Unix Systems Administration 1Y. K. Chang UNIX History : Bell Lab joined with GEC and Project MAC of MIT to develop Multics: multi-user and data-sharing environment : originated as a research at AT&T Bell Lab –Ken Thompson, Dennis Ritchie, Brian Kernighan, and others sketched an early version of UNIX file system on GECOS system for PDP-7. –UNIX named by Kernighan, a pun of Multics.

Unix Systems Administration 2Y. K. Chang UNIX History : UNIX is moved to PDP-11, 16K for system, 8k for users program, a disk of 512k, and limit of 64k per file. –Thompson come up a language B after BCPL when implementing a Fortran compiler –Ritchie developed language B into C language : Unix was rewritten in C, a tremendous impact on its acceptance among outside users.

Unix Systems Administration 3Y. K. Chang UNIX History : V6 released & available free to universities : Berkeley UNIX began with CSRG (Comp. Sys. Research Group) licensed V6 from AT&T –Berkeley releases are called BSD (Berkeley Software Distribution) with 1BSD for PDP-11 and culminated 4.4BSD in 1993, and 4.4BSD-lite –A license from AT&T was required to use BSD –AT&T source code license is expensive for government lab and commercial entities, although is cheap for universities

Unix Systems Administration 4Y. K. Chang UNIX History : V7 available, basis of later versions 4 After V7, AT&T created USG (UNIX Support Group), later USL (UNIX system Lab) for commercial products. 4 Bell Lab and USG’s efforts diverge, where USL’s releases, System III & V have more impact : AT&T sold UNIX operations to Novell, repackage System V as UnixWare, not popular, and have all UNIX loyalty

Unix Systems Administration 5Y. K. Chang UNIX History 4 Berkeley set the long-term goal of removing AT&T’s code from BSD –before complete, funding suspended and CSRG disbanded –CSRG released the second collection of AT&T- free code (Net/2). –Companies like BSDI took it.

Unix Systems Administration 6Y. K. Chang UNIX History 4 Lawsuits between AT&T for trade secret and Berkeley for contract violation began. At the same time, AT&T sued BSDI for using Net/2 as the basis of its product : lawsuits dropped. Berkeley announced 4.4BSD-Lite, freely distributable.

Unix Systems Administration 7Y. K. Chang UNIX History 4 Throughout 80s, vendors based on AT&T or BSD developed their UNIX systems independently 4 standardized by many vendors, but another flavor of Unix.

Unix Systems Administration 8Y. K. Chang UNIX History 4 ATT and BSD Unix systems 4 Novell’s UnixWare and BSDI’s BSD/OS are the most generic systems 4 Sun Solaris 2.X is an ATT Unix. Sun’s older systems are BSD-based, SunOS. 4 DEC’s OSF/1 based on Mach is a BSD. 4 SGI’s IRIX is a ATT. 4 HP’s HP-UX is a ATT

Unix Systems Administration 9Y. K. Chang UNIX History 4 NetBSD, 386BSD, FreeBSD, and Linux are based on Net/2 from Berkeley. 4 SCO UNIX, The Santa Cruz Operation, is based on a older version of the AT&T Unix, SVR3.2 4 Solaris 2.7, IRIX 5.2, OSF/1 2.0  HP-UX 11.0, SunOS 4.1.3, BSD/OS 1.1  Red Hat Linux 6.2, FreeBSD 3.4

Unix Systems Administration 10Y. K. Chang Linux and Linux variants 4 Developed by Linus Torvalds 4 Varaints –Caldera Linux –Corel Linux –Debian Linux –Kondara Linux –Red Hat Linux –Mandrake Linux –SuSE Linux –Turbo Linux –Vector Linux

Unix Systems Administration 11Y. K. Chang Linux vs. MS NT 4 Pro: –Linux and Linux variants are considerably less expensive to run. Most versions of Linux are free. Especially when looking at the Microsoft Windows NT with multiple licenses. –Issues are generally resolved more quickly than Windows NT with open source code.

Unix Systems Administration 12Y. K. Chang Linux vs. MS NT 4 Con: –Overall Windows NT has a larger availability of software and drivers. However, because of the popularity of Linux, software developers and hardware manufactures are also releasing software support and drivers for their devices. –Windows NT software is generally compatible with other versions of Windows / Windows NT. However, XP is not compatible  so.NET –Overall Windows NT is generally easier then Linux and has a wider audience familiar with the functionality and control of it.

Unix Systems Administration 13Y. K. Chang Linux vs. UNIX 4 Pro: –Linux has a larger availability of software and drivers than most versions of UNIX. Variants of UNIX such as SUN Solaris may have about the same or more availability of software and drivers than some versions of Linux. –Linux issues and bugs generally are always fixed extremely fast and will likely be fixed before an issue in UNIX is fixed. –Linux is available for free or for a small cost. Most versions of UNIX or Variants of UNIX can be very expensive. It is important to note that versions of SUN Solaris are available for free for end-users.

Unix Systems Administration 14Y. K. Chang Linux vs. UNIX 4 Con: –Many versions of UNIX are a project of a centralized company and all issues, information and support are maintained at one central location. –Many versions of UNIX allow for very large scalability and maintain reliability. –

Unix Systems Administration 15Y. K. Chang Homework #1 4 This homework requires you to do a simple survey on Unix. After that you will know how many different versions of Unix OSes exist. –Find out what are the latest version of the Unix mentioned in the class. –How many Linux variants exist in the world?