Quick reference sheet: Ansible tool

Ansible is an open-source IT automation tool that uses a simple language to automate tasks. It is agentless, which means that it does not require any software to be installed on the target hosts. Ansible is also push-based, which means that it pushes commands to the target hosts from the control node.

Here is a quick reference sheet for Ansible:

Getting started

• Install Ansible on the control node.

• Create an Ansible inventory file. This file lists the target hosts that you want to automate.

• Write Ansible playbooks. Playbooks are YAML files that define the tasks that you want to automate.

• Run Ansible playbooks. You can use the ansible-playbook command to run playbooks.

Basic commands

• ansible-playbook: Runs an Ansible playbook.

• ansible-ad-hoc: Runs an ad-hoc command on the target hosts.

• ansible-inventory: Lists the target hosts in the inventory file.

• ansible-gather-facts: Collects facts about the target hosts.

Useful modules

• file: Manages files and directories.

• service: Manages services.

• package: Manages software packages.

• user: Manages users and groups.

• shell: Runs shell commands.

Example playbook

YAML

---

- hosts: all

tasks:

- name: Update all packages

apt:

update_cache: yes

cache_valid_time: 3600

become: yes

- name: Install the nginx package

apt:

name: nginx

state: present

become: yes

- name: Start the nginx service

service:

name: nginx

state: started

become: yes

This playbook will update the package cache, install the nginx package, and start the nginx service on all of the target hosts.

Tips and tricks

• Use Ansible variables to make your playbooks more reusable.

• Use Ansible roles to organize your playbooks and make them easier to maintain.

• Use Ansible handlers to respond to events.

• Use Ansible conditional statements to control the flow of your playbooks.

For more information on Ansible, please see the official Ansible documentation: https://docs.ansible.com/ansible/latest/