Chapter 1 : Introduction to Linux

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Basics of Operating System


  • OS manages computer hardware and also acts as intermediary between user and hardware.
  • Computer hardware consists of CPU, Memory and I/O Devices. 
  • Main functions of OS are 
    • Allocation of resources
    • Load and manage processes
    • Provide interface to hardware via system call
    • Basic UI, 
    • Provide file system 
    • Management of memory and security etc.
  • Types of OS are
    • Single and Multi tasking
    • Single and Multi User
    • Distributed
    • Templated (Eg., Virtual Image)
  • Various OS available in the market are
    • Windows
    • MacOS
    • Unix/Linux based.

What is Linux

  • Above picture shows main components in Linux OS such as Kernel, Sys Libs, System default softwares, User process and utility, Kernel modules etc.
  • The main features of Linux are:
    • Detecting and preparing hardware 
    • Managing processes 
    • Managing memory 
    • Providing user interfaces
    • Controlling filesystems
    • Providing user access and authentication
  • Advanced features in Linux, often used in large enterprises, include the following:
    • Clustering 
    • Virtualization 
  • Linux is Opensource. Its source code is available online and it can be used to make changes to the source code and also understand the vulnerabilities and fix them.

Linux Distributions

  • Linux Distributions is combination of Linux Kernal and collection of Linux Apps. 
  • Two popular distros are Redhat and Ubuntu.
  • CentOS is the freeware of Redhat. Redhat is mainly used in large based companies and Ubuntu is used in smaller software solutions.

Installation of Linux

  • Below are the links which explains the installtion of Linux on virtual box or on hard drive. Please check.

Basic Duties of System Administrator

  • Account provisioning
  • Adding and removing hardware
  • Performing backups
  • Installing and upgrading software
  • Monitoring the system
  • Troubleshooting
  • Maintaining local documentation
  • Vigilantly monitoring security



References :
1. Linux Bible(by Christopher Negus)
2. Unix and Linux System Administration Handbook(by Evi Nemeth, Garth Snyder, Trent R. Hein,)
3. https://en.wikipedia.org/wiki/Operating_system

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