024 Install Required Packages

Tech Tutorial: Install and Configure an Ansible Control Node #

Introduction #

In this tutorial, we will cover the essential steps to install and configure an Ansible control node specifically on a Red Hat Enterprise Linux (RHEL) system. Ansible is a powerful automation tool widely used for configuration management, application deployment, and task automation. The control node is the machine where Ansible is installed and from which all tasks and playbooks will be run.

This guide is tailored for those preparing for the Red Hat Certified Engineer (RHCE) exam, focusing on the exam objective of installing required packages for setting up an Ansible control node on RHEL.

Prerequisites #

  • A RHEL 8 system with administrative privileges.
  • Access to a terminal or command line interface.
  • An active subscription to Red Hat or access to RHEL packages.

Step-by-Step Guide #

Step 1: Update Your System #

Before installing any new packages, it is a good practice to ensure your system is up-to-date. This can be achieved by using the dnf package manager, which is the default on RHEL 8.

sudo dnf update -y

Step 2: Install the EPEL Repository #

Ansible packages are available under the Extra Packages for Enterprise Linux (EPEL) repository. Install the EPEL release package using dnf.

sudo dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm -y

Step 3: Install Ansible #

Once the EPEL repository is enabled, you can proceed to install Ansible.

sudo dnf install ansible -y

To verify the installation of Ansible, run:

ansible --version

This command will display the version of Ansible installed along with some configuration details.

Step 4: Configure SSH Access #

Ansible communicates with the nodes it manages using SSH. It is ideal to set up SSH key-based authentication for seamless operation.

  1. Generate an SSH key pair on the control node:

    ssh-keygen -t rsa -b 2048

    Follow the prompts to specify the file in which to save the key and enter a passphrase if desired.

  2. Copy the public key to the managed nodes:

    ssh-copy-id user@managed-node-ip

    Replace user and managed-node-ip with the appropriate username and IP address of the managed node. You will be prompted to enter the user’s password on the managed node.

Step 5: Test Ansible Configuration #

Create a simple inventory file named hosts in your working directory and add the managed node’s IP under the [servers] group.

[servers]
192.168.1.100

Run a simple Ansible command to check if the control node can communicate with the managed node(s):

ansible all -i hosts -m ping

If everything is set up correctly, you should receive a SUCCESS message.

Conclusion #

Setting up an Ansible control node on RHEL involves installing the necessary packages from the EPEL repository, configuring SSH for remote communication, and validating the setup by testing connectivity to your managed nodes. With these steps complete, your control node is ready to automate tasks across your infrastructure.

As you prepare for the RHCE exam, ensure you’re comfortable with managing packages via dnf, handling repositories, and configuring SSH, as these are foundational skills not only for Ansible but for RHEL system administration in general.