Lab 27: Ansible - Managing Inventory & Roles¶

Objective

Use static inventory with multiple nodes.
Create a role for database installation.
Apply the role via a playbook.

Step 0: Deploy another VM¶

Setup SSH Key Authentication same as before for new VM

On control node:

ssh-copy-id your_user_name@target-node-ip

# For Virtual Machines on AWS and using Amazon Linux the username is 'ec2-user`
# For Virtual Machines on AWS and using Ubunut the username is 'ubuntu'

Test:

ssh your_user_name@target-node-ip

(No password should be asked now ✅).

Step 1: Create Static Inventory with Groups¶

File: inventory.ini

[web]
192.168.1.20 ansible_user=ubuntu

[db]
192.168.1.30 ansible_user=ubuntu

Step 2: Create a Role for Database Server¶

Use Ansible Galaxy init:

ansible-galaxy init roles/dbserver

This creates:

roles/dbserver/
├── defaults/main.yml
├── handlers/main.yml
├── tasks/main.yml
├── templates/
├── vars/main.yml
└── ...

Step 3: Define Database Tasks¶

Edit roles/dbserver/tasks/main.yml:

---
- name: Install MySQL
  apt:
    name: mysql-server
    state: present
    update_cache: yes

- name: Ensure MySQL service is running
  service:
    name: mysql
    state: started
    enabled: yes

Step 4: Create Playbook to Use Role¶

File: dbserver.yml

---
- name: Configure Database Server
  hosts: db
  become: yes
  roles:
    - dbserver

Run:

ansible-playbook -i inventory.ini dbserver.yml

Step 5: Verify Database Setup¶

On DB node:

systemctl status mysql
mysql --version

Expected: MySQL running.