Key Concepts - UNIX Administration: Class 1

  • Although it is a trademark, UNIX is a general term used to describe a class of computer operating systems based on the original UNIX operating system developed at Bell Labs in 1969.

  • There are many different UNIX "flavors" distributed by a number of companies. Some of the most popular UNIX flavors include Sun Solaris, HP's HP-UX and a number of Linux-based distributions.

  • UNIX is a multi-user time-sharing operating system that allows multiple users to share a computer's CPU power.

  • Linux comes in many different packages that are sold by commercial entitites. These distributions are marketed by companies such as RedHat, Mandrake, SuSe, Caldera, etc. You want to pay for a commercial distributions's media, manuals, support, etc. However, Linux is licensed under the GNU Public License - which means it's free for download.

  • Before installing a UNIX-like OS on your machine, it is very important to be sure your computer hardware is compatible with your UNIX Operating system. Compatibility issues are usually not that much of a problem when working with commercial UNIX flavors, such as Sun Solaris for Sparc or DEC UNIX because these distributions have been written to run on very specific hardware. Since PC hardware varies so greatly, Linux, BSD-based UNIX flavors and other PC UNIX flavors, such as Sun Solaris for x86, usually have a very specific list of hardware that is supported. Generic peripherals, such as hard drives, floppy drives, etc. are usually fully supported. But more specific equipment, such as video cards, network cards, sound cards and SCSI controllers must be explicitly supported by the UNIX distribution to work. Check the hardware compatibility list for your UNIX vendor before you start installation. The RedHat hardware compatibility list can be found at

  • When installing a UNIX-based OS on a PC, you must start the installation by booting directly into the OS installation program. If you PC supports booting via a CD-ROM drive, you can set your BIOS to look for a bootable CD-ROM. If you PC does not support bootable CD-ROM drives, you must create a boot floppy, which may be supplied to you if you purchase a UNIX distribution.

  • Partitioning is a concept where we divide a hard drive into logical units that make one drive appear to be multiple drive. When we partition a UNIX hard drive, a popular partition layout might be similar to this:
    There is also another REQUIRED partition - the SWAP partition - that the system uses as virtual memory when it runs out of physical RAM. You should create a swap parition that is at least 2 times the amount of RAM installed in your computer.

  • Before installing your UNIX operating system, it's important to know the following.
  • The user "root" is the "Super User", who has the permission to make all administrative changes to your system. You can become the root user by logging in as root directly on your system's console or by logging in as another user and issuing the 'su' command at the command prompt and providing the root password.