Task Information
The Nautilus Application development team wanted to test some applications on app servers in Stratos Datacenter. They shared some pre-requisites with the DevOps team, and packages need to be installed on app servers. Since we are already using Ansible for automating such tasks, please perform this task using Ansible as per details mentioned below:
Create an inventory file /home/thor/playbook/inventory on jump host and add all app servers in it.
Create an Ansible playbook /home/thor/playbook/playbook.yml to install wget package on all app servers using Ansible yum module.
Make sure user thor should be able to run the playbook on jump host.
Task Solutions
✅ Part 1: Lab Step-by-Step Guidelines (Technical & Precise)
Step 1: Generate SSH Key on Jump Host (as thor)
ssh-keygen
Step 2: Copy Public Key to Each App Server
Run:
ssh-copy-id tony@172.16.238.10
ssh-copy-id steve@172.16.238.11
ssh-copy-id banner@172.16.238.12
Enter respective passwords when prompted:
Ir0nM@n
Am3ric@
BigGr33n
Step 3: Create Playbook Directory
mkdir -p /home/thor/playbook
Step 4: Create Inventory File
Create inventory file:
vi /home/thor/playbook/inventory
Add all app servers under a group (example format below):
[app_servers]
stapp01 ansible_host=172.16.238.10 ansible_user=tony ansible_become=yes
stapp02 ansible_host=172.16.238.11 ansible_user=steve ansible_become=yes
stapp03 ansible_host=172.16.238.12 ansible_user=banner ansible_become=yes
Save and exit.
Step 5: Create Ansible Playbook
vi /home/thor/playbook/playbook.yml
Add the following YAML configuration:
---
- name: Install wget on app servers
hosts: app_servers
become: yes
tasks:
- name: Install wget package
yum:
name: wget
state: present
Save and exit.
Step 6: Verify Permissions for thor
Ensure thor owns the files:
ls -l /home/thor/playbook
If needed:
chown -R thor:thor /home/thor/playbook
Step 7: Run the Playbook as thor
ansible-playbook -i /home/thor/playbook/inventory /home/thor/playbook/playbook.yml
Step 8: Verify Installation on App Servers
You can verify using:
ansible app_servers -i /home/thor/playbook/inventory -a "rpm -q wget"
Expected output:
stapp03 | CHANGED | rc=0 >>
wget-1.21.1-8.el9.x86_64
stapp02 | CHANGED | rc=0 >>
wget-1.21.1-8.el9.x86_64
stapp01 | CHANGED | rc=0 >>
wget-1.21.1-8.el9.x86_64
🧠 Part 2: Simple Step-by-Step Explanation (Beginner Friendly)
🔐 Step 1: Generate SSH Key
ssh-keygen
What this does:
This creates a secure digital key pair:
A private key (kept on the jump server)
A public key (copied to other servers)
Think of it like:
🔑 Private key = your secret house key
🔓 Public key = a lock installed on each app server
When you try to connect, the server checks:
“Does this key match the lock I have?”
If yes → You’re allowed in without typing a password.
This is more secure and more professional than storing passwords.
📤 Step 2: Copy Public Key to App Servers
ssh-copy-id tony@172.16.238.10
What this does:
It installs your public key onto the app server.
After this:
The jump host (thor) can connect to that server
No password is required anymore
You repeat this for all three app servers.
Now Ansible can log in automatically.
📁 Step 3: Create Playbook Directory
mkdir -p /home/thor/playbook
What this does:
Creates a folder to store:
The server list (inventory)
The automation instructions (playbook)
This keeps everything organized.
📋 Step 4: Create Inventory File
vi /home/thor/playbook/inventory
What is the inventory?
The inventory is:
A contact list of servers Ansible should manage.
Example:
[app_servers]
stapp01 ansible_host=172.16.238.10 ansible_user=tony ansible_become=yes
This tells Ansible:
Connect to IP 172.16.238.10
Login as user tony
Use sudo privileges (become root)
You grouped all three servers under:
[app_servers]
So when Ansible runs, it targets all three at once.
📜 Step 5: Create the Playbook
vi /home/thor/playbook/playbook.yml
What is a playbook?
A playbook is:
A list of instructions telling Ansible what to do.
Your playbook says:
Go to all servers in app_servers
Become root
Install wget
Make sure it is present
The important part:
yum:
name: wget
state: present
This means:
“If wget is not installed → install it.
If it’s already installed → do nothing.”
That makes it safe and repeatable.
🔐 Step 6: Verify File Ownership
ls -l /home/thor/playbook
This ensures:
thor owns the files
thor can execute the playbook
If files belong to another user, Ansible might fail.
▶ Step 7: Run the Playbook
ansible-playbook -i inventory playbook.yml
What happens behind the scenes:
For each server:
Ansible connects using SSH key
Switches to root using sudo
Runs the equivalent of:
sudo yum install wget
Moves to the next server
Reports status
All automatically.
🔎 Step 8: Verify Installation
ansible app_servers -a "rpm -q wget"
This checks:
“Is wget installed?”
Output:
wget-1.21.1-8.el9.x86_64
That means installation was successful.
🎯 What You Just Accomplished
Without logging into each server manually, you:
Connected securely using SSH keys
Installed software on 3 servers at once
Verified installation
Used proper DevOps automation practice
💡 Why This Matters in Real DevOps
Instead of:
Logging into 50 servers one by one
You can:
Run one command
Update all servers instantly
That is the power of Ansible automation.