Steps to Set Up Ansible on AWS EC2 Instances

Ansible Setup on AWS

Step 1: Launch Instances

Launch Amazon Linux instances on AWS:

• Control Node: The server to install Ansible.
• Managed Nodes: Servers managed by Ansible.

Step 2: Install Ansible on the Control Node

Update the system:

sudo yum update -y

Install EPEL Repository:

sudo amazon-linux-extras install epel -y

Install Ansible:

sudo yum install ansible -y

Step 3: Create a User on All Servers

Create a user, for example, ansibleuser:

sudo useradd ansibleuser
sudo passwd ansibleuser

Step 4: Grant Sudo Permission to the User

Edit the sudoers file:

sudo visudo

Add this line:

ansibleuser ALL=(ALL) NOPASSWD: ALL

Step 5: Setup Passwordless Authentication on All Servers

Edit SSH configuration:

sudo vim /etc/ssh/sshd_config

Set PasswordAuthentication to yes and restart SSH:

sudo service sshd restart

Generate SSH Key on Control Node:

ssh-keygen -t rsa

Copy the SSH Key to Managed Nodes:

ssh-copy-id ansibleuser@<managed_node_ip>

Step 6: Uncomment Hosts Entry in Ansible Configuration

Edit the Ansible config file:

sudo vim /etc/ansible/ansible.cfg

Uncomment the line:

inventory = /etc/ansible/hosts

Step 7: Configure the Hosts File

Edit the hosts file and add Managed Nodes:

[web-server]
managed_node1_pvt_ip
managed_node2_pvt_ip

[db-server]
managed_node3_pvt_ip
managed_node4_pvt_ip

Step 8: Run Ad-hoc Commands

Test connectivity with:

ansible all -m ping

Step 9: Common Ad-hoc Commands

List all hosts:

ansible all --list-hosts

Ping all hosts:

ansible all -m ping

Note:

To avoid receiving a warning, add the line interpreter_python=auto_silent to the file /etc/ansible/ansible.cfg at any location.

Run the uptime command:

ansible all -m command -a "uptime"

Step 10: Ansible Playbook

A Playbook is a YAML configuration file that defines tasks for remote servers. Run a Playbook with:

ansible-playbook <playbook_name>.yaml

Step 11: Ansible Playbook Commands

Check for syntax errors:

ansible-playbook <playbook_name>.yaml --syntax-check

Perform a dry run:

ansible-playbook <playbook_name>.yaml --check