Introduction to linux

1. Linux System
Adminstration
Introduction

2. Course Objectives
1. Course Description
This course provides the necessary knowledge and skills permitting to perform the
basic operations related to the administration of Linux operating system. This course
covers how to administer, configure and upgrade Linux systems. It also covers how to
use state-of-the art system administration techniques in real-life scenarios via
practical labs.
2. Course Main Objective
• Understanding the main components of Linux architecture.
• Develop skills of configuring Linux
• Develop skills of writing Linux scripts.
• Develop skills of setting up user accounts and implementing authentication
policies.
• Develop skills of performing important OS operations (backup, restore, audit).

3. Assessment Strategy
Assessment through the course will be via:
1. Lecture quizzes.
2. Assignments (Sheets , Reports or Lab. Activities).
3. Mid-Term Exams.
4. Final Exam.

4. Assessment Strategy
# Assessment task Week Due Percentage of Total Assessment Sore
1 First Exam Week 5 20
2 Second Exam Week 10 20
3 Final Exam Week 13 40
4 Lab. Exam/ Lab
report
Every week 10 %
5 Participation and
discussion
Every week 5%
6 Group/individual
project
1/semester 5%

5. Course Content
No List of Topics
1 Installing Linux operating system
2
User account management: access settings, password policies,
Documentation methods, group policies
3 Command line interfaces
4 Configuration management
5 Updates and corrections
6 Records and audit of events
7 System services management
8 Virtual environments
9 Prepare backups and restore data
10 File System Security
11 Network Settings
12 Host-based intrusion detection systems (HIDS)
13 developing security policies

6. LECTURE 1
INTRODUCTION TO LINUX

7. Agenda
01
The Linux
Operating
system
03
The History of
Linux
05
Computer
Organization
02
Licensing
Linux
04
What is an
Operating
System?

8. What is an Operating System?
A program that acts as an intermediary between a
user of a computer and the computer hardware.
Operating system goals:
 Execute user programs and make solving user problems
easier.
 Make the computer system convenient to use.
Use the computer hardware in an efficient manner.
Operating systems are an essential part of any
computer system and any computer science
education.

9. Computer Organization
1
2
consists of the physical
components inside a computer.
Hardware
Every computer has two fundamental types
of components:
The sets of instructions or
programs that allow the hardware
components to manipulate data
(or files).
Software

10. Physical memory (RAM)
stores information needed by the processor.
Processor
(the central processing unit
or CPU), which computes
information.
Storage
 Hard disk and solid-state disk drives.
 CD/DVD drives.
 Flash memory card readers.
I/O Devices
Hardware

11. These programs are loaded into parts of
your computer hardware (RAM and CPU) .
A program is a file stored on your
computer.
A process is that file in execution.

12. B
A
Applications
• such as word such as
word such as word
processors, computer
games and graphical
manipulation
Operating
system(OS) consists of
a set of software
components that control
the hardware of your
computer.
Types of programs

13. OS user and System view
To understand more fully the operating
system’s role, we next explore operating
systems from two viewpoints:
The user view
The system view.

14. OS user view
The user’s view of the computer varies according to the
interface being used:
Ease of use, with some
attention paid to
performance and none paid
to resource utilization
maximize resource
utilization— to assure
that all available CPU
time, memory, and I/O
are used efficiently and.
compromise between
individual usability and
resource utilization.

15. OS System view
 From the computer’s point of view, the operating system is
the program most intimately involved with the hardware. In
this context, we can view an operating system as a resource
allocator.
 A slightly different view of an operating system emphasizes
the need to control the various I/O devices and user
programs.
 An operating system is a control program. A control
program manages the execution of user programs to
prevent errors and improper use of the computer. It is
especially concerned with the operation and control of
I/O devices.

16. Operating System Definition
OS is a resource allocator
Manages all resources.
Decides between conflicting requests for
efficient and fair resource use.
OS is a control program
Controls execution of programs to prevent
errors and improper use of the computer
“The one program running at all times on the computer” is the
kernel. Everything else is either a system program (ships with the
operating system) or an application program

17. Operating System Definition (cont.)
The operating system is the one program running
at all times on the computer—usually called the
kernel.
Along with the kernel, there are two other types
of programs:
 system programs, which are associated with the
operating system but are not necessarily part of the
kernel.
 Application programs, which include all programs not
associated with the operation of the system.)

18. Operating System Activities
Different OS functions are:
Process Management.
Memory Management.
File Management.
Storage Management.
I/O Management.
Protection Management.
Networking Management.

19. The Linux Operating System

20. The Linux Operating System
• An operating system you use to run applications on a variety of
hardware.
• From within the interface, you can execute commands that tell the
operating system and other applications to perform specific tasks.
• The operating system then uses the computer hardware to
perform the tasks required by the applications.
• Linux can manage thousands of tasks at the same time, including
allowing
• Multiple users to access the system simultaneously.
• Hence, Linux is referred to as a multiuser and multitasking
operating system.

21. Linux is open source.
Linux is released under the GNU
General Public License (GPL).
Linux has a better community support.
Linux is secure and
virus free.
 Linux is growing in the home users sector and the
dominant of the professional and servers sector.
 Internet service providers (ISPs), e-commerce
sites, and other commercial applications all use
Linux today and continue to increase their
commitment to Linux.
The Linux Operating System

22. • The core component of the Linux operating system is
called the Linux kernel.
• The Linux kernel and supporting software (called
function libraries) are written almost entirely in the C
programming language
• You might sometimes need to upgrade the kernel after
installing Linux to take advantage of new technologies
or to fix problems (also known as bugs) related to your
computer’s hardware.
Versions of The Linux Operating System

23. Types of Linux
kernel
not fully tested and imply instability
Developmental kernels
Tested by several Linux developers and are declared
stable.
Production kernels

24. Linux kernel versions are made up of the following three
components:
• Major number
• Minor number
• Revision number
4 . 17 . 6
The major version of the Linux
kernel.
 The minor revision of the Linux kernel.
 As new features are added to the Linux kernel over
time, the minor number is incremented.
Revision number indicating the most current
changes to the version of the particular
kernel that is being released

25. Most developmental kernels append the minor number with the
letters -rc (release candidate) followed by a number that
represents the version of the developmental kernel
Developmental kernel is the third release candidate for the 4.18 kernel
4 . 18 . -rc3
When choosing a kernel for a mission-critical computer such as a
server, ensure that you choose a production kernel. This reduces
the chance that you will encounter a bug in the kernel, which
saves you the time needed to change kernels.

26. Licensing Linux

27. Open Source Closed Source Freeware Shareware

28.  Linux adheres to the GNU General Public License (GPL), which was
developed by the Free Software Foundation (FSF).
 The GPL stated that the source code of any software published under
its license must be freely available. If someone modifies that source
code, that person must also redistribute that source code freely,
thereby keeping the source code free forever.
 Another type of open source license is the artistic license, which
ensures that the source code of the program is freely available yet
allows the original author of the source code some control over the
changes made to it.

29.  Closed source software can be distributed for free or for a cost;
either way, the source code for the software is unavailable from the
original developers. The majority of closed source software is sold
commercially and bears the label of its manufacturer.
 Another type of closed source software is freeware, in which the
software program is distributed free of charge, yet the source code is
unavailable. Freeware might also contain licenses that restrict the
distribution of source code.
 Another approach to this style of closed source licensing is
shareware, which is distributed free of charge, yet after a certain
number of hours of usage or to gain certain features of the program,
payment is required.

30. 1
Linux is freely developed and continuously improved
by a large community of software developers.
2
For this reason, it is referred to as Open Source
Software (OSS).
3
Source code refers to the list of instructions that a
software developer writes to make up a program.

31. 1- Risk reduction: Collaborative open-source development
results in constant software improvement.
2- Meeting business needs: Linux provides support for most
programming languages.
3- Stability: collaboration among several developers with a
common need are created quickly.
4- Security: Linux source code is freely available and publicly
inspected,
5- Ease of customization: Only software packages necessary
to perform certain tasks need to be installed.
6- Cost reduction: Linux is less expensive than other operating
systems

32. The History of Linux

33. Multics was developed in the 1963-1969 period through
the collaboration of the Massachusetts Institute of
Technology (MIT), General Electric, and Bell Labs.
 Unix first version created in Bell Labs in 1969.
Unix flavors:
IBM->AIX
Hewlett-Packard->HP/UX
Sun-> Solaris
Silicon Graphics->IRIX
Operate in a same manner.
Offer the same standard utilities and commands.

34. In 1983, Richard Stallman started the GNU project
with the goal of creating a free UNIX-like operating
system.
GNU General Public License (GPL).
Free Software Foundation (FSF).
 In 1991, Linus Torvalds created Linux kernel.
 In 1992, Linux and GNU developers worked to
integrate GNU components with Linux to make a fully
functional and free operating system.

35. A distribution of Linux containing:
The Linux kernel.
 Common function libraries.
A series of OSS packages.
Some Linux distributions include:
Many server-related tools.
Numerous workstation and development software
applications.
A complete set of open source tools that you can use
to customize a Linux system to perform specific
functions.

38. Kernel
Shell
Terminal
• The core of the OS.
• Contains components like device drivers.
• It loads into RAM when the machine boots
and stays
• Provides an interface by which the user can
communicate with the kernel.
• “bash” is the most commonly used shell on
Linux.
Gives the shell a place to accept typed
commands and to display their results.

39. Cloud
systems
Internet
servers
Super-
computers
Scientific
and personal
workstations
Mobile
devices
1
2
4
5
3
6
Cybersecurity
workstations

40. THANKS!
Best Regards!