The Ultimate Ansible and Docker Cheat Sheet

In the fast-paced world of DevOps and containerization, mastering tools like Ansible and Docker is essential for streamlining deployment processes, managing infrastructure, and ensuring seamless application delivery. This comprehensive cheat sheet aims to provide you with a quick reference guide for both Ansible and Docker, covering essential commands, tips, and step-by-step instructions to enhance your efficiency in handling these powerful tools.

1. Ansible Basics:
   Ansible is an open-source automation tool that simplifies configuration management and application deployment. Here are some fundamental commands to get you started:

   • ansible --version: Check the installed Ansible version.
   • ansible-playbook playbook.yml: Execute an Ansible playbook.
   • ansible-galaxy init role_name: Create a new Ansible role.
   • ansible-vault encrypt file.yml: Encrypt sensitive data in a YAML file.

2. Docker Essentials:
   Docker revolutionized containerization, allowing for easy packaging and distribution of applications. Here are key Docker commands every developer and system administrator should know:

   • docker --version: Display the installed Docker version.
   • docker run image_name: Start a container from an image.
   • docker ps -a: List all containers, including stopped ones.
   • docker build -t image_name .: Build a Docker image from a Dockerfile.

3. Integrating Ansible with Docker:
   Combining Ansible with Docker can significantly enhance automation capabilities. Follow these steps to integrate both tools seamlessly:

   a. Install Docker on Target Hosts:
   Use Ansible to install Docker on your target hosts with the following playbook:

   ---
   - hosts: target_hosts
     tasks:
       - name: Install Docker
         apt:
           name: docker.io
           state: present
   

   b. Deploy Docker Containers with Ansible:
   Leverage Ansible to deploy Docker containers by defining tasks in your playbook. For example:

   ---
   - hosts: target_hosts
     tasks:
       - name: Start Nginx Container
         docker_container:
           name: nginx_container
           image: nginx
           state: started
   

4. Advanced Tips and Tricks:
   Enhance your Ansible and Docker proficiency with these advanced tips:

   • Dynamic Inventory:
     Utilize dynamic inventories in Ansible to automatically discover and manage hosts, especially in dynamic cloud environments.

   • Docker Compose:
     Simplify multi-container application deployment with Docker Compose. Define services, networks, and volumes in a docker-compose.yml file for easier orchestration.