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Aisalkyn Aidarova
Aisalkyn Aidarova

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LAB: 2 EC2 Servers + Group-Based Deployment

#devops #automation #tutorial #aws

Objective

  • Inventory groups
  • Deploy different software to different servers
  • Run playbook against specific group
  • Use variables per group
  • Understand real-world environment separation

Architecture

Image

Image

Image

Image

Control Node (Mac)
↓ SSH
EC2-1 → Web Server
EC2-2 → DB Server

Step 1 — Launch 2 EC2 Instances

Both:

  • Ubuntu 22.04
  • Port 22 open
  • Port 80 open (for web)
  • Same key pair

Example IPs:

Web: 3.141.22.178
DB: 3.141.25.200

Step 2 — Create Inventory with Groups

Edit inventory.ini

[web]
3.141.22.178 ansible_user=ubuntu ansible_ssh_private_key_file=~/Downloads/pem/key.pem

[db]
3.141.25.200 ansible_user=ubuntu ansible_ssh_private_key_file=~/Downloads/pem/key.pem
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Test:

ansible all -i inventory.ini -m ping
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Both should return pong.

Step 3 — Create Group-Based Playbook

Create:

vim multi-server.yml
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Paste:

- name: Configure Web Server
  hosts: web
  become: yes

  tasks:
    - name: Install nginx
      apt:
        name: nginx
        state: present

    - name: Start nginx
      service:
        name: nginx
        state: started
        enabled: yes


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

  tasks:
    - name: Install mysql
      apt:
        name: mysql-server
        state: present

    - name: Start mysql
      service:
        name: mysql
        state: started
        enabled: yes
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Step 4 — Run Playbook 

ansible-playbook -i inventory.ini multi-server.yml
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Students will observe:

  • Web server installs nginx only
  • DB server installs MySQL only
  • Separate execution blocks

Step 5 — Verify

Web server:

http://3.141.22.178
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Should show nginx.

SSH into DB server:

systemctl status mysql
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Step 6 — Run Against Specific Group

Only deploy to web:

ansible-playbook -i inventory.ini multi-server.yml --limit web
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This teaches targeting.

Step 7 — Add Group Variables (Important)

Create folder:

mkdir group_vars
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Create:

vim group_vars/web.yml
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package_name: nginx
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Create:

vim group_vars/db.yml
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package_name: mysql-server
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Now modify playbook:

- name: Install package
  apt:
    name: "{{ package_name }}"
    state: present
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Group → Variable → Behavior change

This is real DevOps practice.

Real Industry Connection

In production:

[web] → Auto Scaling Group
[db] → RDS or DB cluster
[monitoring] → Prometheus servers
[workers] → Background processors

Ansible handles configuration layer.

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