SRJahirTech

DevOps Roadmap — Part 5: Shell Scripting for DevOps

DevOps ka real kaam yahan se start hota hai.

Jo kaam tum manually 10 baar kar rahe ho, DevOps usko script likh ke 1 baar karta hai.

What Is Shell Scripting?

Shell scripting means:

• Linux commands ko ek file me likhna
• Repeatable automation banana
• Human error kam karna

DevOps engineer ka sabse pehla automation tool = Bash

Your First Shell Script

nano hello.sh

#!/bin/bash
echo "Hello DevOps World"

chmod +x hello.sh
./hello.sh

#!/bin/bash batata hai kaunsa shell use hoga.

Variables — Store Information

#!/bin/bash
NAME="Suraj"
echo "Hello $NAME"

Variables help DevOps scripts become flexible.

Taking User Input

#!/bin/bash
echo "Enter your name:"
read USER
echo "Welcome $USER"

Scripts can interact with humans or systems.

Conditions — Decision Making

#!/bin/bash
if [ -f "/etc/passwd" ]; then
  echo "File exists"
else
  echo "File missing"
fi

Production scripts are full of conditions.

Loops — Automation Power

#!/bin/bash
for i in 1 2 3 4 5
do
  echo "Deployment step $i"
done

Imagine deploying 50 servers without loops — impossible.

Real DevOps Script Example

Check disk usage and alert.

#!/bin/bash
USAGE=$(df / | tail -1 | awk '{print $5}' | sed 's/%//')

if [ $USAGE -gt 80 ]; then
  echo "Warning: Disk usage above 80%"
else
  echo "Disk usage normal"
fi

This is real-world DevOps thinking.

Why Shell Scripting Is Mandatory

• CI/CD pipelines use shell
• Server automation uses shell
• Cloud init scripts use shell

Without shell scripting, DevOps engineer incomplete hai.

Practice Daily (Very Important)

• Write 1 script daily
• Automate boring tasks
• Break scripts and fix them

Next Step in DevOps Roadmap

Now we need team collaboration. That means Git & Version Control.