Puppet – Automating Infrastructure Configuration

What is Puppet?

Puppet is an open-source configuration management tool that automates the provisioning, configuration, and management of infrastructure. It ensures that your systems are configured consistently and correctly according to predefined policies.

Why is Puppet a Configuration Management Tool?

Automates Setup: Ensures systems are consistently configured.
Infrastructure as Code: Uses a declarative language to define configurations.
Consistency: Enforces policies across systems, reducing configuration drift.

Use Cases

Provisioning: Automate setup of new servers.
Configuration: Maintain consistent system configurations.
Deployment: Automate software installations and updates.
Compliance: Ensure systems meet regulatory standards.

Dependencies

Puppet Agent: Installed on managed nodes.
Puppet Master: Central server distributing configurations.
Modules/Manifests: Code defining resource states.

Setting Up Puppet

To set up Puppet, you need a master server (Puppet Master) and one or more agent servers (Puppet Agents). Here’s a simplified guide:

Initial Setup

Update your repositories:

         sudo apt update

     sudo apt upgrade

Install Docker:

 sudo apt install docker.io

Pull the Puppet image:

sudo docker pull puppet

Create the Puppet Master container:

 sudo docker run --name puppet-master -it puppet7

Start the Docker service:

  sudo systemctl start docker

Run the Puppet Master container:

sudo docker start puppet-master

Check if the container is running:

```
 sudo docker ps -a
```
Installing Puppet Server:
```
  apt install puppetserver
```
Enter the container and install necessary utilities:
```
 apt install vim net-tools
```
If you encounter issues with broken packages, run the following commands:
```
  apt update && sudo apt upgrade
```
comm : apt --fix-broken install

  apt clean

 apt autoremove && sudo apt-get autoremove

```
  apt-get install puppet-agent
```

 apt-get install puppet-module-puppetlabs-mailalias-core

```
 apt-get install puppetserver
```

else

Check the Java version:
```
  java -version
```
(Note : Adjust Java configuration if necessary to manage system memory usage)

Check Puppet service:
```
  netstat -ntulp
```
(If you see port 8140, it means Puppet is listening to all ports.)

Set up the Certificate Authority:
```
   /opt/puppetlabs/bin/puppetserver ca setup
```
**

Check system information:**
```
  facter -p
```
Find the Fully Qualified Domain Name (FQDN):
```
  facter -p | grep fqdn
```
Create a .pp file for Puppet configurations:
```
   puppet apply filename.pp
```

Creating the Puppet Agent

Create the Puppet Agent container using the same image:

      sudo docker run --name puppet-agent01 -it puppet

(Note : Start and run the Puppet Agent container as described earlier)

Install Puppet Agent in the container:

      apt install puppet-agent

Establishing Communication

Update /etc/hosts with IP and FQDN:

     vi /etc/hosts  (Note: Add the IP and FQDN at the end of the file)

Run commands in the Puppet Agent container to establish communication with the master:

      /opt/puppetlabs/bin/puppetserver ca setup

In the Puppet Master container, configure autosign in /etc/puppetlabs/puppet/puppet.conf:

autosign = true

In the Puppet Agent container, test the connection to the Puppet Master:

```
     puppet agent --test puppet_masterfqdn
```
Managing Puppet Policies for both(master & agent )

In the Puppet Master container, navigate to:
```
 cd /etc/puppetlabs/code/environments/production/manifests/
```
(Note : In this directory create this file )

Create init.pp and site.pp files to define policies and configurations.

In the Puppet Agent container, run the following command to apply policies from the master:

To run again you have to run this command again and again :
```
  puppet agent --test puppet_masterfqdn
```
P.S.

If you spot any mistakes, please don't hesitate to point them out. We're all here to learn together! 😊

Haris
FAST (NUCES)
BS Computer Science | Class of 2027

📌 GitHub: https://github.com/Zenvila
📌 LinkedIn: https://www.linkedin.com/in/haris-shahzad-7b8746291/
📌 Member: COLAB (Research Lab)