Lesson 3: Shell Scripting for DevOps

What is Shell Scripting?

Shell scripting is the practice of writing scripts using a shell (commonly Bash) to automate tasks, manage systems, and streamline DevOps workflows.

Why Shell Scripting is Important for DevOps

• Automates repetitive administrative tasks
• Improves system consistency and reliability
• Forms the backbone of CI/CD pipelines
• Essential for server provisioning and monitoring

Bash Script Basics

• Shebang: #!/bin/bash
• Script execution permissions
• Running scripts using ./script.sh or bash script.sh

Variables and User Input

• Defining variables: name="DevOps"
• Accessing variables using $name
• Reading user input with read

Conditional Statements

• if, else, elif conditions
• File and string comparisons
• Exit status based decisions

Loops in Shell Scripting

• for loops
• while loops
• Automating repetitive operations

Shell Scripting in Real DevOps Scenarios

• Log rotation and cleanup
• Health check automation
• Backup and restore scripts
• Service restart and monitoring