Creating Tasks | Tasks And Handlers

Introduction

In Ansible, tasks are the fundamental units of work. They are used to define the state that you want to enforce on your managed nodes. This tutorial will guide you through the process of creating tasks in Ansible from start to finish, with detailed explanations and examples.

Understanding Tasks

A task in Ansible is a single action that is performed on a managed node. Tasks can include actions like installing packages, copying files, and restarting services. Each task is defined using a YAML syntax and includes a name and a module with its associated parameters.

Basic Structure of a Task

The basic structure of a task in Ansible is as follows:

- name: 
  : 
    :

Here, name is a human-readable description of the task, module is the Ansible module to be used, and parameter and value are the arguments for the module.

Creating a Simple Task

Let's create a simple task that installs the Apache web server on a managed node. Here is the YAML code for the task:

- name: Install Apache web server
  apt: 
    name: apache2
    state: present

In this example, we use the apt module to install the apache2 package, and we ensure that its state is present.

Running the Task

To run the task, you need to include it in a playbook. Here is an example playbook that includes the task we just created:

---
- hosts: webservers
  tasks:
    - name: Install Apache web server
      apt: 
        name: apache2
        state: present

Save this playbook to a file named install_apache.yml. To execute the playbook, use the following command:

ansible-playbook install_apache.yml

This command will run the playbook and apply the task to all hosts in the webservers group.

Verifying Task Execution

After running the playbook, you can verify that the task was executed successfully by checking the status of the Apache web server on the managed node:

systemctl status apache2

You should see output indicating that the Apache service is active and running.

Advanced Task Example

Let's create a more advanced task that does the following:

Updates the package cache
Installs Apache web server
Ensures Apache is enabled and started

Here is the YAML code for the advanced task:

---
- name: Setup Apache web server
  hosts: webservers
  tasks:
    - name: Update the apt package cache
      apt: 
        update_cache: yes
    
    - name: Install Apache web server
      apt: 
        name: apache2
        state: present
    
    - name: Ensure Apache is enabled and started
      systemd: 
        name: apache2
        enabled: yes
        state: started

This playbook includes three tasks. The first task updates the package cache using the apt module. The second task installs the Apache web server, and the third task ensures that Apache is enabled and started using the systemd module.

Conclusion

In this tutorial, we have covered the basics of creating tasks in Ansible. We started with a simple task to install the Apache web server and then moved on to a more advanced example that includes multiple tasks. By following these examples, you should now have a solid understanding of how to create and run tasks in Ansible.

Creating Tasks in Ansible