Linux for DevOps

#Day02

#TrainWithShubham

#90DaysofDevOps

Hashnode ID : - #knowledgesharing https://hashnode.com/@SushantKadam30

Shubham Londhe

Hello Connectors,

Starting with the new learning thrill to share my Day02 studies.

🔍 Introduction to Linux?

• Linux is an operating system which helps to run your computer. Linux was made by Linus Torvalds in September 1991 in C Programming Language.

• Basically, linux is an Open Source that is publicly available unlike Microsoft Windows, and is used by 91% of the Applications on the Internet.

• Linux allows Multi-user and Multi-Tasking with Powerful Shell and Multiple Flavors. (UBUNTU, CENTOS, RHEL, FEDORA, AMAZON LINUX, KALI LINUX, DEBIAN, MINT, PARROT, SUSE....etc).

• Linux allows High Security and doesn't need any Anti-Virus Software.

Everything in Linux is either a File or a Directory.

🔍Why do we learn Linux in DevOps? Why it is Important?

• As a DevOps Engineer, many times you need to give instructions to the comp^. But the instructions are given in Windows to create a "New Folder".

• As in Linux, you are giving commands, whatever you going to do in Linux will be through command.

🔍What does command mean & how to give command?

🔍To whom need to give & what happens after giving a command?

Linux has Architecture

Hardware > Kernel > Shell > Application*.*

Hardware ----- Hard Disk

Kernel ----- (Heart) "It's a code which gives Linux to work on it"

Shell ----- (Terminal) "The command which you give it goes to the kernel and it displays on HW".

Application ----- Notepad, MusicPlayer.

We can't directly talk with KERNEL. I can With the help of the Application I can talk to SHELL & SHELL internally talk to KERNEL and KERNET talk to HW.

🔍 How it works? Let me explain to you.

• Let's say I want to create a folder now the folder that you create will occupy some space on the HDD.

• As I want to create a folder I'll say to "SHELL" to make a directory "mkdir".

• "SHELL" will tell "KERNEL" to create a Folder.

• There's an equivalent code in C programming language that KERNEL executes and it created a folder in Hardware.

& This is how SHELL commands work

Some Linux Basic Commands

#pwd - it shows the present working directory.

#ls - it shows available files and directory list in the present working directory.

#uname - it shows the name of the kernel (os).

#uname -r - it shows the version of the kernel.

#cd - it use for change directory.

#clear - it use for clear screen.

#whoami - it shows currently login user name

#history - it shows list of previously used commands.

#date - it shows time and date.

#touch - it use to create new file.

#mkdir - it use to make directory.