Chapter 1 - An introduction to FreeBSD

Synopsis (1.1)

Thank you for your interest in FreeBSD!

The following chapter covers various aspects of the FreeBSD Project, such as its history, goals, development model, and so on.

After reading this chapter, you will know:

Welcome to FreeBSD (1.2)

FreeBSD is a 4.4BSD-Lite based operating system for Intel (x86 and Itanium®), AMD64, ARM®, and Sun UltraSPARC® computers. Ports to other architectures are also under way. You can also read about the history of FreeBSD, or the current release. If you are interested in contributing something to the Project (code, hardware, funding), see the Contributing to FreeBSD article.

What Can FreeBSD Do? (1.2.1)

FreeBSD has many noteworthy features. Some of these are:

FreeBSD is based on the 4.4BSD-Lite release from Computer Systems Research Group (CSRG) at the University of California at Berkeley, and carries on the distinguished tradition of BSD systems development. In addition to the fine work provided by CSRG, the FreeBSD Project has put in many thousands of hours in fine tuning the system for maximum performance and reliability in real-life load situations. FreeBSD offers performance and reliability on par with commercial offerings, combined with many cutting-edge features not available anywhere else.

The applications to which FreeBSD can be put are truly limited only by your own imagination. From software development to factory automation, inventory control to azimuth correction of remote satellite antennae; if it can be done with a commercial UNIX® product then it is more than likely that you can do it with FreeBSD too! FreeBSD also benefits significantly from literally thousands of high quality applications developed by research centers and universities around the world, often available at little to no cost. Commercial applications are also available and appearing in greater numbers every day.

Because the source code for FreeBSD itself is generally available, the system can also be customized to an almost unheard of degree for special applications or projects, and in ways not generally possible with operating systems from most major commercial vendors. Here is just a sampling of some of the applications in which people are currently using FreeBSD:

Networking: Need a new router? A name server (DNS)? A firewall to keep people out of your internal network? FreeBSD can easily turn that unused PC sitting in the corner into an advanced router with sophisticated packet-filtering capabilities.

Software Development: The basic FreeBSD system comes with a full complement of development tools including a full C/C++ compiler and debugger suite. Support for many other languages are also available through the ports and packages collection.

FreeBSD is available to download free of charge, or can be obtained on either CD-ROM or DVD. Please see Appendix A, Obtaining FreeBSD for more information about obtaining FreeBSD.

Who Uses FreeBSD? (1.2.2)

FreeBSD's advanced features, proven security, predictable release cycle, and permissive license have led to its use as a platform for building many commercial and open source appliances, devices, and products. Many of the world's largest IT companies use FreeBSD:

Wheel Systems - The FUDO security appliance allows enterprises to monitor, control, record, and audit contractors and administrators who work on their systems. Based on all of the best security features of FreeBSD including ZFS, GELI, Capsicum, HAST, and auditdistd.

FreeBSD has also spawned a number of related open source projects:

FreeBSD is also used to power some of the biggest sites on the Internet, including:

About the FreeBSD Project (1.3)

The following section provides some background information on the project, including a brief history, project goals, and the development model of the project.

A Brief History of FreeBSD (1.3.1)

The FreeBSD Project had its genesis in the early part of 1993, partially as an outgrowth of the Unofficial 386BSDPatchkit by the patchkit's last 3 coordinators: Nate Williams, Rod Grimes and Jordan Hubbard.

The original goal was to produce an intermediate snapshot of 386BSD in order to fix a number of problems with it that the patchkit mechanism just was not capable of solving. The early working title for the project was 386BSD 0.5 or 386BSD Interim in reference of that fact.

386BSD was Bill Jolitz's operating system, which had been up to that point suffering rather severely from almost a year's worth of neglect. As the patchkit swelled ever more uncomfortably with each passing day, they decided to assist Bill by providing this interim “cleanup” snapshot. Those plans came to a rude halt when Bill Jolitz suddenly decided to withdraw his sanction from the project without any clear indication of what would be done instead.

The trio thought that the goal remained worthwhile, even without Bill's support, and so they adopted the name "FreeBSD" coined by David Greenman. The initial objectives were set after consulting with the system's current users and, once it became clear that the project was on the road to perhaps even becoming a reality, Jordan contacted Walnut Creek CDROM with an eye toward improving FreeBSD's distribution channels for those many unfortunates without easy access to the Internet. Walnut Creek CDROM not only supported the idea of distributing FreeBSD on CD but also went so far as to provide the project with a machine to work on and a fast Internet connection. Without Walnut Creek CDROM's almost unprecedented degree of faith in what was, at the time, a completely unknown project, it is quite unlikely that FreeBSD would have gotten as far, as fast, as it has today.

The first CD-ROM (and general net-wide) distribution was FreeBSD 1.0, released in December of 1993. This was based on the 4.3BSD-Lite (“Net/2”) tape from U.C. Berkeley, with many components also provided by 386BSD and the Free Software Foundation. It was a fairly reasonable success for a first offering, and they followed it with the highly successful FreeBSD 1.1 release in May of 1994.

Around this time, some rather unexpected storm clouds formed on the horizon as Novell and U.C. Berkeley settled their long-running lawsuit over the legal status of the Berkeley Net/2 tape. A condition of that settlement was U.C. Berkeley's concession that large parts of Net/2 were “encumbered” code and the property of Novell, who had in turn acquired it from AT&T some time previously. What Berkeley got in return was Novell's “blessing” that the 4.4BSD-Lite release, when it was finally released, would be declared unencumbered and all existing Net/2 users would be strongly encouraged to switch. This included FreeBSD, and the project was given until the end of July 1994 to stop shipping its own Net/2 based product. Under the terms of that agreement, the project was allowed one last release before the deadline, that release being FreeBSD 1.1.5.1.

FreeBSD then set about the arduous task of literally re-inventing itself from a completely new and rather incomplete set of 4.4BSD-Lite bits. The “Lite” releases were light in part because Berkeley's CSRG had removed large chunks of code required for actually constructing a bootable running system (due to various legal requirements) and the fact that the Intel port of 4.4 was highly incomplete. It took the project until November of 1994 to make this transition, and in December it released FreeBSD 2.0 to the world. Despite being still more than a little rough around the edges, the release was a significant success and was followed by the more robust and easier to install FreeBSD 2.0.5 release in June of 1995.

Since that time, FreeBSD has made a series of releases each time improving the stability, speed, and feature set of the previous version. For now, long-term development projects continue to take place in the 10.X-CURRENT (trunk) branch, and snapshot releases of 10.X are continually made available from the snapshot server as work progresses.

FreeBSD Project Goals (1.3.2)

Contributed by Jordan Hubbard.

The goals of the FreeBSD Project are to provide software that may be used for any purpose and without strings attached. Many of us have a significant investment in the code (and project) and would certainly not mind a little financial compensation now and then, but we are definitely not prepared to insist on it. We believe that our first and foremost “mission” is to provide code to any and all comers, and for whatever purpose, so that the code gets the widest possible use and provides the widest possible benefit. This is, I believe, one of the most fundamental goals of Free Software and one that we enthusiastically support.

That code in our source tree which falls under the GNU General Public License (GPL) or Library General Public License (LGPL) comes with slightly more strings attached, though at least on the side of enforced access rather than the usual opposite. Due to the additional complexities that can evolve in the commercial use of GPL software we do, however, prefer software submitted under the more relaxed BSD copyright when it is a reasonable option to do so.

The FreeBSD Development Model (1.3.3)

Contributed by Satoshi Asami.

The development of FreeBSD is a very open and flexible process, being literally built from the contributions of thousands of people around the world, as can be seen from our list of contributors. FreeBSD's development infrastructure allow these thousands of contributors to collaborate over the Internet. We are constantly on the lookout for new developers and ideas, and those interested in becoming more closely involved with the project need simply contact us at the FreeBSD technical discussions mailing list. The FreeBSD announcements mailing list is also available to those wishing to make other FreeBSD users aware of major areas of work.

Useful things to know about the FreeBSD Project and its development process, whether working independently or in close cooperation:

The SVN repositories

The committers list

The FreeBSD core team

Outside contributors

In summary, our development model is organized as a loose set of concentric circles. The centralized model is designed for the convenience of the users of FreeBSD, who are provided with an easy way of tracking one central code base, not to keep potential contributors out! Our desire is to present a stable operating system with a large set of coherent application programs that the users can easily install and use — this model works very well in accomplishing that.

All we ask of those who would join us as FreeBSD developers is some of the same dedication its current people have to its continued success!

Third Party Programs (1.3.4)

In addition to the base distributions, FreeBSD offers a ported software collection with thousands of commonly sought-after programs. At the time of this writing, there were over 24,000 ports! The list of ports ranges from http servers, to games, languages, editors, and almost everything in between. The entire Ports Collection requires approximately 500 MB. To compile a port, you simply change to the directory of the program you wish to install, type make install, and let the system do the rest. The full original distribution for each port you build is retrieved dynamically so you need only enough disk space to build the ports you want. Almost every port is also provided as a pre-compiled “package”, which can be installed with a simple command (pkg install) by those who do not wish to compile their own ports from source. More information on packages and ports can be found in Chapter 4, Installing Applications: Packages and Ports.

Additional Documentation (1.3.5)

All supported FreeBSD versions provide an option in the installer to install additional documentation under /usr/local/share/doc/freebsd during the initial system setup. Documentation may also be installed at any later time using packages as described in Section 23.3.2, “Updating Documentation from Ports”. You may view the locally installed manuals with any HTML capable browser using the following URLs:

The FreeBSD Handbook

The FreeBSD FAQ

You can also view the master (and most frequently updated) copies at https://www.FreeBSD.org/.

PaulWebster/Handbook/Introduction (last edited 2022-01-23T01:51:06+0000 by KubilayKocak)