Transcript LN_ch01_02_Unix_Linux_Overview_[2]ch01-02

My Lecture Notes:
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Have a tutorial value: the student should be able to learn from slides,
Comply with research-based principles for design Power Point
presentation
Concepts are presented visually with many diagrams and
pictures.
They use visual aids (diagrams, pictures etc.) and pictures are
presented near each other on the page or screen.
The context is presented in the hierarchical way, details are
indented
Important key words are highlighted or written in different colo
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Credits: Parts of the slides are based on slides created by textbook authors,
Syed M. Sarwar, Robert Koretsky, Syed A. Sarwar
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expanded by Jozef Goetz, 2011
Objectives
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To explain what an operating system is
To describe briefly operating system
services
To describe character and graphical user
interfaces - GUI
To discuss different types of operating
systems
To briefly describe the LINUX operating
system
To describe briefly the history of the
LINUX operating system
To provide an overview of the different
types of LINUX systems
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What is an Operating System?
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Primary purpose is to facilitate:
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Allows users to employ
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Easy, efficient, fair, orderly and secure use of hardware and
software resources.
application software,
language libraries, system calls and
program generation tools.
Two ways of viewing an operating system:
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Top-down – user view
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Bottom up – system view
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E.g., The OS performs the task of dealing with complicated
hardware resources and gives you a comprehensive and simple
machine, ready to use.
In this way the OS provides a virtual machine
E.g., the OS decides how much space how much RAM space is to
be allocated to a program before it is loaded and executed, use
commands such as cp memo myLetters
In this was the OS can be viewed as a resource manager.
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Layered View of a Computer System
App.
User’s
Interface
App.
Programmer's
Interface
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Operating System Services
Communication between processes
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Process control
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Execution of a program
Input and output operations performed by
programs
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Device management
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Manipulation of all types of files
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File management
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Create, terminate processes
Allocate and free memory
Management of users and security
Error detection and reporting
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Character Versus Graphical User Interface.
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Character (Command Line) User Interface
– CUI or CLI
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Input device (e.g., Keyboard is used to issue a
command)
Efficient
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A minimal layer of software is needed between you and
your task on computer
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Character Versus Graphical User Interface.
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Graphical User Interface - GUI
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Input is taken from a point-and-click device.
Most popular desktop environments
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GNU (pronounced /ˈɡnuː/) is a Unix-like computer operating system
developed by the GNU project, ultimately aiming to be a "complete Unixcompatible software system“ composed wholly of free software.
The licenses for most software and other practical works are designed to take away
your freedom to share and change the works.
By contrast, the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free software for
all its users.
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GNU was founded by Richard Stallman
GNU - A set of programs written by the Free Software Foundation to provide
a Free UNIX framework.
GNU is a large component of a Linux distribution.
 Variants of the GNU operating system, which use the kernel called Linux,
are now widely used;
 though these systems are often referred to as “Linux”, they are more
accurately called GNU/Linux systems.
GNU Network Object Model Environment – GNOME
K Desktop Environment - KDE
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Types of Operating Systems
Single-user, single-process system (e.g. DOS)
Single-user, multiprocess system
Multiuser, multiprocess system
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The CPU can be moved from one process to another
process - multiprogramming
multiprocess system increases resource
utilization and system throughput
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Time-sharing systems - Multiuser,
multiprocess and interactive operating
system OS
1.
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The CPU is switched from one process to another giving
the impression of sole use of the system
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The Development of the UNIX Operating System
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Research Operating System
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UNIX Version 1 through UNIX Version 6
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AT& T System V
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Released in 1983
Berkley Software Distributions
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3BSD and 4BSD
The History of Shells
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Developed and Written in C
Releases distributed as C Source Code
The design of the system allowed users to run multiple
processes concurrently and to connect these processes
with streams.
Bourne Shell,
C Shell,
Korn Shell.
Current and Future Developments - UNIX
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Web Resources
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What is Linux?
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Linux is a clone of the operating system
Unix, written from scratch by Linus
Torvalds ’91 with assistance from a
loosely-knit team of hackers across the
Net.
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Table 2.1 Web Resources (continued on next slide)
http://www.linuxbase.org/
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Table 2.1 Web Resources (continued from previous slide)
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Table 2.2 Major LINUX Distributions
Top Ten Distributions as of 11/10/11:
http://distrowatch.com/dwres.php?resource=major
- #1 Ubuntu
The most popular brand of GNU/Linux for newbies is Ubuntu on desktops and notebooks and Android for smart-thingies. Ubuntu
really makes an effort to produce a system easy for newbies.
Once you are comfortable with GNU/Linux in Ubuntu, Ii is recommended Debian GNU/Linux because it gives much more control
over the system. The primary form, Debian GNU/Linux, which uses the Linux kernel and GNU OS tools,is a popular and influential
GNU/Linux distribution
Android is a quite different GUI placed on top of GNU/Linux designed specifically for smart-thingies. One of the the best OS for
smart-thingies because of the huge number of applications you can get for it.
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The 5 most popular Linux distributions
as of 08/26/2012
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From the bottom up we find http://www.zdnet.com/the-5-most-popular-linux-distributions-7000003183/:
5: Debian: I've never been a big Debian fan -- I much prefer Debian-based distributions such as Ubuntu and Mepis -- but lots of other people are.
Debian, which just turned 19, remains important not just because it is the foundation for many other Linux distributions, but because year after
year it continues to be loved by its users.
4: Fedora: But while Debian isn't one of my favorites, I confess I really haven't cared for Fedora, Red Hat's community Linux distribution, in
recent years. Well, it's not so much Fedora, it's the fact that it uses GNOME 3.x -- the desktop interface I love to hate.
Regardless of how I feel about it though, Fedora clearly has its fans. And, if you work on Red Hat Enterprise Linux (RHEL) development, it's a
really wise idea to keep a copy of Fedora on hand so you can see RHEL's future.
3: Ubuntu: What's that you say? Ubuntu: the darling of so many Linux fans only in third place? Yep. It's in third. Why? Well even though I like its
relatively new Unity interface, a lot of other people really don't. I think that mostly it's because while Unity is great for new users who aren't
especially computer savvy, a lot of Linux professionals find it gets in the way -- and, of course, experienced old Linux hands are exactly the kind
of people who visit DistroWatch.
That said, Ubuntu founder Mark Shuttleworth thinks the operating system will see 20 million new PCs sold with Ubuntu in 2012, and that's not
counting people who install it. Those people will also largely be new computer users. If Ubuntu can get most of the new users coming to Linux, I
think they'll be happy even if they're no longer as popular with old-guard Linux desktop users.
2: Mageia: And, number two is, "who?" I can hear some of you asking. Mageia is a September 2010 fork of Mandriva Linux, a commercial
Linux distribution, which was once quite popular in its own right. In 2006, Mandriva suffered management and financial problems. Since then,
while the firm has continued to have problems, Mageia -- freed of Mandrivia's business woes -- has continued on to become a wildly popular
Linux distribution.
And why is Mageia so popular? I think it's because it's a straightforward easy-to-use Linux distribution. Unlike Ubuntu's Unity user interface,
Mageia uses the Linux pro friendly KDE 4.8 desktop. In short, it's just a darn good KDE distribution -- which, by the way -- according to
LinuxQuestions' last survey, is now the single most popular desktop interface of all.
1: Mint Linux: This should come as no surprise. Mint is an excellent distribution and my own personal favorite. Users have enjoyed and loved
using it ever since Ubuntu started down the Unity path.
What Mint has going for it is an outstanding desktop interface of its own, Cinnamon, which is very remindful of the classic GNOME 2.x
interface. Add to that outstanding software and hardware support, there's little question as to why Mint still appears to be the most desktop popular
Linux of all.
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Distribution of Linux
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If you're new to Linux, you don't want to download the
kernel - a component in a working Linux system.
Instead, you want what is called a distribution of
Linux, which is a complete Linux system there are
over 250 varieties of LINUX
There are numerous distributions available for
download on the Internet as well as for purchase
from various vendors http://www.linuxiso.org/
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some are general-purpose, and some are optimized for
specific uses.
mirrors of several distributions available at
mirrors.kernel.org
To install Linux visit
http://www.linux.org/docs/beginner/install.html
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Linux growth
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http://www.linuxdevices.com/ - Linux related articles
http://www.apache.com/ - Apache’s projects Web site
http://www.gnu.org - GNU website
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IBM is the Linux market leader
- 30% share vs. HP at 26% and vs. Dell at 15%
Took market share from both HP and Dell in Linux x86 revenue in 2004 (surpassin
Dell for the first time)
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http://www.netmarketshare.com/os-market-share.aspx?qprid=9 !!!
http://www.netmarketshare.com/operating-system-market-share.aspx?qprid=10 !!!! - OS
market share
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Linux growth
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Linux in 2005
 New 2.6 kernel addresses both scalability and linear performance
issues
Linux 3.1 (stable) as of 10/23/2011
http://linux.softpedia.com/progChangelog/Linux-Kernel-Stable-Changelog-1960.html - what’s new
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Linux stable kernels 3.0.43, 3.4.11, and 3.5.4 as of 14 Sep
2012
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Linux growth
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Reliability remains outstanding
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Note: reliability is highly dependent on systems manufacturer
Availability/failover extensions can now be readily
found
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failover - the transfer of operation from a failed component (e.g.,
controller, disk drive) to a similar, redundant component to
ensure uninterrupted data flow and operability
LINUX can be received:
- From Linux suppliers such as Red Hat, Novell (SuSE), or other
United Linux suppliers
From traditional hardware/software vendors such as
Oracle, IBM and HP
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HP offers open source and Linux solutions for the largest enterprises
to small and medium businesses.
- From point product failover software makers
- From grid suppliers (in the form of distributed resource
management software)
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Linux growth
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Linux is, today, a solid enterprise-class environment
with a rich infrastructure ecosystem
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Needs improvement in packaged applications support
value Linux over Windows in terms of
 security,
 low cost, and
 reliability.”
Red Hat Enterprise Linux is the leading platform for
open source computing.
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It is sold by subscription, delivers continuous value and is
certified by top enterprise hardware and software vendors.
From the desktop to the datacenter, Enterprise Linux couples the
innovation of open source technology and the stability of a
true enterprise-class platform.
The Fedora Project (2002-2005) is a Red Hat sponsored and
community-supported open source project with the goal of working
with the Linux community to build a complete, general purpose OS
from free software.
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Linux growth
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UNIX and Linux System Administration Handbook, 4e (Nemeth
et al ISBN 0131480057) has long been hailed as the all-in-one
reference for UNIX and Linux system administration.
The book goes beyond the "what" and "how" to explain the
"why" of system administration. This edition adds extensive new
coverage reflecting the realities of today's IT environments, and
anticipates tomorrow's.
The book has been thoroughly updated to cover today's leading Linux
and Unix platforms, including modern versions of Red Hat Enterprise
Linux, openSUSE, and Ubuntu; Solaris and OpenSolaris 11; HPUX 11i v3, and even AIX 6.1.
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LINUX
http://en.wikipedia.org/wiki/Linux:
 It is a leading operating system on servers
and other big iron systems such as
mainframe computers and
supercomputers:more than 90% of today's
500 fastest supercomputers run some
variant of Linux, including the 10 fastest.
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