Introduction

In traditional Networking, network engineers had to log into each server to make changes manually. It was tedious, error-prone, and honestly, pretty boring. Then Ansible modules came, and everything changed.

Ansible modules are essential for IT automation. They are small, specialized tools that do one thing really well. Whether you need to install software, manage users, or configure networks, there’s probably a module for that. With ansible, tasks become more efficient and consistent.

In this guide, we will walk you through everything you need to know about Ansible modules. We will cover what they are, how they work, and most importantly, how you can use them to make your life easier. We will also discuss Ansible module list along with examples.

And if you’re serious about taking your automation skills to the next level, learning how Ansible works alongside Terraform can be a game changer. That’s why many professionals choose to enroll in a combined Ansible and Terraform course to build real-world automation and infrastructure provisioning skills. Let us first understand what ansible modules are.

Let us first understand what Ansible Modules are.

What Are Ansible Modules?

Ansible modules are essentially small programs that performs a specific task on a remote system. You use different modules for different automation tasks.

The magic happens when you combine these modules in what we call “playbooks.” Just as a recipe instructs on how to mix ingredients and in what order, a playbook instructs Ansible on which modules to execute and in what sequence. It is quite simple once you get used to it.

A special property of modules is that they are idempotent. It implies that you can rerun the same task any number of times, and you will continue to receive an identical output. For example, when you command a module to create a user account, it will create it only once. When you run again, it will not generate a duplicate – it will determine that the user indeed exists and proceed. It’s designed to be safe to run over and over again.

Now that you have a good understanding of modules in Ansible, let’s discuss how these modules actually work.

How Ansible Modules Work?

Here’s something that might surprise you: Ansible modules are just regular programs. They can be written in any language, though most are written in Python. When you run an Ansible playbook, here’s what happens behind the scenes:

• Ansible reads your playbook and figures out which modules need to run
• It copies the module to the target server
• The module runs on the remote server and does its job
• The module reports back what it did (or didn’t do)
• Ansible cleans up by removing the module from the remote server

Ansible doesn’t require any special software to be installed on your servers; it simply needs SSH access. This makes it much easier to get started compared to other automation tools.

One advantage of modules is how they handle errors. If something goes wrong, the module will stop and tell you exactly what happened. This makes debugging much easier than trying to figure out what went wrong in a long shell script.

Below, we have discussed different types of Modules in Ansible in detail, along with examples.

Types of Ansible Modules

Not all modules are created equal. There are different types, and understanding the differences will help you know where to look for what you need.

Core Modules: The Foundation

Core modules are maintained by the core Ansible team and come bundled with every Ansible installation. They cover the most common tasks you will encounter in system administration.

Some of the most useful core modules include:

• File operations: copy, file, template, lineinfile
• Package management: apt, yum, dnf, pip
• Service management: service, systemd
• User management: user, group
• System commands: command, shell

Use these modules in almost every playbook you write. They are reliable, well-documented, and cover probably 80% of what you will need to do.

Collections: The Modern Way

In recent years, Ansible has moved to a collection-based system. Collections are bundles of modules, plugins, and other content that are packaged together. This makes it easier to distribute and maintain community-contributed content.

The most important collection is ansible.builtin, which contains all the core modules. But there are hundreds of other collections available on Ansible Galaxy. For example:

• community.general: A vast collection of modules for various tasks
• amazon.aws: Modules for managing AWS resources
• cisco.ios: Modules for managing Cisco network devices
• kubernetes.core: Modules for managing Kubernetes clusters

When you look for a specific module, you usually start with the built-in ones. If you can’t find what you need, you will search Ansible Galaxy for collections.

Custom Modules: Making Your Own

Sometimes you need to do something that no existing module can handle. That is where custom modules can be used. There is no limit to what you can write your own module to do.

The truth is, writing your own modules is not something that you are going to do frequently. And when you need it, it is extremely powerful. Having a custom module is simpler than you might think. The basic structure is pretty simple:

• Accept some parameters
• Do something on the system
• Return some JSON output

If you are comfortable with Python, you can probably write a simple custom module in an hour or two.

For a better understanding, let’s now discuss some real-world use cases of modules in Ansible.

Real-World Use Cases of Ansible Modules

Alright, let’s discuss real-world use cases of Ansible Modules. Here’s how you can actually use these modules in your day-to-day work.

System Administration

This is where Ansible really shines. If you are a system administrator, you know the drill – lots of tedious, repetitive tasks that need to be done. Ansible can handle most of it for you.

• User Management: Picture this – your boss walks in and says you need to add a new user to 100 servers. Your heart sinks because you know it’s going to take all day. However, with Ansible’s user module, you can accomplish this in under 10 minutes.
• Keeping Servers Updated: Security patches are non-negotiable these days. You can’t afford to fall behind. With the apt or yum module, you can build a playbook that hits all your servers at once. Set it to run automatically every week. No more staying late to manually patch servers.
• Firewall Rules: Opening ports used to be a pain. Log into each server, remember the right commands, and hope you don’t lock yourself out. Now you can use the ufw module for Ubuntu boxes or firewalld for CentOS. Push the changes everywhere at once and call it a day.

Applications Deployment

App deployment can be tricky. There are so many moving parts – files to copy, databases to update, services to restart. Miss one step and everything breaks. Ansible keeps it all organized.

• Setting Up Web Servers: Earlier, it took days to set up a web server. Now you can write a playbook that installs Nginx, copies the website files with the copy module, and handles all the configuration with the template module. What used to take days now takes minutes.
• Database Management: Creating databases and users used to mean logging into each database server individually. Not anymore. There are modules for MySQL, PostgreSQL, and pretty much any database you can think of. Set permissions, create users, whatever you need.
• CI/CD Integration: This is where things get really interesting. When developers push code, Jenkins (or whatever CI tool you use) can start an Ansible playbook automatically. The new version gets deployed without anyone lifting a finger.

Cloud Provisioning

Everything’s in the cloud these days. Ansible plays nice with all the big providers – AWS, Azure, Google Cloud, you name it.

• Launch Servers: Need a new server on AWS? The ec2_instance module has you covered. Tell it what size you want, which OS, and boom – you’ve got a server. No clicking around in web consoles.
• Network Management: Virtual private clouds, subnets, security groups – Ansible can handle all of it. This is huge for keeping your cloud setup consistent. No more wondering if someone forgot to configure something properly.
• Load Balancers and Databases: Load balancers, managed databases, all that good stuff. Ansible has modules for these, too. The AWS ELB module for load balancers and RDS for databases. It’s all there.

Network Automation

Here’s something people don’t always think about – Ansible works great with network gear, too. Routers, switches, firewalls.

• Backing Up Configs: Now, the playbook can log into every network device and grab the config. Runs every night like clockwork.
• Applying configuration Changes: Need to update a VLAN on 50 switches? Used to be a nightmare. Log into each one, make the change, and hope you didn’t typo anything. Now you can write the change once in a playbook and push it everywhere. Saves hours and prevents mistakes.

The best part about all this? You write the playbook once, and it works forever. No more doing the same thing over and over.

Here’s a comprehensive table of different module categories and their use cases:

Module Category	Description	Common Use Cases	Popular Modules
Cloud Modules	Manage cloud infrastructure and services	Launch EC2 instances, create storage buckets, manage load balancers	ec2_instance, s3_bucket, azure_rm_virtualmachine
Database Modules	Manage databases and database objects	Create databases, manage users, run queries, backup data	mysql_db, postgresql_user, mongodb_user
File System Modules	Handle file and directory operations	Copy files, create directories, manage permissions, search files	copy, file, template, find
Identity Modules	Manage users, groups, and authentication	Create user accounts, manage SSH keys, configure LDAP	user, group, authorized_key
Inventory Modules	Manage dynamic inventory sources	Pull inventory from cloud providers, CMDB systems	aws_ec2, azure_rm
Messaging Modules	Handle message queues and notifications	Send emails, manage RabbitMQ, send Slack notifications	mail, rabbitmq_queue, slack
Network Modules	Configure network devices and settings	Configure routers, manage VLANs, set up firewalls	ios_config, nxos_vlan, ufw
Packaging Modules	Install and manage software packages	Install packages, manage repositories, handle dependencies	apt, yum, pip, npm
Remote Management Modules	Control remote systems and services	Restart services, run commands, manage processes	service, systemd, command
Source Control Modules	Manage version control systems	Clone repositories, checkout branches, manage tags	git, svn
System Modules	Handle system-level operations	Mount filesystems, manage cron jobs, configure kernel parameters	mount, cron, sysctl
Utilities Modules	Provide helper functions and utilities	Debug playbooks, pause execution, set facts	debug, pause, set_fact
Web Infrastructure Modules	Manage web servers and applications	Configure Apache, manage SSL certificates, handle load balancers	apache2_module, acme_certificate

This table gives you a good overview of a detailed Ansible module list. Each category has dozens of modules, so there’s usually something for whatever you need to do.

Examples of Ansible Modules

Let’s get hands-on with some examples. We will walk you through each use case with simple playbooks you can try.

File Module

Say you want to create a directory for logs:

- name: Create a log directory
file:
path: /var/log/myapp
state: directory
mode: '0755'

This makes a directory at /var/log/myapp with standard permissions. Run it again? No problem—it won’t redo what’s already there.

To delete a file:

- name: Delete an old log
file:
path: /var/log/old.log
state: absent

Apt Module

Installing Nginx on Ubuntu? Here’s how:

- name: Install Nginx
apt:
name: nginx
state: present

This checks if Nginx is installed and adds it if not. Want to update everything?

- name: Update all packages
apt:
upgrade: dist

It’s like running apt-get upgrade across your servers.

Service Module

To start Nginx and make it boot-friendly:

- name: Start and enable Nginx
service:
name: nginx
state: started
enabled: yes

Need a quick restart?

- name: Restart Nginx
service:
name: nginx
state: restarted

User Module

Creating a user named “sarah” with sudo rights:

- name: Add Sarah
user:
name: sarah
state: present
groups: sudo
shell: /bin/bash

To remove her later:

- name: Remove Sarah
user:
name: sarah
state: absent

Clean and simple.

Template Module

Deploying an Nginx config file:

- name: Set up Nginx config
template:
src: /path/to/nginx.conf.j2
dest: /etc/nginx/nginx.conf
notify: restart nginx

This uses a template file (.j2) and restarts Nginx if it changes.

EC2 Instance Module

Launching an AWS EC2 instance:

- name: Launch an EC2 instance
ec2_instance:
name: "web-server"
key_name: "my-key"
instance_type: "t2.micro"
image: "ami-123456"
wait: yes

This spins up a small server and waits till it’s ready.

IOS Config Module

Configuring a Cisco router:

- name: Set up router interface
ios_config:
lines:
- description Managed by Ansible
- ip address 192.168.1.1 255.255.255.0
parents: interface GigabitEthernet0/0

This sets an IP and description on the router’s interface.

Advanced Module Usage

Ready to level up? Here are some pro tricks for using modules.

Looping Over Tasks

Install multiple packages at once with a loop:

- name: Install several packages
package:
name: "{{ item }}"
state: present
loop:
- nginx
- git
- curl

This installs all three in one shot.

Waiting for Something

Need to pause until a server’s ready? Use `wait_for`:

- name: Wait for port 80 to be open
wait_for:
port: 80
state: started

This waits until port 80 is active.

Checking Conditions

Run a task only if something’s true:

- name: Restart if needed
service:
name: nginx
state: restarted
when: restart_needed | bool

This restarts `nginx` only if `restart_needed` is true.

Below, we have discussed some of the best practices that you can follow for better utilization of modules in Ansible.

Best Practices for Using Ansible Modules

In order to make the most of Ansible modules, here are some of my tips that I have acquired over time:

• Name Your Tasks: Task name is optional, but it is a good idea to always name your tasks using the name attribute. It will also make reading and debugging your playbooks much more convenient. When you execute a playbook, Ansible displays the name of the task that it is executing.
• Use Variables: Avoid hardcoded values in your playbooks. Rather than doing it, use variables. To give a specific example, rather than hardcoding a username of Dave in the application, you can use a variable such as {{ developer_user }}. This makes your playbooks more reusable and flexible.
• Always see what modules already exist: Before you consider writing a custom module, always check in Ansible Galaxy to see whether someone has done one similar to what you need.
• Read documentation: Each Ansible module has documentation on how to use all of its options and examples as well. When you open a new module, spend some time reading the documentation. It will prevent you from tons of headaches later. ansible-doc <module_name> will give you the documentation of any module on your command line.

The Future of Ansible Modules

The Ansible ecosystem is constantly evolving. Here are some trends:

• More Cloud Integration: Every major cloud provider now has comprehensive Ansible collections. This makes it easier than ever to manage cloud infrastructure as code.
• Better Kubernetes Support: As more organizations adopt Kubernetes, the kubernetes.core collection is becoming increasingly important. You can now manage entire Kubernetes clusters with Ansible.
• Enhanced Security Features: New modules are being developed with security in mind. Features like automatic credential rotation and compliance checking are becoming more common.
• Improved Windows Support: While Ansible started as a Linux tool, Windows support has improved dramatically. There are now hundreds of modules specifically for Windows environments.

Frequently Asked Questions

Q1. What are the modules of Ansible?

Ansible modules are ready-made tools that handle specific jobs like installing software or managing files. They run tasks on servers automatically, saving time and effort.

Q2. What is Ansible and its use?

Ansible automates IT tasks like server setup and app deployment. It works without extra software on remote machines, making management faster and more reliable.

Q3. What is the difference between Ansible modules and plugins?

Modules run on remote servers and do actual work, like installing packages. Plugins run locally and help Ansible process data, connect to systems, or format output.

Q4. How to create modules in Ansible?

Write a Python script that takes inputs, performs actions, and returns JSON results. Test it, then add it to Ansible’s module library for reuse. Keep it simple and efficient.

Conclusion

Ansible modules can be very effective tools that can change the way you handle your infrastructure. They remove the monotony out of repeatable jobs and eliminate fail-prone complex operations and automate them.

The secret behind the successful use of Ansible is to begin small. Find a single simple task which you repeat and then automate that thing with a playbook. Once you feel comfortable, you will be able to work with more complicated situations.