Demystifying Ansible Configuration: A Step-by-Step Guide to Editing /etc/ansible/hosts and /etc/ansible/ansible.cfg

Are you new to Ansible and wondering why running vi /etc/ansible/hosts and vi /etc/ansible/ansible.cfg opens an empty file? Don’t worry, you’re not alone! In this article, we’ll take you on a journey to understand the importance of these configuration files, and provide a comprehensive guide on how to edit them to get you started with Ansible.

What are /etc/ansible/hosts and /etc/ansible/ansible.cfg?

Before we dive into editing, let’s understand what these files do.

/etc/ansible/hosts

The /etc/ansible/hosts file is a crucial configuration file in Ansible that defines the hosts or nodes that Ansible will connect to and manage. This file is used to specify the inventory of hosts, which can be grouped into categories, and assigned specific variables and configurations.

/etc/ansible/ansible.cfg

The /etc/ansible/ansible.cfg file is the main configuration file for Ansible. It provides default settings for various aspects of Ansible, such as the inventory file location, the default module path, and the behavior of certain modules. This file is used to customize Ansible’s behavior and set default values for various parameters.

Why do these files open as empty?

When you run vi /etc/ansible/hosts and vi /etc/ansible/ansible.cfg, you might be surprised to see an empty file. This is because these files don’t exist by default on most systems. Ansible doesn’t create these files automatically; instead, it expects you to create and configure them according to your needs.

Creating and Editing /etc/ansible/hosts

Let’s create and edit the /etc/ansible/hosts file to add some hosts to our inventory.

Step 1: Create the hosts file

sudo touch /etc/ansible/hosts

This command creates an empty /etc/ansible/hosts file.

Step 2: Add hosts to the inventory

Edit the /etc/ansible/hosts file using your favorite editor (e.g., vi, nano, or emacs).

sudo vi /etc/ansible/hosts

Add the following content to the file:

[webservers]
node1 ansible_host=192.168.1.10
node2 ansible_host=192.168.1.20

[dbservers]
node3 ansible_host=192.168.1.30
node4 ansible_host=192.168.1.40

In this example, we’ve created two groups: webservers and dbservers. Each group contains two hosts with their corresponding IP addresses. You can add more hosts and groups as needed.

Creating and Editing /etc/ansible/ansible.cfg

Now, let’s create and edit the /etc/ansible/ansible.cfg file to customize Ansible’s behavior.

Step 1: Create the ansible.cfg file

sudo touch /etc/ansible/ansible.cfg

Step 2: Edit the ansible.cfg file

Edit the /etc/ansible/ansible.cfg file using your favorite editor.

sudo vi /etc/ansible/ansible.cfg

Add the following content to the file:

[defaults]
inventory = /etc/ansible/hosts
remote_user = ansible
ask_pass = True

In this example, we’ve set the default inventory file to /etc/ansible/hosts, specified the remote user as ansible, and enabled password prompting with ask_pass = True. You can customize these settings and add more as needed.

Verifying the Configuration

After creating and editing the /etc/ansible/hosts and /etc/ansible/ansible.cfg files, let’s verify that Ansible is using these configurations.

Step 1: Check the inventory

ansible -i /etc/ansible/hosts --list-hosts

This command will list the hosts in your inventory, grouped by category.

Step 2: Run a simple Ansible command

ansible -m ping all

This command will ping all hosts in your inventory and return the results.

Common Issues and Troubleshooting

Here are some common issues you might encounter when working with /etc/ansible/hosts and /etc/ansible/ansible.cfg:

Issue	Solution
Error: “Error: /etc/ansible/hosts: No such file or directory”	Create the /etc/ansible/hosts file using the steps above.
Error: “Error: /etc/ansible/ansible.cfg: No such file or directory”	Create the /etc/ansible/ansible.cfg file using the steps above.
Ansible is not using the custom inventory file	Verify that the inventory parameter is set correctly in the /etc/ansible/ansible.cfg file.

Conclusion

In this article, we’ve demystified the mysteries of /etc/ansible/hosts and /etc/ansible/ansible.cfg. We’ve provided a step-by-step guide on how to create and edit these files, and troubleshoot common issues. With these configurations in place, you’re ready to start using Ansible to automate your infrastructure.

Remember, practice makes perfect! Experiment with different inventory configurations, custom modules, and playbooks to unlock the full potential of Ansible.

Additional Resources

• Ansible Documentation: Inventory
• Ansible Documentation: Configuration
• Ansible GitHub: Ansible Repository

Happy automating!

Frequently Asked Question

Getting stuck with Ansible configuration files? Don’t worry, we’ve got you covered!