The Role of Shell Scripting for DevOps in Modern Automation

In modern DevOps environments, automation is the backbone of continuous integration and continuous delivery (CI/CD). Shell Scripting for DevOps plays a vital role in achieving this automation by bridging the gap between developers, operations teams, and infrastructure tools.

Whether you’re managing servers, deploying applications, or monitoring resources, shell scripts help automate repetitive tasks — saving time, reducing human error, and improving reliability.

What is Shell Scripting?

A shell script is a sequence of commands written for a Unix-based shell (like Bash, Zsh, or Ksh). These scripts automate command-line operations, system configurations, and deployments.

In DevOps, shell scripting is commonly used to manage CI/CD pipelines, monitor system performance, and execute tasks such as backups, service restarts, and log management.

Why Shell Scripting Matters in DevOps?

Here’s why every DevOps engineer should know shell scripting:

• Automation: Reduces manual intervention for routine server or application tasks.
• Integration: Works seamlessly with Jenkins, Ansible, Docker, and Kubernetes.
• Speed: Executes native OS commands quickly.
• Consistency: Ensures predictable, repeatable outcomes.
• Scalability: Useful for provisioning and managing multiple servers.

Common Use Cases of Shell Scripting in DevOps

#!/bin/bash
set -e

echo "🚀 Starting CI/CD Deployment..."

# Pull latest code
git pull origin main

# Build Docker image
docker build -t myapp:latest .

# Stop old container (if running)
docker stop myapp || true
docker rm myapp || true

# Run new container
docker run -d -p 8080:80 --name myapp myapp:latest

echo "✅ Deployment completed successfully!"

#!/bin/bash
CPU_USAGE=$(top -bn1 | grep "Cpu(s)" | awk '{print $2 + $4}')
MEM_USAGE=$(free -m | awk '/Mem:/ {print $3/\ * 100.0}')

if (( $(echo "$CPU_USAGE > 80.0" | bc -l) )); then
  echo "⚠️ High CPU usage: ${CPU_USAGE}%"
fi

if (( $(echo "$MEM_USAGE > 85.0" | bc -l) )); then
  echo "⚠️ High Memory usage: ${MEM_USAGE}%"
fi

import subprocess

# Execute a shell command
result = subprocess.run(["bash", "deploy.sh"], capture_output=True, text=True)

if result.returncode == 0:
    print("✅ Deployment successful.")
else:
    print("❌ Deployment failed:", result.stderr)