GNU and Linux

What is Linux? 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 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 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 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 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 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 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 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 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 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 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 Choose which OS to boot. Linux can access stuff on the windows side

A Virtual Machine

Or

Types of Virtual Machines 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 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? 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.

(or Mac) VMWare – Owned by Dell. Commercial product for Windows, Linux and Mac systems. Workstation Player can be downloaded for free from http://www.vmware.com/products/player/playerpro-evaluation.html VirtualBox – Owned by Oracle. Versions for Windows, Mac, and Linux Can be downloaded for free from https://www.virtualbox.org/

without a VM 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.