Docker Automation with Ansible

Docker is a powerful platform for automating the deployment of applications in lightweight containers. Ansible is a popular automation tool used for configuration management, application deployment, and task automation. This lesson focuses on how to automate Docker container management using Ansible.

• Docker: A platform for developing, shipping, and running applications in containers.
• Ansible: An open-source automation tool that automates IT tasks such as configuration management, application deployment, and orchestration.
• Playbook: A YAML file containing a set of instructions that Ansible follows to perform tasks on managed nodes.
• Tasks: Individual actions defined in Ansible playbooks, which can include installing packages, managing services, or executing shell commands.

To get started with Docker automation using Ansible, follow these steps:

1. Install Docker on your target machine(s).
2. Install Ansible on your local machine or control node.
3. Ensure that you have SSH access to the target machine(s).

To install Docker, you can use the following commands:

sudo apt-get update
sudo apt-get install docker.io

To install Ansible, you can use:

sudo apt-get install ansible

Now, let's create a simple Ansible playbook to manage Docker containers. The following playbook demonstrates how to install Docker and run a simple Nginx container.

- hosts: all
  become: yes
  tasks:
    - name: Install Docker
      apt:
        name: docker.io
        state: present

    - name: Start Docker Service
      service:
        name: docker
        state: started

    - name: Pull Nginx Image
      docker_image:
        name: nginx
        tag: latest
        state: present

    - name: Run Nginx Container
      docker_container:
        name: my_nginx
        image: nginx
        state: started
        ports:
          - "80:80"

Save this playbook as docker_playbook.yml and run it using:

ansible-playbook -i inventory.ini docker_playbook.yml

Here are some best practices to follow when automating Docker with Ansible:

• Use version control for your playbooks.
• Organize playbooks and roles for maintainability.
• Test playbooks in a staging environment before deploying to production.
• Document your playbooks to help others understand your automation logic.