Ansible Series

When I joined to ORO, there are some Project that were apply the Ansbile to setup the server. After that I tried to use Ansible to improve the automation work like setup the server, deploy the application, etc. So I will write some post to share my experience with Ansible.

Today, when I am working on my HomeLab, The VM normally created and deleted. So I need to setup the VM quickly. So I will use Ansible to setup the VM.

Install Ansible on the Working Machine.

I install the Ansbile on 1 main Debian VM. In this machine I can do everything with Ansible.

sudo apt-add-repository ppa:ansible/ansible

sudo apt update

sudo apt install ansible

Setup the inventory file

The inventory file is the file that contain the list of the server that we want to manage. In this file we can define the group of the server, the variable for each server, etc.

[homeserver]
svr01 ansible_host=192.168.1.253 ansible_user=khoa
svr02 ansible_host=192.168.1.176 ansible_user=khoa
svr03 ansible_host=192.168.1.155 ansible_user=khoa

svr01 is alias, ansible_user=khoa is host variable

I have 3 Ubuntu VM that I want to setup the Kubernetes cluster. So I will create the inventory file with the name inventory and put the content above to the file.

Then, Check the inventory is correct.

ansible-inventory -i inventory --list

The output should be like this:

{
  "_meta": {
    "hostvars": {
      "svr01": {
        "ansible_host": "192.168.1.253",
        "ansible_user": "khoa"
      },
      "svr02": {
        "ansible_host": "192.168.1.176",
        "ansible_user": "khoa"
      },
      "svr03": {
        "ansible_host": "192.168.1.155",
        "ansible_user": "khoa"
      }
    }
  },
  "all": {
    "children": ["ungrouped", "homeserver"]
  },
  "homeserver": {
    "hosts": ["svr01", "svr02", "svr03"]
  }
}

We can have multiple group in the inventory file. For example, I want to create the group for the Kubernetes master and worker. So I will add the content below to the inventory file.

[masters]
master1 ansible_host=203.0.113.111


[workers]
worker1 ansible_host=203.0.113.113
worker2 ansible_host=203.0.113.114

[masters:vars]
ansible_user=root

[workers:vars]
ansible_user=worker

Running the command to check the connection to the server.

ansible all -i inventory -m ping

Add the Playbook

This is the simple playbook that will install the docker on the server and run the simple container

- hosts: homeserver
  become: true
  vars:
    container_count: 4
    default_container_name: docker
    default_container_image: ubuntu
    default_container_command: sleep 1d
    ansible_sudo_pass: "[root sudo password]" //temporary push the password on the file to test out the command
  tasks:
    - name: Install aptitude
      apt:
        name: aptitude
        state: latest
        update_cache: true

    - name: Install required system packages
      apt:
        pkg:
          - apt-transport-https
          - ca-certificates
          - curl
          - software-properties-common
          - python3-pip
          - virtualenv
          - python3-setuptools
        state: latest
        update_cache: true
    - name: Add Docker GPG apt Key
      apt_key:
        url: https://download.docker.com/linux/ubuntu/gpg
        state: present

    - name: Add Docker Repository
      apt_repository:
        repo: deb https://download.docker.com/linux/ubuntu jammy stable
        state: present

    - name: Update apt and install docker-ce
      apt:
        name: docker-ce
        state: latest
        update_cache: true

    - name: Install Docker Module for Python
      pip:
        name: docker

    - name: Pull default Docker image
      community.docker.docker_image:
        name: "{{ default_container_image }}"
        source: pull

    - name: Create default containers
      community.docker.docker_container:
        name: "{{ default_container_name }}{{ item }}"
        image: "{{ default_container_image }}"
        command: "{{ default_container_command }}"
        state: present
      with_sequence: count={{ container_count }}

Execute the playbook

ansible-playbook -i inventory playbook.yaml