175 lines
8.8 KiB
Markdown
175 lines
8.8 KiB
Markdown
# Introduction
|
|
|
|
## Prerequisites
|
|
|
|
- Experience of working on any operating systems like Windows, Linux or Mac
|
|
- Basics of operating system
|
|
|
|
## What to expect from this course
|
|
|
|
This course is divided into three parts. In the first part, we will cover the
|
|
fundamentals of linux operating systems. We will talk about linux architecture,
|
|
linux distributions and uses of linux operating systems. We will also talk about
|
|
difference between GUI and CLI.
|
|
|
|
In the second part, we will study about some of the basic commands that are used
|
|
in linux. We will focus on commands used for navigating file system, commands used
|
|
for manipulating files, commands used for viewing files, I/O redirection etc.
|
|
|
|
In the third part, we will study about linux system administration. In this part, we
|
|
will focus on day to day tasks performed by linux admins like managing users/groups,
|
|
managing file permissions, monitoring system performance, log files etc.
|
|
|
|
In the second and third part, we will be taking examples to understand the concepts.
|
|
|
|
## What is not covered under this course
|
|
|
|
We are not covering advanced linux commands and bash scripting in this
|
|
course. We will also not be covering linux internals.
|
|
|
|
## Course Content
|
|
|
|
The following topics has been covered in this course:
|
|
|
|
- [Introduction to Linux](https://linkedin.github.io/school-of-sre/linux_basics/intro/)
|
|
- [What are Linux Operating Systems](https://linkedin.github.io/school-of-sre/linux_basics/intro/#what-are-linux-operating-systems)
|
|
- [What are popular Linux distributions](https://linkedin.github.io/school-of-sre/linux_basics/intro/#what-are-popular-linux-distributions)
|
|
- [Uses of Linux Operating Systems](https://linkedin.github.io/school-of-sre/linux_basics/intro/#uses-of-linux-operating-systems)
|
|
- [Linux Architecture](https://linkedin.github.io/school-of-sre/linux_basics/intro/#linux-architecture)
|
|
- [Graphical user interface (GUI) vs Command line interface (CLI)](https://linkedin.github.io/school-of-sre/linux_basics/intro/#graphical-user-interface-gui-vs-command-line-interface-cli)
|
|
- [Command Line Basics](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/)
|
|
- [Lab Environment Setup](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/lab-environment-setup)
|
|
- [What is a Command](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#what-is-a-command)
|
|
- [File System Organization](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#file-system-organization)
|
|
- [Navigating File System](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#commands-for-navigating-the-file-system)
|
|
- [Manipulating Files](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#commands-for-manipulating-files)
|
|
- [Viewing Files](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#commands-for-viewing-files)
|
|
- [Echo Command](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#echo-command)
|
|
- [Text Processing Commands](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#text-processing-commands)
|
|
- [I/O Redirection](https://linkedin.github.io/school-of-sre/linux_basics/command_line_basics/#io-redirection)
|
|
- [Linux system administration](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/)
|
|
- [Lab Environment Setup](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/lab-environment-setup)
|
|
- [User/Groups management](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#usergroup-management)
|
|
- [Becoming a Superuser](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#becoming-a-superuser)
|
|
- [File Permissions](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#file-permissions)
|
|
- [SSH Command](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#ssh-command)
|
|
- [Package Management](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#package-management)
|
|
- [Process Management](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#process-management)
|
|
- [Memory Management](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#memory-management)
|
|
- [Daemons and Systemd](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#daemons)
|
|
- [Logs](https://linkedin.github.io/school-of-sre/linux_basics/linux_server_administration/#logs)
|
|
- [Conclusion](https://linkedin.github.io/school-of-sre/linux_basics/conclusion)
|
|
- [Applications in SRE Role](https://linkedin.github.io/school-of-sre/linux_basics/conclusion/#applications-in-sre-role)
|
|
- [Useful Courses and tutorials](https://linkedin.github.io/school-of-sre/linux_basics/conclusion/#useful-courses-and-tutorials)
|
|
|
|
## What are Linux operating systems
|
|
|
|
Most of us will be familiar with the windows operating system which is
|
|
used in more than 75% of the personal computers. The windows operating systems
|
|
are based on windows NT kernel. A kernel is the most important part of
|
|
an operating system which performs important functions like process
|
|
management, memory management, filesystem management etc.
|
|
|
|
Linux operating systems are based on the Linux kernel. A linux based
|
|
operating system will consist of linux kernel, GUI/CLI, system libraries
|
|
and system utilities. The Linux kernel was independently developed and
|
|
released by Linus Torvalds. The linux kernel is free and open-source -
|
|
[https://github.com/torvalds/linux](https://github.com/torvalds/linux)
|
|
|
|
History of Linux -
|
|
[https://en.wikipedia.org/wiki/History_of_Linux](https://en.wikipedia.org/wiki/History_of_Linux)
|
|
|
|
## What are popular Linux distributions
|
|
|
|
A linux distribution(distro) is an operating system that is based on
|
|
the linux kernel and a package management system. A package management
|
|
system consists of tools that helps in installing, upgrading,
|
|
configuring and removing softwares on the operating system.
|
|
|
|
Softwares are usually adopted to a distribution and are packaged in a
|
|
distro specific format. These packages are available through a distro
|
|
specific repository. Packages are installed and managed in the operating
|
|
system by a package manager.
|
|
|
|
**List of popular Linux distributions:**
|
|
|
|
- Fedora
|
|
|
|
- Ubuntu
|
|
|
|
- Debian
|
|
|
|
- Centos
|
|
|
|
- Red Hat Enterprise Linux
|
|
|
|
- Suse
|
|
|
|
- Arch Linux
|
|
|
|
|
|
| Packaging systems | Distributions | Package manager
|
|
| ---------------------- | ------------------------------------------ | -----------------
|
|
| Debian style (.deb) | Debian, Ubuntu | APT
|
|
| Red Hat style (.rpm) | Fedora, CentOS, Red Hat Enterprise Linux | YUM
|
|
|
|
## Linux Architecture
|
|
|
|
|
|
|
|
- The Linux kernel is monolithic in nature.
|
|
|
|
- System calls are used to interact with the linux kernel space.
|
|
|
|
- Kernel code can only be executed in the kernel mode. Non-kernel code is executed in the user mode.
|
|
|
|
- Device drivers are used to communicate with the hardware devices.
|
|
|
|
## Uses of Linux Operating Systems
|
|
|
|
Operating system based on linux kernel are widely used in:
|
|
|
|
- Personal computers
|
|
|
|
- Servers
|
|
|
|
- Mobile phones - Android is based on linux operating system
|
|
|
|
- Embedded devices - watches, televisions, traffic lights etc
|
|
|
|
- Satelites
|
|
|
|
- Network devices - routers, switches etc.
|
|
|
|
## Graphical user interface (GUI) vs Command line interface (CLI)
|
|
|
|
A user interacts with a computer with the help of user interfaces. The
|
|
user interface can be either GUI or CLI.
|
|
|
|
Graphical user interface allows a user to interact with the computer
|
|
using graphics such as icons and images. When a user clicks on an icon
|
|
to open an application on a computer, he or she is actually using the
|
|
GUI. It's easy to perform tasks using GUI.
|
|
|
|
Command line interface allows a user to interact with the computer using
|
|
commands. A user types the command in a terminal and the system helps in
|
|
executing these commands. A new user with experience on GUI may find it
|
|
difficult to interact with CLI as he/she needs to be aware of the commands
|
|
to perform a particular operation.
|
|
|
|
## Shell vs Terminal
|
|
|
|
Shell is a program that takes command or a group of commands from the
|
|
users and gives them to the operating system for processing. Shell is an
|
|
example of command line interface. Bash is one of the most popular shell
|
|
programs available on linux servers. Other popular shell programs are
|
|
zsh, ksh and tcsh.
|
|
|
|
Terminal is a program that opens a window and lets you interact with the
|
|
shell. Some popular examples of terminals are gnome-terminal, xterm,
|
|
konsole etc.
|
|
|
|
Linux users do use the terms shell, terminal, prompt, console etc.
|
|
interchangeably. In simple terms, these all refer to a way of taking
|
|
commands from the user.
|