Welcome back to my #DevOpsJourney! In Day 3-4, we’re diving into one of the most powerful tools in any DevOps toolkit: Shell Scripting. Automating routine tasks, and streamlining processes—these are just a few of the things we can achieve with shell scripts.

Let's break down the basics and see how you can unlock the power of automation in your workflows.

Think of shell scripting like a recipe book 📚. By writing the right instructions, you can automate time-consuming tasks and bring efficiency to your operations.

🖥️ 1. Getting Started with Shell Scripting

A shell script is just a file with a sequence of terminal commands. When run, the shell executes them in order.

Create Your First Script:

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Add this line at the top to specify the shell:

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Add your first command:

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Make it executable:

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Run it:

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Boom! You've just created your first working script 🎉

⚙️ 2. Control Flow & Logic in Shell Scripting

Shell scripts become powerful when you add logic like conditionals and loops.

If-Else Condition:

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For Loop:

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While Loop:

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📜 3. Advanced Techniques

Once We’ve nailed the basics, start using variables, functions, redirections, and scheduling.

Variables:

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Functions:

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Redirecting Output:

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Redirecting Errors:

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Cron Job for Scheduling:

Edit crontab:

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Example to run a script daily at midnight:

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🔧 4. Handy Shell Commands

Some useful commands often used in automation:

*grep * – Search patterns in files

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*sed *– Find and replace in files

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*awk *– Process text and data

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tar – Create backups

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📈 5. Real-World Use Cases in DevOps

✅ Automated Deployments – Script your deployments for consistency
✅ System Monitoring – Check disk usage, CPU, memory, etc.
✅ Backup Automation – Schedule daily or weekly backups
✅ Log Management – Analyze and filter logs programmatically

🏁 Wrapping Up

Shell scripting is a must-have skill for anyone diving into DevOps.
It brings automation, speed, and precision to your daily tasks and long-term projects.

Start simple. Automate small tasks. Then scale your knowledge to tackle bigger challenges.

What’s one script you’ve written that saved you tons of time?
Let’s connect and share ideas! 💬