Hello, DevOps enthusiasts! 👋
On Day 04 of my #90DaysOfDevOps journey, I explored Basic Linux Shell Scripting and its importance in the life of a DevOps engineer. Shell scripting is an essential tool for automating processes, and this session introduced me to writing scripts for various tasks. Let’s dive into what I learned and accomplished today!
🛠️ Tasks and Solutions
Task 1: What is Shell Scripting?
Shell scripting involves writing a series of commands in a script file to automate tasks in a Unix/Linux environment.
Why is it important for DevOps?
Automates repetitive tasks.
Simplifies system management and configurations.
Speeds up CI/CD pipelines.
Reduces manual errors, saving time and effort.
Example: A script to check the disk usage of a system:
#!/bin/bash
df -h > disk_usage_report.txt
echo "Disk usage report saved to disk_usage_report.txt"
Task 2: What is #!/bin/bash? Can we write #!/bin/sh as well?
The shebang line (#!) indicates the interpreter to execute the script.
#!/bin/bash: Uses Bash, which supports advanced features like arrays and functions.#!/bin/sh: Uses the Bourne shell, more compatible with POSIX-compliant systems.
Example Difference:
#!/bin/bash
echo ${BASH_VERSION} # Only works in Bash
#!/bin/sh
echo "POSIX-compliant script"
Task 3: Write a Shell Script to Print a Message
Script:
#!/bin/bash
<<about
Author : Amitabh Soni
Date : 23/11/24
Description : This shell script will print I will complete #90DaysOfDevOps challenge
about
echo "I will complete #90DaysOfDevOps challenge"
Execution Output:
Task 4: Script to Take User Input and Arguments
Script:
#!/bin/bash
<<Info
Author : Amitabh soni
Date : 23/11/24
Description : This scripts takes input from user and print it
Info
# userName
read -p "Enter your name : " name
# storing arguments
arg1=$1
arg2=$2
# Printing name and passed arguments
echo "Your name is ${name} and arguments passed : ${arg1} , ${arg2}."
Execution:
Task 5: If-Else Statement Comparing Two Numbers
Script:
#!/bin/bash
<<info
Author : Amitabh soni
Date : 23/11/24
Description : This script will compare two numbers using If-else statements
info
# user input
read -p "Enter number 1 : " n1
read -p "Enter number 2 : " n2
# Actual program
if [[ $n1 -gt $n2 ]]; then
echo "$n1 is greater than $n2"
elif [[ $n1 -lt $n2 ]];then
echo "$n2 is greater than $n1"
else
echo "$n1 is equal to $n2"
fi
Execution Output:
🎉 Takeaway
Today’s tasks gave me a solid foundation in Linux shell scripting, which is crucial for automating and optimizing processes in DevOps workflows. I’m excited to keep building on this knowledge in the upcoming days.
You can find my solutions and scripts here: GitHub Repository
Let me know your thoughts and feedback in the comments below! 🚀
#DevOps #Linux #ShellScripting #Automation #LearningJourney