What is Kernel?

The kernel is the central part of an operating system that manages system resources and provides essential services to the higher-level software running on the computer. It acts as a bridge between the hardware and the software.

The main functions of a kernel include:

1. Memory management

2. Process management

3. Device management

4. File system management

5. Inter-process communication (IPC)

What is Shell?

A shell is a command-line interface (CLI) or a text-based user interface that allows users to interact with the operating system by entering text commands. It is a program that interprets and executes commands entered by the user and acts as an intermediary between the user and the operating system.

What is Linux Shell Scripting?

Linux shell scripting refers to the process of writing and executing scripts in a shell environment on a Linux-based operating system. A shell script is a series of commands written in a scripting language that is interpreted by the shell (like Bash, Zsh, or others) to perform various tasks or automate processes on a Linux system. The most commonly used shell for Linux scripting is Bash (Bourne Again SHell), which comes pre-installed on most Linux distributions.

Shell Scripting for DevOps

Shell scripting is a fundamental skill for DevOps professionals as it enables automation, configuration management, and orchestration of various tasks and processes in the development and operations workflows. Here are some key areas where shell scripting plays a crucial role in DevOps:

Automation: DevOps heavily relies on automation to streamline repetitive tasks and reduce human error.

Infrastructure Provisioning: Infrastructure as Code (IaC) is a core concept in DevOps. Shell scripts can be used to provision and configure virtual machines, containers, and cloud resources.

Monitoring and Logging: Shell scripts can be used to monitor system resources, check log files for errors, and generate reports on system performance.

Data Backup and Restoration: Shell scripts can automate the process of backing up critical data and restoring it when needed, ensuring data integrity and availability.

What is #!/bin/bash? can we write #!/bin/sh as well?

#!/bin/bash is called a "shebang" or "hashbang" line It is the first line in a shell script and tells the system that tells the path of the interpreter basically we are telling open this interpreter (#!/bin/bash) and execute all the commands that we write in the interpreter. Similarly, you can use #!/bin/sh in the shebang line to specify that the script should be executed using the system's default POSIX-compliant shell.

Write a Shell Script that prints I will complete #90DaysOofDevOps challenge

Write a Shell Script to take user input, input from arguments and print the variables.

Write an Example of If else in Shell Scripting by comparing 2 numbers

Let's take an example:

Here is the result

Thank you for reading!