external Satellite Capsule. This chapter examines how Red Hat Satellite 6 configures both the Puppet master and the Puppet agent.

4.1. Configuring Puppet on the Red Hat Satellite Server

Red Hat Satellite 6 controls the main configuration for the Puppet master on all Satellite Capsules. No additional configuration is required and it is recommended to avoid manually modify these configuration files. For example, the main /etc/puppet/puppet.conf configuration file contains the following [master] section:

[master]
    autosign       = $confdir/autosign.conf { mode = 664 }
    reports        = foreman
    external_nodes = /etc/puppet/node.rb
    node_terminus  = exec
    ca             = true
    ssldir         = /var/lib/puppet/ssl
    certname       = sat6.example.com
    strict_variables = false

    manifest       = /etc/puppet/environments/$environment/manifests/site.pp
    modulepath     = /etc/puppet/environments/$environment/modules
    config_version =

This section contains variables (such as $environment) that Satellite 6 uses to create configuration for different environments.

Some Puppet configuration options appear in the Satellite 6 web UI. Navigate to Administer > Settings and choose the Puppet subtab. This page lists a set of Puppet configuration options and a description of each.

4.2. Configuring Puppet agent on Provisioned Systems

As part of the provisioning process, Satellite 6 installs Puppet to the system. This process also installs the /etc/puppet/puppet.conf file that configures Puppet as an agent of the Puppet master on a chosen Capsule. This configuration file is stored as a provisioning template snippet in Satellite 6. Navigate to Hosts > Provisioning templates and click the puppet.conf snippet to view it.

The default puppet.conf snippet contains the following agent configuration:

[agent]
pluginsync      = true
report          = true
ignoreschedules = true
daemon          = false
ca_server       = <%= @host.puppet_ca_server %>
certname        = <%= @host.certname %>
environment     = <%= @host.environment %>
server          = <%= @host.puppetmaster %>

This snippet contains some template variables, which are:

  • @host.puppet_ca_server and @host.certname — The certificate and certificate authority for securing Puppet communication.
  • @host.environment — The Puppet environment on the Satellite 6 Server to use for configuration.
  • @host.puppetmaster — The host containing the Puppet master. This is either the Satellite 6 Server’s internal Capsule or an external Satellite Capsule.

Chapter 5. Applying Configuration on Clients

At this point, Satellite 6 Server’s Puppet ecosystem is configured and contains the mymodule module. We now aim to apply this module’s configuration to a registered system.

5.1. Applying Configuration on Clients During Provisioning

We first define a new host’s Puppet configuration using the following procedure. This procedure uses the uploaded mymodule as an example.

Applying Configuration on Clients During Provisioning

  1. Navigate to Hosts > New host.
  2. Click the Host tab. Enter a Name for the host and choose the organization and location for the system. Choose the Lifecycle Environment and its promoted Content View. This defines the Puppet environment to use for the configuration. Also choose a Puppet CA and Puppet Master from the Capsule Settings. The chosen capsule acts as the server that controls the configuration and communicates with the agent on the new host.
  3. Click the Puppet Classes tab and from the Available Classes section choose the Puppet classes that contain the configuration to apply. In our example, choose:

    • mymodule
    • mymodule:httpd
    • mymodule:app
  4. Choose the necessary options from the Operating System tab. These options depend on your own Satellite 6 infrastructure. Make sure the Provisioning templates option includes the Satellite Kickstart Default kickstart template. This template contains installation commands for the Puppet agent on the new host.
  5. Click the Parameters tab and provide any custom overrides to our Puppet class parameters. For example, modify the httpd_port from the mymodule to set your own custom port.
  6. After completing all provisioning options, click Submit.

The provisioning process begins. Satellite 6 installs the required configuration tools as part of the Satellite Kickstart Default provisioning template. This provisioning template contains the following:

<% if puppet_enabled %>
# and add the puppet package
yum -t -y -e 0 install puppet

echo "Configuring puppet"
cat > /etc/puppet/puppet.conf << EOF
<%= snippet 'puppet.conf' %>
EOF

# Setup puppet to run on system reboot
/sbin/chkconfig --level 345 puppet on

/usr/bin/puppet agent --config /etc/puppet/puppet.conf -o --tags no_such_tag <%= @host.puppetmaster.blank? ? '' : "--server #{@host.puppetmaster}" %> --no-daemonize
<% end -%>

This section performs the following:

  • Installs the puppet package from the Red Hat Satellite 6 Tools RPMs repository.
  • Installs the Puppet configuration snippet to the system at /etc/puppet/puppet.conf.
  • Enables the Puppet service to run on the system.
  • Run Puppet for the first time and apply the system configuration.

After the provisioning and configuration processes complete on the new host, access the host at the user-defined port in your web browser. For example, navigate to http://newhost.example.com:8120/. The following message should appear in your browser:

Congratulations

Your puppet module has correctly applied your configuration.

5.2. Applying Configuration to Existing Clients

You might aim to have Puppet configuration applied to an existing client not provisioned through Red Hat Satellite 6. In this situation, install and configure Puppet on the existing client after registering it to Red Hat Satellite 6.

Register your existing system to Red Hat Satellite 6. For information on registering existing hosts, see Registering a Host in the Red Hat Satellite Host Configuration Guide.

Important

The puppet package is part of the Red Hat Satellite 6 Tools repository. Ensure you enable this repository before you proceed.

To Install and Enable the Puppet Agent:

  1. Open a terminal console and log in as root.
  2. Install the Puppet agent:

    # yum install puppet
  3. Configure the Puppet agent to start at boot:

    • On Red Hat Enterprise Linux 6:

      # chkconfig puppet on
    • On Red Hat Enterprise Linux 7:

      # systemctl enable puppet

Configuring the Puppet Agent

  1. Configure the Puppet agent by changing the /etc/puppet/puppet.conf file:

    # vi /etc/puppet/puppet.conf
    [main]
        # The Puppet log directory.
        # The default value is '$vardir/log'.
        logdir = /var/log/puppet
    
        # Where Puppet PID files are kept.
        # The default value is '$vardir/run'.
        rundir = /var/run/puppet
    
        # Where SSL certificates are kept.
        # The default value is '$confdir/ssl'.
        ssldir = $vardir/ssl
    
    [agent]
        # The file in which puppetd stores a list of the classes
        # associated with the retrieved configuratiion.  Can be loaded in
        # the separate puppet executable using the --loadclasses
        # option.
        # The default value is '$confdir/classes.txt'.
        classfile = $vardir/classes.txt
        pluginsync = true
        report = true
        ignoreschedules = true
        daemon = false
        ca_server = satellite.example.com
        server = satellite.example.com
        environment = KT_Example_Org_Library_RHEL6Server_3
    
        # Where puppetd caches the local configuration.  An
        # extension indicating the cache format is added automatically.
        # The default value is '$confdir/localconfig'.
        localconfig = $vardir/localconfig
    Important

    Set the environment parameter to the host’s Puppet environment from the Satellite Server. The Puppet environment label contains the organization label, life-cycle environment, content view name, and the content view ID. To see a list of Puppet environments in the Satellite 6 web UI, navigate to Configure > Environments.

  2. Run the Puppet agent on the host:

    # puppet agent -t --server satellite.example.com
  3. Sign the SSL certificate for the Puppet client through the Satellite Server web interface:

    1. Log in to the Satellite Server through the web interface.
    2. Select Infrastructure > Capsules.
    3. Click Certificates to the right of the required host.
    4. Click Sign.
    5. Rerun the puppet agent command:

      # puppet agent -t --server satellite.example.com
Note

When the Puppet agent is configured on the host it will be listed under All Hosts but only when Any Context is selected as the host will not be assigned to an organization or location.

Chapter 6. Using Config Groups to Manage Puppet Classes

Red Hat Satellite includes the concept of Config Groups and Host Groups to enable building and managing groups of systems in a modular way.

Config Groups are a collection of Puppet Classes that you create to form building blocks for use in configuring Hosts and Host Groups. Config Groups are analogous to the community Puppet concept of Profiles, a Puppet Class that includes a collection of Puppet Classes to form a building block. Config Groups can be created and managed in the Satellite web UI.

Host Groups are both a collection of host servers and a container for the definition of a system, with a Content View, an assigned life cycle, and a set of Puppet modules. Host Groups are analogous to the community Puppet concept of Roles, a Puppet Class that includes a number of Profiles to build a system with a specific business role. Host Groups can be created and managed in the Satellite web UI, using the Hammer CLI, and by using the API.

Creating a Config Group

From the left-hand side context drop-down menu, select Any Organization and Any Location.

Navigate to Configure > Config groups.

Select New Config Group and enter a name, for example, TestConfGroup.

Select one or more Puppet Classes from the list of available classes.

Select Submit to apply the changes.

Once you have created a Config Group it will be available for selection on the Puppet Classes tab when configuring a Host or Host Group. For more information on creating Host Groups see Creating a Host Group in the Red Hat Satellite Host Configuration Guide and Creating a Host Group on Satellite Server in the Red Hat Satellite Provisioning Guide.

Chapter 7. Reviewing Puppet Reports in Red Hat Satellite 6

Puppet generates a report each time it applies a configuration. Provisioned hosts send this report to the Red Hat Satellite 6 Server. View these reports on the hosts details page.

Reviewing Puppet Reports in Red Hat Satellite 6

  1. Navigate to Hosts > All hosts.
  2. Click the Name of your desired host.
  3. Click the Reports button.
  4. Select a report to view.

Each report shows the status of each Puppet resource and its configuration applied to the host.