Linux Allgemein
Einleitung
Aufbau und Philosophie
Distributionen, Support
Anwendungsbereiche
Einleitung
- Linux is an affordable, good, stable, reliable and secure Operating System for Desktop and Server applications.
- Linux is well suited for academic as well as for commercial usage.
- Linux is something special, not experienced so far in the big OS space.
- Linux is not thinkable without the Internet.
- Linux is very important to keep the OS market competitive in the future.
- Linux is the only competitor of Microsoft's operating systems, especially Windows NT / XT.
- Linux is a philosophy, but Linux is also a software
Linux ist ein Unix-Derivat
- 1969: Ken Thompson entwickelt UNIX bei den Bell Labs.
- ~1985: Andrew Tanenbaum entwickelt Minix.
- 1991: Linus Torvalds beginnt an einem Minix Derivat,
genannt "Linux", zu arbeiten.
- 1991: erster stabiler Kernel. Linux verbreitet sich im Internet.
- 1993/1994: erste Linux Distributionen auf CD-ROM.
- 1998: Commercial hardware companies
Siemens, HP, Dell, Fujitsu-Siemens und IBM
announce Linux on their plattforms.
- 1999: After SAPs announcement to port SAP R/3 to linux,
the following producers of DB / Applications software are
in the linux boat: Oracle, Informix, Sybase, Ingres, Netscape.
Systemarchitektur
- Layers model of a Linux Hardware/Software - System
- Last kernel release: v2.2.6, v2.4.20
- Last development kernel: v2.1.132, v.2.5.10
- Current innovation cycle:
- Since 8. January (version 2.2.0) 7 new stable kernel releases
- every 13 days a new kernel release . :-)
GNU = GNU is Not Unix
- Tools available for all major platforms
- Products under GNU Public License (GPL)
- Standadization of Software
- High Reliability
- High Functionality
- GNU Public Licence (GPL):
- Free Availability of Source Code
- Free passing on of the complete Software Package
Hardware Platforms
Processors:
- Intel x86, IA68
- AMD x86, Opteron
- DEC Alpha
- MIPS
- PowerPC / PowerMAC
- Sun SPARC / Ultra Sparc
- Motorola m68k
- ARM
Systems:
- IBM AS/400, RS/6000, S/390
- Siemens Celsius, Primergy
- SGI Indy
- HP (Compaq) Alpha Server
- NeXT
- 3Com Palm II/III
Development Philosophy
- Release early, release often - L. Torvalds
- Delegate everything you can - L. Torvalds
- Treating the users as co-developers means rapid code improvement and effective debugging.
- Given a large enough beta-tester and co-developer base, almost every problem will be characterized fast and the fix obviously to someone.
- Debugging is parallelizable - Jeff Dutky, Opensource Movement
- KISS - Keep It Small and Simple
- Listen to the users. Sometimes their ideas are better.
- Recognizing good ideas from others is very important.
- The internet is an ideal tool for development of software according to the Bazaar-Model.
- In contrast Microsoft Software is developed according to the Cathedral-Model.
- Linux is developed by the community.
- Anyone making use of the software must agree to give everyone else the rights to use, modify, and redistribute the programīs code or any program derived from it but only if the distribution terms are unchanged.
Business Analysts:
- GartnerGroup 01/99: "The ground swell of interest in Linux [..] is poised to gain momentum if sincere vendor support becomes available"
- GartnerGroup 01/99: "Linux vendor technical support for MSEs will only be adequate for technically knowledgeable IT organizations through 2000 (0.7 probability)."
- IDC 04/99: According to statistics from IDC, about 750,000 servers had Linux installed in 1998, an increase of 212% (NT: 36%)
- IDC 04/99: Over the next five years, Linux will grow faster than all other operating systems combined.
- Dow Jones 04/99 : The market size for Linux-related business will be between $5 billion and $20 billion in 2002.
- DH Brown 04/99: Linux comes up short when compared feature-for-feature with commercial Unix products and Windows NT, but the operating system is great for some tasks.
Distributions
RedHat
SuSE
Debian
Delix
(Ist mittlerweile in RedHat aufgegangen.)
Caldera
zum Beispiel SuSE
- Good manual
- Help files and docs on CD
- 60 Days free installation support via Email, Fax and Hotline
- SuSE-support database on the Internet (free)
- Commercial support service
Free Support
- Zero costs (if you have Internet access)
- should be managed by the system administrator
- You have to be active in Newsgroups, Mailing Lists, WWW etc.
- there is no guaranteed servic time ...
but a very high probability to get the problem fixed
Technical Support
- Community Help: The Linux Documentation Project maintains dozens
of how-to files covering every imaginable subject,
including installation, DOS emulation, networking, and using
Cyrillic characters.
- Check Out Newsgroups: Check out the wide variety of Linux-based
Usenet newsgroups, including comp.os.linux.misc, comp.os.linux.setup,
comp.os.linux.questions, and alt.os.linux.
- Other Linux Users: Linux user groups have cropped up around the globe
- Shell Out Cash: If your company needs Linux support -- even around
the clock -- it's available. Both Red Hat and SuSE offer
full-time, phone-based tech support help, either on a
per-incident or annual contract basis. In addition, there is
now support from software and hardware vendors like Siemens, IBM, HP
- Linux "common channels" support using specialized news groups
and mailing lists has a great value.
- Direct contact with the main developers
- Direct contact with users with the same problem
- Fast response and advice ( ~ 1 hour response time is common)
- An alternative to "commercial support" but without guarantees
- Hardware and Software support directly from vendors recommended
- By mission critical application 24/7 support contracts recommended
Linux as Desktop Maschine
- Office suits available (Applixware, StarOffice, Wordperfect,
KDE-Office, OpenOffice)
- Easy to use and:
- Compatibility with MS-Office (Word, PPT)
- Smart text editing and formatting available: TeX, LaTeX
- Not easy to use, but very widespread use from Scientific Users
- well suited for big documents and books
- Graphical user interface X-Windows
- Desktops KDE and Gnome
- Applications for most important tasks: Office applications,
image processing, scientific/technical, web, audio, internet tools,
software development, rendering, ...
- SAP R/3 GUI available since 12/99
- Although many applications are available, Linux needs a better
and easier installation procedures and more applications for
the normal user.
- The upcoming UnitedLinux and SuSE 8.x seem to be
going into this direction
- Linux on the Desktop only for advanced users.
- L. Torvalds: "... The desktop market is the hardest by far".
Linux as Server: Intranet + Internet
- Samba (in Windows-Networks)
- NFS (Network File System)
- Print-Server
- Email-Server (with IMAP or POP3)
- Central Backup-Server
- Firewall between LAN and Internet
- FTP (File Transfer Protocol)
- WWW-Server mit Apache (HTTP), PHP und MySQL
- News-Server
- Email-Server
- Name-Server (DNS)
- Linux is great as operating system in LANs and in the Internet
High Performance Linux Cluster
- Linux Clusters in the TOP500, z.B. Helics
- hpcLine of Fujitsu-Siemens (Aachen, Kaiserlautern and Paderborn)
- Do it yourself Supercomputers (half the performance, 10% of the price)
- "Supercomputing for the masses" (Robin Miller in TechSightings)
© Universität Mannheim, Rechenzentrum, 1999-2003.
Heinz Kredel
Last modified: Thu Mar 20 17:15:58 CET 2003