GNU and Linux
What is Linux?
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An operating system, similar to Windows 7, 8,
and 10 or OSX for Apple.
Was an attempt to give PC users an operating
system similar to Unix on larger computers.
Uses “open source”
When you get a copy of Linux, you get the
source code, so if you don't like what you have,
you can change it.
“Flavors” of Linux
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There are quite a few “flavors” of Linux
Redhat Fedora, OpenSUSE, Ubuntu, Solus,
Mint, Debian, Raspbian, and others
All use the same kernel, but have different
utilities and default setups
Linux systems you may not know
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Android – Google's version of Linux for all kinds
of things.
ChromeOS – for Chromebook computers. Only
runs when connected to the internet.
Other open source operating
systems
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Berkeley Software Distribution
FreeBSD, NetBSD, OpenBSD,
PC-BSD
These guys were modified into OSX.
Licensing for these systems is a little different
than the GNU license.
Unix to Linux
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Unix developed by AT&T (Bell Labs)
AT&T gave copies free to universities
But wanted $$$ for commercial applications
Lots of graduates from universities wanted to
keep using Unix once they were in the real
world.
PC's come along
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GNU (GNU's not Unix) provides many of the
Unix apps
Linus Torvalds writes the Linux kernel (with a lot
of help from all around the world)
Where Linux is used
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Servers, like mail servers, Google servers, web
servers, network accessible storage devices.
99% of the world's supercomputers run Linux.
Embedded systems, like the computers in your
car, control devices, “internet of things” devices
Revive an old computer by loading PuppyLinux
or Lubuntu on it.
Linux malware
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There ain't none in the “wild”
Unix systems were originally multiple
users, so protection was built in.
Each flavor of Linux requires a different attack.
“There has not yet been a single widespread
Linux virus or malware infection of the type that
is common on Microsoft Windows; this is
attributable generally to the malware's lack of
root access and fast updates to most Linux
vulnerabilities.”
Where to get Linux
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Download from any number of sites
https://www.ubuntu.com/download
https://getfedora.org/
https://www.opensuse.org/
https://www.debian.org/
How to load Linux on your PC
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Live CD – put CD in your DVD reader, boot
system, it runs Linux, take out CD, it runs
Windows
Dual boot – Two or more operating systems on
your computer. You pick which one you want.
Limited by disk space.
Virtual Machine – Your host OS runs a virtual
machine guest which runs its own (possibly
different) OS.
Run a Live CD
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Boot the computer with the Live CD
It loads and runs the operating system on the
CD
May or may not be able to access the computer
disks
Dual Boot System
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Choose which OS to boot.
Linux can access stuff on the windows side
A Virtual Machine
Or
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Types of Virtual Machines
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Simulator – Runs a totally different kind of
computer. For example, run an IBM 1401
simulator on your PC (this is still done in some
financial institutions)
Emulator – Run the same kind of computer on
your host computer. Run a Linux OS as a guest
on your windows machine.
Wine (Windows emulator) – Runs a program
that pretends to be Windows. Available for
Linux and Apple machines.
What is a Virtual Machine used for
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For most programs, the computer spends most
of it's time idle.
Run several VMs at a time, and each VM runs
as a seperate computer and operating system.
Each program can run in a different operating
system (Window 10 host runs Redhat Linux,
Windows XP, OS/2.
Can run multiple servers on one machine, and
switch to another machine as needs require.
What is needed for a VM?
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A good processor, with more than average
speed.
Enough disk space for two operating systems
Enough memory for two operating systems
Host operating system (Linux, OSX, Windows)
Guest Operating system (Windows 7, OS/2,
Linux, DR-DOS). Remember, some of these
may require you to have a license.
Run Linux on your Windows PC
(or Mac)
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VMWare – Owned by Dell. Commercial product
for Windows, Linux and Mac systems.
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Workstation Player can be downloaded for free from
http://www.vmware.com/products/player/playerproevaluation.html
VirtualBox – Owned by Oracle. Versions for
Windows, Mac, and Linux
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Can be downloaded for free from
https://www.virtualbox.org/
Run Windows on Mac or Linux
without a VM
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Crossover Office (cxoffice) from codeweavers
will run some Windows programs.
Makes use of a utility program called WinE
(Windows Emulator).
Cxoffice starts the target program and pretends
to be the Windows operating system.
Translates the commands from Windows to
Linux or OSX.
Not all programs run completely correctly.