The Debian GNU/Linux FAQ Susan G. Kleinmann (sgk@debian.org), Sven Rudolph (sr1@inf.tu-dresden.de), and Joost Witteveen (joostje@debian.org) 28 December 1996 1. Meta-questions 1.1. In what format is this document written? This document was written using the Linuxdoc-SGML DTD. The Linuxdoc-SGML system can be used to create files in a variety of other formats, e.g., GNU info, HTML, LaTeX, TeX .dvi format, and PostScript (TM) files. sdc (SGML Document Compiler) is an alternative system that in some cases produces better output than Linuxdoc-SGML. Linuxdoc-SGML and sdc are available as Debian packages. 1.2. Where do I get the latest version of this document? The latest version of this document can be viewed in HTML format at the Debian home page ( http://www.debian.org/FAQ/ ) . It is also available in HTML, PostScript, GNU info and plain text format at the Debian FTP Server ( ftp://ftp.debian.org/debian/ ) and any of its mirrors ( http://www.debian.org/ftplist.html ) in the directory doc/FAQ/. The original SGML files used to create this document are available as part of the Debian package called doc-debian_VVV-RRR.deb, where VVV is the latest version number and RRR is the latest revision number. This package is normally stored in the directory stable/binary-all/doc/. The linuxdoc-sgml package contains tools to transform this document into one or more other formats, as required by the user: GNU info files, HTML, LaTeX, TeX .dvi format, and PostScript. 1.3. Where do I send questions, corrections, etc. about this document? Comments on this document are welcome. Please send e-mail to debian-faq@debian.org. 1.4. (How) Can I redistribute this file? This document is copyright 1996 by SPI (see section Software in the Public Interest (14.3.1)). Permission is granted to make and distribute verbatim copies of this document provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this document under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this document into another language, under the above conditions for modified versions, except that this permission notice may be included in translations approved by the Free Software Foundation instead of in the original English. 1.5. What information resources were used to obtain the questions and answers presented here? This FAQ previously was maintained by J.H.M. Dassen (jdassen@wi.LeidenUniv.nl) and Chuck Stickelman (stick@richnet.net). Parts of the information came from o The Debian-1.1 release announcement ( http://www.debian.org/1.1/release.html ) by Bruce Perens. o The Linux FAQ ( http://www.cl.cam.ac.uk/users/iwj10/linux-faq/ ) by Ian Jackson ( http://www.cl.cam.ac.uk/users/iwj10/ijackson.html ) . o The Debian Mailing List Archives ( ftp://ftp.debian.org/debian/debian-lists/ ) o The dpkg programmers' manual and the Debian policy manual (12.1) o The many developers, volunteers, and beta testers. o The flaky memories of its authors. The authors would like to thank all those who helped make this document possible. 2. Definitions and Overview 2.1. What is Debian GNU/Linux? Debian GNU/Linux is a particular distribution of the Linux operating system, and numerous packages that run on it. In principle, users could obtain the Linux kernel via the Internet or from elsewhere, and compile it themselves. They could then obtain source code for many applications in the same way, compile the programs, then install them into their systems. For complicated programs, this process can be not only time-consuming but error-prone. To avoid it, users often choose to obtain the operating system and the application packages from one of the Linux distributors. What distinguishes the various Linux distributors are the software, protocols, and practices they use for packaging, installing, and tracking applications packages on users' systems, combined with installation and maintenance tools, documentation, and other services. Debian GNU/Linux is the result of a volunteer effort to create a free, high-quality Unix-compatible operating system, complete with a suite of applications. The idea of a free Unix-like system originates from the GNU project, and many of the applications that make Debian GNU/Linux so useful were developed by the GNU project. Debian was created by Ian Murdock in 1993, initially under the sponsorship of the Free Software Foundation's GNU project. Today, Debian's developers think of it as a direct descendent of the GNU project. Debian GNU/Linux is o full featured: Debian includes more than 700 software packages at present. Users can select which packages to install; Debian provides a tool for this purpose. You can find a list and descriptions of the packages currently available in Debian at any of the Debian mirror sites. o free to use and redistribute: There is no consortium membership or payment required to participate in its distribution and development. All packages that are formally part of Debian GNU/Linux are free to redistribute, usually under terms specified by the GNU General Public License. The Debian FTP archives also carry approximately 50 software packages (in the non-free and contrib directories at the FTP archives), which are distributable under specific terms included with each package. o dynamic: With about 120 volunteers constantly contributing new and improved code, Debian is evolving rapidly. New releases are planed to be made about every three months, and the FTP archives are updated daily. Though Debian itself is free software, it is a base upon which value-added Linux distributions can be built. By providing a reliable, full-featured base system, Debian provides Linux users with increased compatibility, and allows Linux distribution creators to eliminate duplication-of-effort and focus on the things that make their distribution special. 2.2. OK, now I know what Debian is...what is Linux!? In short, Linux is the kernel of a Unix-like operating system. It was originally designed for 386/486/Pentium PCs; now, ports to other systems, including multi-processor systems, are under development. Linux is written by Linus Torvalds and many computer scientists around the world. Besides its kernel, a Linux system usually has: o a file system that follows the Linux Filesystem Hierarchy Standard ( http://www.pathname.com/fhs/ ) . o a wide range of Unix utilities, many of which have been developed by the GNU project and the Free Software Foundation. The combination of the Linux kernel, the filesystem, the GNU and FSF utilities, and the other utilities are designed to achieve compliance with the POSIX (IEEE 1003.1) standard; see source code compatibility (4.2). For more information about Linux, see Michael K. Johnson's INFO-SHEET ( ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/INFO-SHEET ) and META-FAQ ( ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/META-FAQ ) . 2.3. What is the difference between Debian and other Linux distributions? Three key features distinguish Debian from other Linux distributions: The Debian package maintenance system: The entire system, or any individual component of it, can be upgraded in place without reformatting, without losing custom configuration files, and (in most cases) without rebooting the system. Most Linux distributions available today have some kind of package maintenance system; the Debian package maintenance system (6) is unique and particularly robust. Open development: Whereas other Linux distributions are developed by individuals, small, closed groups, or commercial vendors, Debian is the only Linux distribution that is being developed cooperatively by many individuals through the Internet, in the same spirit as Linux and other free software. More than 120 volunteer package maintainers are working on over 700 packages and improving Debian GNU/Linux. The Debian developers contribute to the project not by writing new applications (in most cases), but by packaging existing software according to the standards of the project, by communicating bug reports to upstream developers, and by providing user support. See also additional information on how to become a contributor (14.1). The Bug Tracking System: The geographical dispersion of the Debian developers required sophisticated tools and quick communication of bugs and bug-fixes to accelerate the development of the system. Users are encouraged to send bugs in a formal style, which are quickly accessible by WWW archives or via e-mail. See additional information in this FAQ on the management of the Bug Log (13). 2.4. How does the Debian project fit in or compare with the Free Software Foundation's GNU project? The Debian system builds on the ideals of free software first championed by the Free Software Foundation ( http://www.gnu.ai.mit.edu/ ) and in particular by Richard Stallman. FSF's powerful system development tools, utilities, and applications are also a key part of the Debian system. The Debian Project is a separate entity from the FSF, however we communicate regularly and cooperate on various projects. The FSF explicitly requested that we call our system "Debian GNU/Linux", and we are happy to comply with that request. The FSF's long-standing objective is to develop a new operating system called GNU based on HURD ( http://www.gnu.ai.mit.edu/software/hurd/hurd.html ). 2.5. How does one pronounce Debian and what does this word mean? The project name is pronounced Deb'-ian, with a short e, and emphasis on the first syllable. This word is a contraction of the names of Debra and Ian Murdock, who founded the project. (Dictionaries seem to offer some ambiguity in the pronunciation of Ian (!), but Ian prefers ee'-an.) 3. Hardware Requirements 3.1. On what architectures/systems does Debian GNU/Linux run? Debian GNU/Linux includes complete source-code for all of the included programs, so it should work on all systems which are supported by the Linux Kernel; see the Linux FAQ ( http://www.cl.cam.ac.uk/users/iwj10/linux-faq/ ) for details. The current Debian GNU/Linux release contains a complete, binary distribution for the i386 architecture; this covers PCs based on Intel-compatible processors, including Intel's80386, 80486, Pentium, and Pentium Pro, and compatible processors by AMD, Cyrix and others. The development of binary distributions of Debian 1.2 for the m68k architecture (Motorola 680x0 processors for x>=2; with MMU) is currently underway, and ports to Alpha, SPARC, and MIPS processors are expected to follow. 3.2. What hardware is assumed by the stock Debian GNU/Linux boot disks? The configuration file used to build Debian GNU/Linux' standard distribution kernel assumes an 80386 CPU, and includes support for PCMCIA cards SCSI cards for which there exist Linux drivers. Support for network interface card is provided by loadable modules, so there is no need to compile these drivers into the kernel. 3.3. What amount of disk space is recommended? A generous installation, sufficient to accommodate a few users, X Window System software, and several large applications, might require disk partitions at least as large as: o 50 MBytes for the root directory (/) o 500 MBytes for /usr o 50 MBytes for swap space o 50 MBytes for each home directories o 100 MBytes for /tmp o 100 MBytes for /var The optimum disk space allocated for swap depends critically on the way the system will be used. Many people just choose to set aside twice as much disk space as they have RAM space. Systems with large RAM may not need so much swap space, especially if there are only a few users. The installation process supports systems with no swap space. 3.3.1 But how much RAM and disk space are absolutely essential? These minimal requirements are sufficient for a system without X11 and only 1 or 2 users: o 15 MBytes of disk space for the base system; this provides a minimally-functioning Unix system, but includes no application programs and no network support. o 100 MBytes of disk space for a standard system running applications on the console (i.e., without an X11 interface). o 150 MBytes of disk space for a standard system running applications with the X Window System. o 300 MBytes and more for all the optional programs (You probably do not need all of these programs.) Debian Linux can be installed on systems with only 4 MBytes of RAM. The latest installation disks are especially organized to provide an easy installation path for machines with small memories. Some users report success at using Debian Linux to convert PCs having limited RAM (and disk space) into X terminals. An 80386-based system with only 4 MBytes of RAM and 40 MBytes disk space has been used to run Debian Linux in this way; i.e., both networking and basic X11 server functions operated satisfactorily. This mode of operation even works if 1 MByte of the RAM is used as a ramdisk when the machine is booted, implying that only 3 Mbytes of RAM is absolutely essential for using Debian Linux on a PC in order to use it as an X server. This mode of operation requires a swap partition; without it, the system will not even go into multi-user mode. 3.4. How should I partition my drive? Partitioning a drive has the disadvantage that drive space can be used much less flexibly than an unpartitioned drive. Most users find, however, that this disadvantage is more than offset by the fact that damage to a filesystem on a partitioned disk is usually limited to a single partition. Furthermore, backups of a partitioned hard disk can be more easily managed because the files that change most frequently are likely to be localized to a single partition. A user with a 1.6 GByte drive has concluded after a survey of Debian users that it is reasonable to design a partitioning scheme that closely follows the Filesystem Hierarchy Standard ( http://www.pathname.com/fhs/ ) . For his 1.6 GByte disk, he chose these partitions: o 30 MBytes for the root directory (/) o 450 MBytes for /usr o 50 MBytes for swap space o 1000 MBytes for home directories (some of this could be used for /usr/local/) o 0 MBytes for /tmp; make /tmp a symbolic link to /var/tmp o 40 MBytes for /var It is possible to use a swap file instead of a swap partition. However this usually is a bad solution, so we suggest to use a swap partition. 3.5. Are very large disks supported? There is an upper limit on the size of the disk partition that is used for booting. This limit applies to all operating systems, not just Linux. Basically, the BIOSs typically available on PCs cannot access disk partitions larger than 1024 cylinders or tracks. Thus, any operating system used on a PC cannot be booted from a disk partition larger than 1 GByte. It is worth emphasizing that this restriction only applies to the partition from which Linux is booted. Other partitions can be larger. One solution to this limitation is to place the directory /boot/ (and usually the whole root partition) in its own (very small) partition, entirely within the first 1024 blocks of the disk. Support for large non-bootable partitions varies with the driver. Detailed information is provided in the Large-Disk mini-HOWTO. The Linux kernel includes the Multi-Device disk driver ('md'), which provides plain concatenation of drives (called linear mode) or striping support (also known as RAID 0) in software. 3.6. (How) Does Debian provide PCMCIA support? Utilities that provide PCMCIA card services have been developed by David Hinds. These utilities are provided in Debian by the package pcmcia-cs-KKK_VVV-RRR.deb, where the components 'VVV' and 'RRR' follow the usual conventions on Debian package names (6.3), and the component 'KKK' refers to the kernel version for which the pcmcia-cs package was built. The pcmcia-modules-KKK package must be rebuilt for systems not using the default Debian kernel. The pcmcia-source_VVV-RRR.deb package is provided for users who need to recompile the PCMCIA modules or utilities. It unpacks the source files for the PCMCIA utilities into the /usr/src/modules/pcmcia-cs/ directory. See the /usr/src/modules/pcmcia-cs/README.gz file; it contains instructions for rebuilding the PCMCIA packages. PCMCIA cards that include IDE drives have to be supported by the kernel. The version of the kernel distributed with the Debian installation disks includes support for such PCMCIA cards. That is, its .config file includes the line: CONFIG_BLK_DEV_IDE_PCMCIA=y. 4. Compatibility issues 4.1. How compatible is Debian with other distributions of Linux? Debian developers communicate with other Linux distribution creators in an effort to maintain binary compatibility across Linux distributions. Most commercial Linux products run as well under Debian as they do on the system upon which they were built. Debian GNU/Linux adheres strictly to the Linux File System Structure ( http://www.pathname.com/fhs/ ) (now known as the FHS). However, there is room for interpretation in some of the rules within this standard, so there may be differences between a Debian system and other Linux systems. 4.2. How source code compatible is Debian with other Unix systems? For most applications Linux source code is compatible with other Unix systems. It supports almost everything that is available in System V Unix systems and the free and commercial BSD- derived systems. However in the Unix business such claim has nearly no value because there is no way to prove it. In the software development area complete compatibility is required instead of compatibility in about most cases. So years ago the need for standards arose, and nowadays POSIX.1 (IEEE Standard 1003.1-1990) is one of the major standards for source code compatibility in Unix-like operating systems. Linux is intended to adhere to POSIX.1, but the POSIX standards cost real money and the POSIX.1 (and FIPS 151-2) certification is quite expensive; this made it more difficult for the Linux developers to work on complete POSIX conformance. The certification costs make it unlikely that Debian will get an official conformance certification even if it completely passed the validation suite. (The validation suite is now freely available, so it is expected that more people will work on POSIX.1 issues.) Unifix GmbH (Braunschweig, Germany) developed a Linux system that has been certified to conform to FIPS 151-2 (a superset of POSIX.1). This technology is available in Unifix' own distribution called Unifix Linux 2.0 and in Lasermoon's Linux-FT ( http://www.lasermoon.co.uk/linux-ft/linux-ft.html ) . Currently Unifix merges its patches into the Linux kernel, gcc and other tools; so it is expected that their fixes towards POSIX.1 conformance will be available in Debian (and other distributions). 4.3. Can I use Debian packages (.deb files) on my RedHat/Slackware/... Linux system? Can I use RedHat packages (.rpm files) on my Debian GNU/Linux system? Different Linux distributions use different package formats and different package management programs. You probably can: A program to unpack a Debian package onto a Linux host that is been built from a `foreign' distribution is available, and will generally work, in the sense that files will be unpacked. The converse is probably also true, that is, a program to unpack a RedHat or Slackware package on a host that is based on Debian Linux will probably succeed in unpacking the package and placing most files in their intended directories. This is largely a consequence of the existence (and broad adherence to) the Linux File System Standard. You probably do not want to: Most package managers write administrative files when they are used to unpack an archive. These administrative files are generally not standardized. Therefore, the effect of unpacking a Debian package on a `foreign' host will have unpredictable (certainly not useful) effects on the package manager on that system. Likewise, utilities from other distributions might succeed in unpacking their archives on Debian systems, but will probably cause the Debian package management system to fail when the time comes to upgrade or remove some packages, or even simply to report exactly what packages are present on a system. A better way: The Linux File System Standard (and therefore Debian GNU/Linux) requires that subdirectories under /usr/local/ be entirely under the user's discretion. Therefore, users can unpack `foreign' packages into this directory, and then manage their configuration, upgrade and removal individually. 4.4. Is Debian able to run my old a.out programs? To execute a program whose binary is in a.out (i.e., QMAGIC or ZMAGIC) format, o Make sure your kernel has a.out support built into it, either directly (CONFIG_BINFMT_AOUT=y) or as a module (CONFIG_BINFMT_AOUT=m). (Debian's kernel-image package contains the module binfmt_aout.) If your kernel supports a.out binaries by a module, then be sure that the binfmt_aout module is loaded. You can do this at boot time by entering the line binfmt_aout into the file /etc/modules. You can do it from the command line by executing the command insmod DIRNAME/binfmt_aout.o where DIRNAME is the name of the directory where the modules that have been built for the version of the kernel now running are stored. On a system with the 2.0.27 version of the kernel, DIRNAME is likely to be /lib/modules/2.0.27/fs/. o install the package libc4. o If the program you want to execute is an a.out X client, then install the xcompat package. If you have a commercial application in a.out format, now would be a good time to ask them to send you an ELF upgrade. 4.5. Can Debian be used to compile a.out programs? To compile programs in the a.out binary format, o install the Debian a.out developer's packages, which are - libc4-dev - aout-binutils - aout-librl - aout-gcc o place the a.out tools ahead of the ELF tools in your path. That is, execute the command export PATH=/usr/i486-linuxaout/bin:$PATH (This is not essential, just advantageous.) If you are only going to do this once, you could execute: PATH=/usr/i486-linuxaout/bin:$PATH make target. 4.6. How should I install a non-Debian package? Files under the directory /usr/local/ are not under the control of the Debian package management system. Therefore, it is good practice to place the source code for your program in /usr/local/src/. For example, you might extract the files for a package named foo.tar into the directory /usr/local/src/foo. After you compile them, place the binaries in /usr/local/bin/, the libraries in /usr/local/lib/, and the configuration files in /usr/local/etc/. If your programs and/or files really must be placed in some other directory, you could still store them in /usr/local/, and build the appropriate symbolic links from the required location to its location in /usr/local/, e.g., you could make the link ln -s /usr/local/bin/foo /usr/bin/foo In any case, if you obtain a package whose copyright allows redistribution, you should consider making a Debian package of it, and uploading it for the Debian system. Guidelines for becoming a package developer are included in the Debian policy manual (12.1). 4.7. Why can't I compile programs that require libtermcap? Debian uses the terminfo database and the ncurses library of terminal interface routes, rather than the termcap database and the termcap library. Users who are compiling programs that require some knowledge of the terminal interface should replace references to libtermcap with references to libncurses. To support binaries that have already been linked with the termcap library, and for which you do not have the source, Debian provides a package called termcap-compat. This provides both libtermcap.so.2 and /etc/termcap. Install this package if the program fails to run with the error message can't load library 'libtermcap.so.2', or complains about a missing /etc/termcap file. 4.8. Why can't I install AccelX? AccelX uses the termcap library for installation. See about termcap (4.7) above. 4.9. Why do I get Can't find libX11.so.6 errors when I try to run foo? This error message could mean that the program is in a.out format. In this case you need to install the xcompat package. 4.10. Can I install and compile a kernel without some Debian-specific tweaking? Yes. But you have to understand the Debian policy with respect to headers. The Debian C libraries are built with the most recent stable releases of the gcc headers. For example, the Debian-1.2 release used version 5.4.13 of the headers. This practice contrasts with the Linux kernel source packages distributed at all Linux FTP archive sites, which uses even more recent versions of the headers. The kernel headers distributed with the kernel source are located in /usr/include/linux/include/. If you need to compile a program with kernel headers that are newer than those provided by libc5-dev, then you must add -I/usr/src/linux/include/ to your command line when compiling. This came up at one point, for example, with the packaging of the automounter daemon (amd). When new kernels changed some internals dealing with NFS, amd needed to know about them. This required the inclusion of the latest kernel headers. 5. Software available in the Debian system 5.1. What types of applications and development software are available for Debian GNU/Linux? Like most Linux distributions, Debian GNU/Linux provides: o the major GNU applications for software development, file manipulation, and text processing, including gcc, libc, g++, make, texinfo, gnuplot, the Bash shell and numerous upgraded Unix utilities, o Perl and its libraries, o TeX, LaTeX, and dvips, o the X Window System, which provides a networked graphical user interface for Linux, and numerous X applications, o a full suite of other networking applications, including WWW servers, browsers, and development tools. Nearly 700 packages, ranging from news servers and readers to sound support, FAX programs, database and spreadsheet programs, image processing programs, communications, net, and mail utilities, Web servers, and even ham-radio programs are included in the distribution. Another 50 software suites are available as Debian packages, but are not formally part of Debian due to license restrictions. 5.2. Who wrote all that software? o For each package the authors of this program are credited in thefile /usr/doc/PACKAGE/copyright, where PACKAGE is to be substituted with the package's name. (Packages conforming to an older Debian Packaging Standard have this in the file /usr/doc/copyright/PACKAGE instead.) o Maintainers who package this software for the Debian Linux system are listed in the Debian control file (6.4) that comes with each package. 5.3. How can I get a current list of programs that have been packaged for the Debian project? A complete list is available from any of the Debian mirrors. The file indices/Packages-Master-i386.gz provides a list, including short descriptions, of all packages that are available for computers with 80386 (or more advanced) chips. The file indices/Packages-Master-m68k.gz provides a similar list of packages that are available for computers with Motorola 68k0x0 CPUs. The WWW interface to the Debian packages conveniently summarizes the packages in each of about twenty sections of the Debian archive, as well as the 10 most recently uploaded packages. 5.4. What is missing from Debian GNU/Linux? A list of packages which are most urgently needed for Debian is maintained by Sven Rudolph. For more details, see the section on contributing to the Debian project (14.1). 5.5. Where is 'which'? This is a historical question, no longer relevant, but is included with this FAQ because it may still hold the record as the single most frequently asked question on the Debian mailing lists. The functionality of the Berkeley utility which is provided in the Bash shell by the built-in command type. To learn the path name for an executable file foo, use the command type foo. To learn all the paths where foo can be found, use type -a foo. To accommodate users' lack of familiarity with this (in this writer's opinion, obscure) feature of Bash, the Debian maintainers have built a package called debianutils, which includes a Bash script called which. This script includes only these lines: #!/bin/bash for i in $*; do type -all -path $i | head -1 done The debianutils package is normally stored in the base section of the FTP archive, and is therefore part of the initial installation of every Debian system. 5.6. (How) Does Debian support Java? The Java Development Kit from Sun is currently available as a Debian package (jdk_VVV-RRR.deb). The JDK will allow you to run Java programs and applets, and write your own. If your kernel is properly configured (see below), the JDK will allow you to run Java programs just like other executables. The JDK package also includes a number of demo programs. Debian's kernel is configured with Java support built in as a module (i.e., CONFIG_BINFMT_JAVA=m). Users who wish to build their own custom kernel (10.1) can of course omit this if they choose. Once module support is available in the kernel, you need to make sure the module is loaded. You can do it at boot time by inserting the line binfmt_java in the file /etc/modules. Alternatively, you can install the module from the command line by executing the command insmod DIRNAME/binfmt_java.o where DIRNAME is the name of the directory where the modules that have been built for the version of the kernel now running are stored. On a system with the 2.0.0 version of the kernel, DIRNAME is likely to be /lib/modules/2.0.0/fs/. You can check that a module is loaded using the command lsmod. Running a Java applet requires a browser with the capability to recognize and execute them. The Netscape browser that can be installed as a Debian package will run Java applets. (The Netscape source code is not publicly available. The Debian netscape package provides a wrapper which aids the installation and management of Netscape on a Debian system. This is actually a good example of the integration of commercial packages with the Debian system.) A final note of mixed blessings: Sun's licensing policies on the JDK are becoming more restricted with time, so this package may not be available as part of Debian soon. It is possible that it may be available in the same way that Netscape is available for Debian Linux. Better news is that a number of programs are currently being developed with may provide attractive publicly-available alternatives. 5.7. What are all those directories (stable/development/non-free/contrib/project) at the Debian FTP archives? The software that has been packaged for Debian GNU/Linux is available in one of several directory trees on each Debian mirror site. 5.7.1 Top-level Directories The Major Package Trees: o Debian-1.2: This directory contains the packages which formally constitute the most recent release of the Debian Linux system. The contents of this directory do not change. o Debian-1.2-updates: Updates to the current release are in this directory. o Debian-1.2.x, a.k.a. stable: A copy of the current release with the updates applied. The minor number is changed whenever new updates are added. o non-free: This directory contains packages whose distribution is restricted in a way which requires that distributors take careful account of the specified copyright requirements. For example, some packages have licenses which prohibit commercial distribution. Others can be redistributed but are in fact shareware and not freeware. The licenses of each of these packages must be studied, and possibly negotiated, before the packages are included in any redistribution (e.g., in a CD-ROM). o contrib: This directory contains packages which are freely distributable, but do not meet the policy requirements for distribution by the Debian project for some reason, e.g., the packages have some unusual restriction on modification by other users, or are only available in binary form. For such packages, the project cannot given the user any means to assure that they are free of Trojan horses, and cannot port them to other architectures. Binary-only packages which are not freely redistributable are placed in the non-free directory. Supplementary directories: o tools: DOS utilities for creating boot disks, partitioning your disk drive, compressing/decompressing files, and booting Linux. o upgrades: Files needed for upgrading a debian-0.93 system (based on a.out binary format files) to Debian-1.1 (or later, based on ELF binary files). Included are instructions for upgrading (either manually using dpkg, or more automatically, using dselect), along with a copy of the particular version of the package management tool, dpkg that must be used in a.out systems to start the upgrade, and a list of files that will be needed in order to do the upgrade. o doc: Documentation, instructions on how to submit bug reports. o debian-lists: Archives of the Debian mailing lists. Of particular interest to developers: o development: A snapshot of the current development system. Users are welcome to use and test these packages, but are warned about their state of readiness. o project/experimental/: This directory contains packages and tools which are being developed specifically for the Debian project, and are still in the testing stage. Users are welcome to use and test these packages, but warned about their state of readiness. o private/project/Incoming/: Packages that have been uploaded by developers, and which are awaiting placement in the directory hierarchy by the distribution maintainer. o indices/: Various lists, including the Packages-Master file. 5.7.2 Sub-directories Within each of the major directory trees (stable, non-free, contrib, and development, but not project/experimental), which is too small to subdivide), the binary packages reside in sub-directories whose names indicate the chip architecture for which they were compiled: o binary, which is normally a link to binary-i386. o binary-all, for packages which are architecture-independent. These include, for example, Perl scripts. o binary-i386, for packages which execute on 80x86 machines. o binary-m68k, for packages which execute on machines based on one of the Motorola 680x0 processors. Currently this is done mainly for Atari and Amiga computers, and also for some VME based industry standard boards. There is no port of Linux to the old m68k based Macintoshes, because Apple did not supply the needed hardware information. o binary-sparc, for packages which execute on Sun Sparcstations. o binary-alpha, for packages which execute on DEC Alpha machines. 5.8. Is source code included with the system? Source code is included for everything in the Debian system. Most of the license terms of programs in the system require that source code be distributed along with the programs, or that an offer to provide the source code accompany the programs. Source code may or may not be available for packages in the contrib and non-free directories, which are not formally part of the Debian system. 5.9. How can I check that I am using a Debian system? The existence of the program dpkg shows that you should be able to install Debian packages on your system. In order to make sure that your system has been installed from the real Debian base disks check for the existence of /etc/debian_version. 5.10. How can I tell what version of the Debian system I am using? There is a file, /etc/debian_version, which contains a single one-line entry giving the version number of the release, as defined by the package base. Users should be aware, however, that the Debian system consists of many parts, each of which can be updated (almost) independently. Each Debian release contains well defined and unchanging contents. Updates are separately available. For a one-line description of the installation status of package foo, use the command dpkg --list foo. (With no arguments, this command prints out versions of all installed packages.) For a more verbose description, use dpkg --status foo. 5.11. How does Debian support non-English languages? o Debian GNU/Linux is distributed with keymaps for nearly two dozen keyboards, and with utilities (in the kbd package) to install, view, and modify the tables. The installation prompts the user to specify the keyboard he will use. o Support for French-, German-, Italian- and Spanish-language manual pages is provided through the manpages-fr, manpages-de, manpages-it and manpages-es packages. To access an NLS manual page, the user must set LC_MESSAGES to the appropriate string. In the case of the German-language manual pages, LC_MESSAGES must be set to 'de_DE'. The man program will then search for German manual pages under /usr/man/de_DE/. 5.12. What about the US export regulation limitations? US laws place restrictions on the export of defense articles, which includes some types of cryptographic software. PGP and ssh fall into this category. To prevent anyone from taking unnecessary legal risks, certain Debian GNU/Linux packages are only available from a non-US site ( ftp://os.inf.tu-dresden.de:/pub/debian-non-US/ ) , there is a list of mirror sites ( ftp://os.inf.tu-dresden.de/pub/debian-non-US/README.mirrors ) 6. Basics of the Debian Package Management System 6.1. What is a Debian package? Packages generally contain all of the files necessary to implement a set of related commands or features. There are two types of Debian packages: o Binary packages, which contain executables, configuration files, man/info pages, copyright information, and other documentation. These packages are distributed in a Debian-specific archive format (6.2); they are usually distinguished by having a '.deb' file extension. Binary packages can be unpacked using the Debian utility dpkg; details are given in its manual page. o Source packages, which consist of a .dsc file describing the source package (including the names of the following files), a .orig.tar.gz file that contains the original unmodified source in gzip-compressed tar format and usually a .diff.gz file that contains the Debian-specific changes to the original source. The utility dpkg-source packs and unpacks Debian source archives; details are provided in its manual page. Installation of software by the package system uses dependencies which are carefully designed by the package maintainers. These dependencies are documented in the control file associated with each package. For example, the package containing the GNU C compiler (gcc) depends on the package binutils which includes the linker and assembler. If a user attempts to install gcc without having first installed binutils, Debian's package system will send an error message that it also needs binutils, and will install gcc only if the user agrees to install binutils first. (However, this facility can be overridden by the insistent user.) See more details on package dependencies (6.9) below. Debian's packaging tools can be used to: o manipulate and manage packages or parts of packages, o aid the user in the break-up of packages that must be transmitted through a limited-size medium such as floppy disks, o aid developers in the construction of package archives, and o aid users in the installation of packages which reside on a remote FTP site. 6.2. What is the format of a Debian binary package? A Debian package, or a Debian archive file, contains the executable files, libraries, and documentation associated with a particular suite of program or set of related programs. Normally, a Debian archive file has a filename that ends in .deb. The internals of this Debian binary packages format are described in the deb(5) manual page. This internal format is subject to change, therefore always use dpkg-deb(8) for manipulating .deb files. 6.3. Why are Debian package file names so long? The Debian binary package file names conform to the following convention: foo_VersionNumber-DebianRevisionNumber.deb Note that foo is supposed to be the package name. As a check, one can learn the package name associated with a particular Debian archive file (.deb file) in one of these ways: o inspect the Packages file in the directory where it was stored in a Debian FTP archive site. This file contains a stanza describing each package; the first field in each stanza is the formal Package Name. o use the command dpkg --info foo_VVV-RRR.deb. This sends a message to STDOUT which gives, among other things, the Package Name corresponding to the archive file being unpacked. The VVV component is the version number specified by the upstream developer. There are no standards in place here, so the version number may have formats as different as 960428 and 2.7.2.l.3. The RRR component is the Debian revision number, and is specified by the Debian developer (or an individual user if he chooses to build the package himself). This number corresponds to the revision level of the Debian package (which includes the Debian-specific Makefile, called debian/rules, as well as the Debian control file, usually called debian/control). Thus, a new revision level usually signifies changes in the Debian Makefile, the Debian control file, the installation or removal scripts, or in the configuration files used with the package. 6.4. What is a Debian control file? Specifics regarding the contents of a Debian control file are provided in the dpkg programmer's manual ( ftp://ftp.debian.org/debian/doc/package-developer/programmer.ps.gz ) . Briefly, a sample control file is shown below for the Debian package hello: Package: hello Version: 1.3-13 Architecture: i386 Depends: libc5 (>= 5.2.18) Installed-Size: 31 Maintainer: Ian Jackson Description: The classic greeting, and a good example The GNU hello program produces a familiar, friendly greeting. It allows nonprogrammers to use a classic computer science tool which would otherwise be unavailable to them. . Seriously, though: this is an example of how to do a Debian package. It is the Debian version of the GNU Project's `hello world' program (which is itself an example for the GNU Project). The Package field gives the package name. This is the name by which the package can be manipulated by the package tools, and usually similar to but not necessarily the same as the first component string in the Debian archive file name. The version field gives both the upstream developer's version number and (in the last component) the revision level of the Debian package of this program as explained in (6.3). The Architecture field specifies the chip for which this particular binary was compiled. The Depends field gives a list of packages that have to be installed in order to install this package successfully. The Installed-Size indicates how much disk space the installed package will consume. This is intended to be used by installation front-ends in order to show whether there is enough disk space available to install the program . The Maintainer field gives the e-mail address of the person who is currently responsible for maintaining this package. The Description field gives a brief summary of the package's features. 6.5. What is a Debian conffile? Conffiles are listings of configuration files, usually placed in /etc, that the package management system will not overwrite when a package is upgraded. This ensures that local values for the contents of these files will be preserved, and is a critical feature enabling the in-place upgrade of packages on a running system. To determine exactly which files are preserved during an upgrade, run dpkg --status package. 6.6. What is a Debian preinst, postinst, prerm, and postrm script? These files are executable scripts which are automatically run before or after a package is installed. Along with a file named control, all of these files are part of the control section of a Debian archive file. The individual files are: preinst This script executes before that package will be unpacked from its Debian archive (.deb) file. Many 'preinst' scripts stop services for packages which are being upgraded until their installation or upgrade is completed (following the successful execution of the 'postinst' script). postinst This script typically completes any required configuration of the package foo once foo has been unpacked from its Debian archive (.deb) file. Often, 'postinst' scripts ask the user for input, and/or warn the user that if he accepts default values, he should remember to go back and re-configure that package as the situation warrants. Many 'postinst' scripts then execute any commands necessary to start or restart a service once a new package has been installed or upgraded. It is a good idea to check the contents of the 'postinst' script for any configuration advice, when trying out a package for the first time. prerm This script typically stops any daemons which are associated with a package. It is executed before the removal of files associated with the package. postrm This script typically modifies links or other files associated with foo. (See notes on Virtual packages (6.8).) Currently all of the control files can be found in /var/lib/dpkg/info. The files relevant to package foo begin with the name foo and have file extensions of preinst, postinst, etc., as appropriate. The file foo.list in that directory lists all of the files that were installed with the package foo. (Note that the location of these files is a dpkg internal; you should not rely on it.) 6.7. What is a Required/Important/Standard/Optional/Extra package? Each Debian package is assigned a priority by the distribution maintainers, as an aid to the package management system. The priorities are: o Required packages are necessary for the proper functioning of the system. This inludes all tools that are necessary to repair system defects. You must not remove these packages or your system may become totally broken and you may probably not even be able to use dpkg to put things back. Systems with only the Required packages are probably unusable, but they do have enough functionality to allow the sysadmin to boot and install more software. o Important packages should be found on any Unix-like system. Other packages which the system will not run well or be usable without will be here. This does NOT include Emacs or X11 or TeX or any other large applications. These packages only constitute the bare infrastructure. o Standard packages are standard on any Linux system, including a reasonably small but not too limited character-mode system. This is what will install by default if users do not select anything else. It does not include many large applications, but it does include Emacs (this is more of a piece of infrastructure than an application) and a reasonable subset of TeX and LaTeX (if this turns out to be possible without X). o Optional packages include all those that you might reasonably want to install if you did not know what it was or do not have specialized requirements. This includes X11, a full TeX distribution, and lots of applications. o Extra packages conflict with others with higher priorities, or are only likely to be useful if you already know what they are or have specialized requirements. 6.8. What is a Virtual Package? A virtual package is a generic name that applies to any one of a group of packages, all of which provide similar basic functionality. For example, both the tin and trn programs are both news readers, and should therefore satisfy any dependency of a program that required a news reader on a system in order to work or to be useful. They are therefore both said to provide the virtual package called news-reader. Similarly, smail and sendmail both provide the functionality of a mail transport agent. They are therefore said to provide the virtual package, mail transport agent. If either one is installed, then any program depending on the installation of a mail-transport-agent will be satisfied by the existence of this virtual package. Debian provides a mechanism so that, if more than one package which provide the same virtual package is installed on a system, then system administrators can set one as the preferred package. The relevant command is update-alternatives, and is described further in the section on diversions (11.8). 6.9. What is meant by saying that a file Depends/Recommends/Suggests/Conflicts/Replaces/Provides another package ? The Debian package system has a range of package dependencies which are designed to indicate (in a single flag) the level at which Program A can operate independently of the existence of Program B on a given system: o Package A depends on Package B if B absolutely must be installed in order to run A. In some cases, A depends not only on B, but on a version of B. In this case, the version dependency is usually a lower limit, in the sense that A depends on any version of B more recent than some specified version. o Package A recommends Package B, if the package maintainer judges that most users would not want A without also having the functionality provided by B. o Package A suggests Package B if B contains files that are related to (and usually enhance) the functionality of A. o Package A conflicts with Package B when A will not operate if B is installed on the system. Most often, conflicts are cases where A contains files which are an improvement over those in B. Conflicts are often combined with replaces. o Package A replaces Package B when files installed by B are removed and (in some cases) over-written by files in A. o Package A provides Package B when all of the files and functionality of B are incorporated into A. This mechanism provides a way for users with constrained disk space to get only that part of package A which they really need. More detailed information on the use of these terms can be found in the Debian programmer's manual. 6.10. What is meant by Pre-Depends? Pre-Depends is a special dependency. In the case of most packages, dpkg will unpack its archive file (i.e., its .deb file) independently of whether or not the files on which it depends exist on the system. Simplistically, unpacking means that dpkg will extract the files from the archive file that were meant to be installed on your filesystem, and put them in place. If those packages depend on the existence of some other packages on your system, dpkg will refuse to complete the installation by executing its configure action until the other packages are installed. However, for some packages, dpkg will refuse even to unpack them until certain dependencies are resolved. Such packages are said to Pre-depend on the presence of some other packages. The Debian project provided this mechanism to support the safe upgrading of systems from a.out format to ELF format, where the order in which packages were unpacked was critical. More detailed information on the use of these terms can be found in the Debian programmer's manual. 6.11. What is meant by unknown/install/remove/purge/hold in the package status? These want flags tell what the user wanted to do with a package (as indicated either by the user's actions in the Select section of dselect, or by the user's direct invocations of dpkg). Their meanings are: o unknown - the user has not said whether he wants the package o install - the user wants the package installed or upgraded o remove - the user wants the package removed, but does not want to remove any existing configuration files. o purge - the user wants the package to be removed completely, including configuration files. o hold - the user wants this package not to be processed, i.e., he wants to keep the current version with the current status whatever that is. 6.12. Where will I get detailed info on creating Debian packages? See the dpkg programmer's manual and the Debian policy manual (12.1) 7. The Debian Package Management Tools 7.1. What program(s) does Debian provide for managing its packages? 7.1.1 dselect This program is a menu-driven interface to the Debian package management system. It is particularly useful for first-time installations and large-scale upgrades. dselect can o guide the user as he/she chooses among packages to install or remove, ensuring that no packages are installed that conflict with one another, and that all packages required to make each package work properly are installed; o warn the user about inconsistencies or incompatibilities in their selections; o determine the order in which the packages must be installed; o automatically perform the installation or removal; and o guide the user through whatever configuration process are required for each package. dselect begins by presenting the user with a menu of 7 items, each of which is a specific action. The user can select one of the actions by using the arrow keys to move the highlighter bar, then pressing the ENTER key to select the highlighted action. What the user sees next depends on the action he selected. If he selects any option but Access or Select, then dselect will simply proceed to execute the specified action: e.g., if the user selected the action Remove, then dselect would proceed to remove all of the files selected for removal when the user last chose the Select action. Both the Access menu item and the Select menu item lead to additional menus. In both cases, the menus are presented as split screens; the top screen gives a scrollable list of choices, while the bottom screen gives a brief explanation (info) for each choice. Extensive on-line help is available: Use the '?' key to get to a help screen, then use the '.' key to see each of the several pages of help one screen at a time. Some users find it easier to navigate dselect when it is colorized. To see color screens in dselect, be sure that you have executed: export TERM=linux before invoking dselect. The order in which the actions are presented in the first dselect menu represents the order in which a user would normally choose dselect to install packages. However, a user can pick any of the main menu choices as often as needed (including not at all, depending on what one wants to do). o Begin by choosing an Access Method. This is the method by which the user plans on accessing Debian packages; e.g., some users have Debian packages available on CD-ROM, while others plan to fetch them using anonymous ftp. The selected Access Method is stored after dselect exits, so if it does not change, then this option need not be invoked again. o Then Update the list of available packages. To do this, dselect reads the file Packages.gz which should be included in the top level of the directory where the Debian packages to be installed are stored. (But if it is not there, dselect will offer to make it for you.) o Select specific packages for installation on his system. After choosing this menu item, the user is first presented with a full screen of help; he can exit it (and any help screen) by pressing the SPACEBAR. Better (for first time users) is to read all of the help screen, but repeatedly pressing the '.' key to fetch one page of help after another. Once the user exits the Help screen, he sees the split-screen menu for choosing packages to install (or remove). The top screen is a relatively narrow window into the list of Debian's nearly 700 packages; the bottom screen is a window into info about the package or group of packages which are highlighted in the top. First-time users are often confused by these aspects of the Select screen: - Deselecting a packages: One can specify which packages should be removed (previously called deselecting an item) by highlighting a package name or the label for a group of packages (e.g., All) and then pressing either: * the '-' key. This removes most of the files associated with the package, but preserves the files listed as configuration files (6.5) and other configuration information. * the '_' key. This removes every file that is part of the package. Note that if you deselect All Packages your system will be reduced to the initial installed base packages. This is probably what you wanted. - Putting a package on hold (by pressing '='): This effectively tells dselect not to upgrade a package even if the version currently installed on your system is not as recent as the version that is available in the Debian repository you are using (this was specified when you set the Access Method). (The version that is available in the repository is given in the file Packages.gz that is read when the Update menu choice is activated.) Putting a package on unhold (by pressing ':'): This is the default, and means that the packages will be upgraded if a newer version is available. - The order in which the packages are presented: The default order is to present packages by Priority; within each priority, packages are presented in order of the directory (a.k.a. section) of the archive in which they are stored. Given this sort order, some packages in section A (say) may be presented first, followed by some packages in section B, followed by more packages (of lower priority) in section A. Users can select a different presentation order by using the 'o' key to cycle between various options for sorting the packages. - Meanings of the labels at the top of the screen: The labels at the top can be expanded by using the 'v' (verbose) key. This action pushes much of the text that formerly fit onto the display off to the right. To see it, press the right arrow; to scroll back to the left, press the left arrow. - What to do with a package conflict/dependency screen: If a user selects (for installation or removal) a package, e.g., foo.deb that depends on or recommends another package, e.g., blurf.deb, then dselect will place the user in a sub-screen of the main selection screen. This process begins by presenting the user with a full-screen Help file, which can be escaped by pressing SPACEBAR. Thereafter, the user can choose among the related packages, accepting the suggested actions (to install or not), or rejecting them. To do the latter, press SHIFT-D; to return to the former, press SHIFT-U. In any case, the user can save his selections and return to the main selection screen by pressing SHIFT-Q. o Users returning to the main menu can then select the Install menu item to unpack and configure the selected packages. Alternatively, users wishing to remove files can choose the Remove menu item. At any point, users can choose Quit to exit dselect; users' selections are preserved by dselect. 7.1.2 dpkg This is the main package management program. dpkg can be invoked with many options. Some common uses are: o Find out all the options: dpkg --help. o Print out the control file (and other information) for a specified package: dpkg --info foo_VVV-RRR.deb o Install a package (including unpacking and configuring) onto the file system of the hard disk: dpkg --install foo_VVV-RRR.deb. o Unpack (but do not configure) a Debian archive into the file system of the hard disk: dpkg --unpack foo_VVV-RRR.deb. Note that this operation does not necessarily leave the package in a usable state; some files may need further customization to run properly. This command removes any already-installed version of the program and runs the preinst (6.6) script associated with the package. o Configure a package that already has been unpacked: dpkg --configure foo. Among other things, this action runs the postinst (6.6) script associated with the package. It also updates the files listed in the conffiles for this package. Notice that the 'configure' operation takes as its argument a package name (e.g., foo), not the name of a Debian archive file (e.g., foo_VVV-RRR.deb). o Extract a single file named blurf (or a group of files named blurf* from a Debian archive: dpkg --fsys-tarfile foo_VVV-RRR.deb | tar -xf - blurf* o Remove a package (but not its configuration files): dpkg --remove foo. o Remove a package (including its configuration files): dpkg --purge foo. o List the installation status of packages containing the string foo*: dpkg --list 'foo*'. 7.1.3 dpkg-deb This program manipulates Debian archive(.deb) files. Some common uses are: o Find out all the options: dpkg-deb --help. o Determine what files are contained in a Debian archive file: dpkg-deb --contents foo_VVV-RRR.deb) o Extract the files contained in a named Debian archive into a user specified directory: dpkg-deb --extract foo_VVV-RRR.deb tmp extracts each of the files in foo_VVV-RRR.deb into the directory tmp/. This is convenient for examining the contents of a package in a localized directory, without installing the package into the root file system. More information is given in the manual page dpkg-deb(1). 7.1.4 dpkg-split This program splits large package into smaller files (e.g., for writing onto a set of floppy disks), and can also be used to merge a set of split files back into a single file. It can only be used on a Debian system, since it calls the program dpkg-deb to parse the debian package file into its component records. For example, to split a big .deb file into N parts, o Execute the command dpkg-split --split foo.deb. This will produce N files each of approximately 460 KBytes long in the current directory. o Copy those N files to floppy disks. o Copy the contents of the floppy disks onto the hard disk of your choice on the other machine. o Join those part-files together using dpkg-split --join "foo*". 7.2. Debian claims to be able to update a running program; how is this accomplished? Debian GNU/Linux provides a program called the start-stop-daemon which is used by installation scripts to start daemons at boot time or to stop daemons when the kernel runlevel is changed (e.g., from multi-user to single-user or to halt). The start-stop-daemon command is also used when a new package containing a daemon is installed, to stop running daemons, and restart them as necessary, e.g., when a package is being installed with an updated configuration script. 7.3. How can I tell what packages are already installed on a Debian system? To learn the status of all the packages installed on a Debian system, execute the command dpkg --list. This prints out a one-line summary for each package, giving a 2-letter status symbol, the package name, the version which is installed, and a very brief description. To learn the status of packages whose names match the string any pattern beginning with foo by executing the command dpkg --list 'foo*' To get a more verbose report for a particular package, execute the command: dpkg --status foo. 7.4. How can I find out what package produced a particular file? To identify the package that produced the file named foo execute either: o dpkg --search filename. This searches for filename in installed packages. (This is (currently) equivalent to searching all of the files having the file extension of .list in the directory /var/lib/dpkg/info/.) o grep foo Contents, or zgrep foo Contents.gz. This searches for files which contain the substring foo in their full path names. The files Contents and Contents.gz reside in the major package directories (stable, non-free, contrib, development) at a Debian FTP site. A Contents file refers only to the packages in the subdirectory tree where it resides. Therefore, a user might have to search more than one Contents files to find the package containing the file foo. This method has the advantage over dpkg --search in that it will find files in packages that are not currently installed on your system. 8. Getting and Installing Debian GNU/Linux 8.1. Where/how can I get the Debian installation disks? You can get the installation disks by downloading the appropriate files from the Debian FTP site: ( ftp://ftp.debian.org/debian/ ) and its mirrors ( http://www.debian.org/ftplist.html ) . From the directory stable/disks-i386/current/, you will need: The Installation Guide. This document gives detailed installation instructions. It is available in the files install.txt (ASCII) and install.html (HTML). The Rescue Disk. This disk is the boot disk and contains a minimal file system and the installation program. If your system can boot from a 1.44 MByte floppy disk drive, download the file called resq1440.bin. On the other hand, if your system can boot only from a 1.2 MByte floppy disk drive, download the file called resq1200.bin. (There seems to be no resq1200.bin file available right now.) The Device Driver Disk. This disk contains many device drivers that can be loaded into the Linux kernel. If your system has a 1.44 MByte floppy disk drive, you can use the file called drv1440.bin. On the other hand, if your system only has a 1.2 MByte floppy disk drive, you have to download the file called drv1200.bin. The Base Disks. These disks contain the software that is necessary to have a bare-bones system. If your system has a 1.44 MByte floppy disk drive, you can use the files called base14-1.bin, base14-2.bin, base14-3.bin and base14-4.bin. On the other hand, if your system only has a 1.2 MByte floppy disk drive, you have to download the files called base12-1.bin, base12-2.bin, base12-3.bin and base12-4.bin. Once you have downloaded these files, transfer them to a disk as described in the Installation Guide. You may, of course, get these disks from a friend. You can make as many copies as you want. Debian is freely redistributable, provided you follow a few simple rules. For more information, see The GNU General Public License ( http://www.gnu.ai.mit.edu/copyleft/copyleft.html ) . If you cannot get copies of the installation disks from one of the Debian FTP sites or from a friend, then make a request to one of the Debian mailing lists. See the debian-user mailing list (12.2). The likelihood is very high that someone will be willing to help. 8.2. OK, I have got the disks; how do I install the system? Complete, detailed instructions are given in the Installation Guide that you downloaded above. Follow these instructions! 8.3. How (and on what media) can I get the Debian packages? Once the base system has been installed, you can complete the installation of your Debian GNU/Linux system by accessing packages on any (or several) of these media: o a CD-ROM (8.4) containing Debian. o a remote NFS (8.5) server. o a partition of your hard disk (8.7). o a collection of floppy disks (8.6). o a remote system accessible by anonymous ftp (8.8). In each case, you can use either o dselect (7.1.1), Debian's user-interface program to its package system. (This will help you mount the device containing the Debian package files (if necessary), and then guide you through the selection of packages and their installation on your system.) Or, o use dpkg (7.1.2) directly to control the installation of individual packages. Debian gurus quizzically refer to this approach as installing packages by hand. 8.4. How do I get and install the Debian from CD-ROM? Linux supports the ISO 9660 (CD-ROM) file system with Rock Ridge extensions (formerly known as High Sierra). Several vendors provide Debian in this format; these vendors have directly supported the Debian project: o iConnect Corp.: i-Connect.Net provides the master FTP system used by Debian developers, and its network connection and system administration. They provide our 168 developers with free accounts on a system that is exclusively for our use, and they run our DNS domain. They also maintain several Debian packages. Use the following contact info to order their CD-ROM: - WWW: ( http://www.i-connect.net/i-connect/services/cdrom.html ) - E-Mail (sales): sales@i-connect.net - E-Mail (help): help@i-connect.net - Phone from inside the US: 1-503-641-8774 - Phone from outside the US: +1-503-641-8774 - Postal address: iConnect Corp. 14355 SW Allen Blvd., Suite 140 Beaverton, OR 97005 o Flexible Software: This company maintains 8 Debian packages, and puts a lot of manpower into supporting users on the debian-user mailing list and refining the system design with our developers. They have carefully documented the development of one of the two methods used to upgrade from Debian 0.93 to Debian 1.1. - E-Mail (sales): dwarf@polaris.net - Postal address: Flexible Software 1000 McCrackin Road Tallahassee, FL 32308 To install packages provided on a CD-ROM, you must have CD-ROM support built into the kernel you use. This may require a a custom modification of the file /etc/conf.modules, or (unlikely nowadays) a special argument on the boot command line. To mount a CD-ROM under the mount point /cdrom/ (a directory which should have been created during installation), use these commands: o mount -t iso9660 /dev/hdd /cdrom/ if the CD-ROM is an IDE drive on the secondary IDE controller, or o mount -t iso9660 /dev/scd0 /cdrom/ if the CD-ROM is a SCSI drive, or o mount -t iso9660 /dev/xxxxx /cdrom/ where xxxxx refers to CD-ROMs which are sbpcd, cdu31a, or some other proprietary (non-IDE) drive. 8.5. How do I get and install Debian from an NFS-mounted drive? Debian packages on remote hosts can be installed via the Network File System using a SLIP, PPP, PLIP or Ethernet connection. SLIP and PPP require the netbase and netstd packages to be installed first. These packages are not part of the Debian base system, and must be obtained by one of the other methods described in this section. No special kernel configuration (other than the network drivers for SLIP, PPP, PLIP, or one of the Ethernet cards) is necessary to access a remote filesystem using NFS. As with all network communication, the appropriate ifconfig and route commands will have to be issued before accessing a remote disk using NFS. To mount a network-accessible file system using NFS (say, /var/spool/debian/) under the local directory /usr/local/debian/, issue the command o mount -t nfs host.fully-qualified.domain.name:/var/spool/debian/ -o ro,nosuid,soft /usr/local/debian/ To ensure that the filesystem is always accessible, the appropriate string could be added to /etc/fstab: o rulway.leidenuniv.nl:/var/spool/ftp.pub.linux.debian/ /mnt/debian/ nfs ro,nosuid,soft The preceding example shows the appropriate entry for the NFS site at Leiden University, the Netherlands. See README.mirror ( ftp://ftp.debian.org/debian/README.mirror ) for other sites providing NFS access to their Debian mirror. 8.6. How can I get/install the Debian from a set of floppy disks? Copy the Debian packages onto formatted floppy disks. Either a DOS, the native Linux ext2, or the minix format will do; one just has to use a mount command appropriate to the floppy being used. Using floppy disks has these complications: o Short MS-DOS filenames: If you are trying to place Debian package files onto MS-DOS formatted disks, you will find that their names are generally too long, and do not conform to the MS-DOS 8.3 filename limitation. To overcome this, Debian developers make all of their packages available by 8.3 filenames in separate msdos subdirectories ( stable/msdos-i386/, non-free/msdos-i386/, contrib/msdos-i386/, and development/msdos-i386/). The files in these subdirectories are merely symbolic links to the Debian archive files; they only differ from the files in the binary-i386/, etc. directories by having shorter file names. o Large file sizes: Some packages are larger than 1.44 MBytes, and will not fit onto a single floppy disk. To solve this problem, use the dpkg-split (7.1.4) tool, available in the tools directory at ( ftp://ftp.debian.org/debian/ ) and its mirrors ( http://www.debian.org/ftplist.html ) . You must have support in the kernel for floppy disks in order to read and write to floppy disk; most kernels come with floppy drive support included in them. To mount a floppy disk under the mount point /floppy (a directory which should have been created during installation), use: o mount -t msdos /dev/fd0 /floppy/ if the floppy disk is in drive A: and has an MS-DOS filesystem, o mount -t msdos /dev/fd1 /floppy/ if the floppy disk is in drive B: and has an MS-DOS filesystem, o mount -t ext2 /dev/fd0 /floppy/ if the floppy disk is in drive A: and has an ext2 (i.e., a normal Linux) filesystem. 8.7. How can I get/install the Debian from my own hard disk? The Debian packages can be installed from a hard disk on your system, either IDE, EIDE, SCSI (including Jaz drives), or a drive connected through a parallel port. Kernel support must of course be available for the type of drive you have. The appropriate drivers are: o CONFIG_BLK_DEV_IDE for IDE or EIDE drives; most kernels include this driver. o CONFIG_SCSI for SCSI drives (including Jaz drives), along with one of the (many) drivers for your particular SCSI interface. o CONFIG_SCSI_PPA for the parallel port version of ZIP drives. To start the installation invoke the program dselect, select the hard disk access method and follow the instructions. This will ask you for the device name where Debian resides. These device names are constructed as follows: (below X is to be substituted by the partition number (X =1,2,3, or 4)) o /dev/hdaX if the disk is drive C: and has an MS-DOS filesystem, o /dev/sdaX if the disk is a SCSI drive and has the lowest SCSI ID of any SCSI device on your system, o /dev/sdbX if the disk is a SCSI drive and has the second lowest SCSI ID of any SCSI device on your system o /dev/ppa0 if the disk is a Zip drive. Note that files on a disk partition having an MS-DOS filesystem must conform to the DOS filename limitation of 8 characters plus a 3 character extension. Files in the stable/msdos-i386/, non-free/msdos-i386/, contrib/msdos-i386/, and development/msdos-i386/ directories conform to this limitation. 8.8. How can I get and install Debian directly from a remote ftp site? Install the Debian tool dpkg-ftp (9.2). This package is currently installed in the directory development/binary-all/net at ( ftp://ftp.debian.org/debian/ ) and its mirrors ( http://www.debian.org/ftplist.html ) . For details on installing a package, see notes on dpkg (7.1.2). Then invoke the program dselect, which will call dpkg-ftp for you, guide you through the selection of packages, then install the packages, without every downloading the packages themselves to your machine. This method is designed to save the user both disk space and time. Note that no special kernel configuration is needed to access and install Debian packages by this method. To use this service of dselect, you will need to know: o the fully qualified domain name of the anonymous ftp site you plan to use. o the directory which contains the files you want to install, or the subdirectories which contain files you want to install. This directory must contain a file called Packages (or its compressed equivalent, Packages.gz). 8.9. How can I get and install Debian from a tape? At present, installing packages directly from tape is not supported. One can however, use tar, cpio, or afio to copy Debian archive files onto a tape, then copy them onto your local disk for installation. In the same vein, floppy disks containing tar files would have to be copied onto a local disk before they could be managed with the Debian package tools. 8.10. What is the latest version of Debian? Currently there are three versions of Debian: o 1.2: this is stable software, and will not change. o 1.2.x, a.k.a. stable, a.k.a ; this is stable software, but it may change when major fixes are incorporated. o the development version; this is the version currently under development; it is updated continuously. You can retrieve packages from the development archive on any Debian FTP site and use them to upgrade your system at any time. It is planned that this will become a new Debian release about three months after the last release. 9. Keeping Your Debian System Up To Date 9.1. How can I upgrade my Debian 0.93 (or earlier) distribution, based on a.out format binaries, to 1.1 (or later), based on ELF binaries? The directory upgrades/ contains files needed by users upgrading from Debian 0.93R6 to Debian 1.1 (or later). There are two ways to upgrade: o the manual way, installing the packages by hand. Instructions are in upgrade_manual.doc. You will also need the files UpGrade, base_list, and dpkg-*.deb. o using dselect to upgrade all the packages en masse. Instructions are in upgrade_dselect.doc. You will also need dpkg-*.deb. Note that the version of dpkg in this directory has the a.out binary format. The versions of dpkg in the development and stable trees have the ELF format. 9.2. How can I keep my Debian system current? One could simply execute an anonymous ftp call to a Debian archive, then peruse the directories until he finds the desired file, and then fetch it, and finally install it using dpkg. Note that dpkg will install upgrade files in place, even on a running system. Sometimes, a revised package will require the installation of a newly revised version of another package, in which case the installation will fail until/unless the other package is installed. Many people find this approach much too time-consuming, since Debian evolves so quickly---typically, a dozen or more new packages are uploaded every week. This number is larger just before a new major release. To deal with this avalanche, many people prefer to use an automated programs. Three different packages are available for this purpose: o dpkg-ftp. This is an access method for dselect. It can be invoked from within dselect, thereby allowing a user the ability to download files and install them directly in one step. To do this, bring up the dselect program, choose option 0 (Choose the access method to use), highlight the option ftp then specify the remote hostname and directory. dpkg-ftp will then automatically download the files that are selected (either in this session of dselect or earlier ones). Note that, unlike the mirror program, dpkg-ftp does not grab everything at a mirror site. Rather, it downloads only those files which you have selected (when first starting up dpkg-ftp), and which need to be updated. dpkg-ftp is available in the directory stable/binary-all/net/ on any Debian archive. o mirror. This Perl script, and its (optional) manager program called mirror-master, can be used to fetch user-specified parts of a directory tree from a specified host via anonymous ftp. mirror is particularly useful for downloading large volumes of software. After the first time files have been downloaded from a site, a file called .mirrorinfo is stored on the local host. Changes to the remote filesystem are tracked automatically by mirror, which compares this file to a similar file on the remote system and downloads only changed files. The mirror program is generally useful for updating local copies of remote directory trees. The files fetched need not be Debian files. (Since mirror is a Perl script, it can also run on non-Unix systems.) Though the mirror program provides mechanisms for excluding files whose names match user-specified strings, this program is most useful when the objective is to download whole directory trees, rather than selected packages. The mirror program has been packaged for Debian, and is found in the directory stable/binary-all/net in the Debian FTP archive. o dftp. This Perl script can be used to fetch user-specified Debian packages from a specified host. It begins by downloading the Packages.gz files for the directories specified by the user (e.g. stable, contrib, non-free) and presents him with a list of packages. These are placed in various sections: new upgrades, downgrades, new packages, ignored upgrades, and ignored packages. The user then selects the packages he wants and dftp downloads and installs them. This makes it very easy to have your Debian system 100% current all the time without downloading packages that you are not going to install. dftp can be used to call dselect (7.1.1), thereby providing an integrated way to fetch and update the Debian packages on one's system. When the installation is finished, another dftp command can be used to remove the package archive (.deb) files. Changes to the remote filesystem are tracked automatically by dftp, which compares the local Packages.gz file to the files on the remote system. The dftp program is available as a script in the directory project/misc in the Debian FTP archive. 9.3. Must I go into single user mode in order to upgrade a package? No. Packages can be upgraded in place, even in running systems. Debian has a start-stop-daemon program that is invoked to stop, then restart running process if necessary during a package upgrade. 9.4. Do I have to keep all those .deb archive files on my disk? No. If you have downloaded the files to your disk (which is not absolutely necessary (see dpkg-ftp (9.2) or dftp (9.2))), then after you have installed the packages, you can remove them from your system. 9.5. How can I keep a log of the packages I added to the system? dpkg keeps a record of the packages that have been unpacked, configured, removed, and/or purged, but does not (currently) keep a log of terminal activity that occured while a package was being so manipulated. Some users overcome this simply by using tee: dpkg -iGOEB -R stable/binary non-free/binary contrib/binary | \ tee -a /root/dpkg.log The same command written using long options: dpkg --install --refuse-downgrade --selected-only \ --skip-same-version --auto-deconfigure \ --recursiv estable/binary non-free/binary contrib/binary | \ tee -a /root/dpkg.log 10. Debian and the kernel 10.1. What tools does Debian provide to build custom kernels? Users who wish to (or must) build a custom kernel are encouraged to download the package kernel-package_VVV_all.deb (it is stored in section misc at the Debian FTP archives). This package contains the script to build the kernel package, and provides the capability to create a Debian kernel-image package just by running the command make-kpkg kernel_image in the top-level kernel source directory. Help is available by executing the command make-kpkg --help, and through the manual page for make-kpkg(8). Users must separately download the source code for the most recent kernel (or the kernel of their choice) from their favorite Linux archive site. To build a custom kernel, users must have these packages installed: gcc, libc5-dev, bin86, binutils, gawk, make, gzip, and grep. Executing the command dpkg --install kernel-package_VVV_all.deb sets up the directory /usr/src/linux-VVV/, and sets up the link /usr/src/linux to point to the directory /usr/src/linux-VVV/ containing the kernel sources. Detailed instructions for using the package are given in the file /usr/doc/kernel-package/README. Briefly, one should: o Unpack the kernel sources, and cd to the newly created directory. o Modify the kernel configuration using one of these commands: -- make config (for a tty one-line-at-a-time-interface). -- make menuconfig (for an ncurses-based menu driven interface). Note that to use this option, the ncurses3.0-dev package must be installed. -- make xconfig (for an X11 interface). Using this option requires that relevant X packages be installed. Any of the above steps generates a new .config in the top-level kernel source directory. o Execute the command: make-kpkg -r Custom.N kernel_image, where N is a revision number assigned by the user. The new Debian archive thus formed would have revision Custom.1, e.g., kernel-image-2.0.27-Custom.1.deb for the Linux kernel 2.0.27. o Install the package created. -- Run dpkg --install /usr/src/kernel-image_VVV-Custom.N.deb to install the kernel itself. The installation script will: * run the boot loader, LILO (if it is installed), * install the custom kernel in /boot/vmlinuz_VVV-Custom.N, and set up appropriate symbolic links to the most recent kernel version. * prompt the user to make a boot floppy. This boot floppy will contain the raw kernel only. See additional notes for making a custom boot floppy (10.2). -- To employ a secondary boot loaders (e.g., loadlin), copy this image to other locations (e.g., an MS-DOS partition). 10.2. How can I make a custom boot floppy? This task is greatly aided by the Debian package boot-floppies_VVV-RRR.deb, normally found in the binary/devel section of the Debian FTP archive. Shell scripts in this package produce boot floppies in the SYSLINUX format. These are MS-DOS formatted floppies whose master boot records have been altered so that they boot Linux directly (or whatever other operating system has been defined in the syslinux.cfg file on the floppy). Other shell scripts in this package produce emergency root disks and can even reproduce the base disks. When the boot-floppies package is installed, it produces files which reside in /usr/src/boot-floppies/, including the three scripts, called bootdisk.sh, rootdisk.sh, and basedisk.sh. Users of these scripts are encouraged to read them and customize as appropriate. In particular, one should include the kernel of your choice when invoking the bootdisk.sh script. Be aware that this kernel cannot be used to load the root disk into a RAMDISK unless it was compiled with CONFIG_RAMDISK=y, and CONFIG_INITRD=y. To write the kernel-image-2.0.27 package to the 1.44 MByte disk in drive A: run this command: ./bootdisk.sh /usr/src/kernel-image-2.0.27_1.00.deb /dev/fd0 1440 Be sure to include the editor and whatever other tools you prefer when building your custom root disk with ./rootdisk.sh. Some people found that the boot and root disks make good emergency floppies. 10.3. What special provisions does Debian provide to deal with modules? Debian's modconf package provides a shell script (/usr/sbin/modconf) which can be used to customize the configuration of modules. This script presents a menu-based interface, prompting the user for particulars on the loadable device drivers in his system. The responses are used to customize the file /etc/conf.modules (which lists aliases, and other arguments that must be used in conjunction with various modules), and /etc/modules (which lists the modules that must be loaded at boot time). Like the (new) Configure.help files that are now available to support the construction of custom kernels, the modconf package comes with a series of help files (in /usr/lib/modules_help/) which provide detailed information on appropriate arguments for each of the modules. 10.4. Can I safely de-install an old kernel, and if so how? Yes. The kernel-image-NNN.prerm script checks to see whether the kernel you are currently running is the same as the kernel you are trying to de-install. Therefore you can remove unwanted kernel image packages using this command: dpkg --purge --force-remove-essential kernel-image-NNN 11. Customizing your installation of Debian GNU/Linux 11.1. How can I ensure that all programs use the same paper size? The file /etc/papersize contains the name of the system-wide default paper size (i.e. letter or A4). It can be overwritten using the PAPERSIZE environment variable. For details see the manual page papersize(5). 11.2. How can I configure an X11 program's application defaults ? Debian's X11 installation expects you to leave the files in /usr/X11R6/lib/X11/app-defaults/ unchanged. If you want to customise X applications globally, put your customizations in /etc/X11/Xresources. This file is marked as a configuration file, so its contents will be preserved during upgrades. 11.3. Every distribution seems to have a different boot-up method. Tell me about Debian's. Like all Unices, Debian boots up by executing the program init. The configuration file for init (which is /etc/inittab) specifies that the first script to be executed should be /etc/init.d/boot. This script checks and mounts file systems, loads modules, starts the network services (by calling the script /etc/init.d/network), sets the clock, performs other initialization, and then runs all of the scripts (except those with a '.' in the filename) in /etc/rc.boot/. The latter script sets the default keyboard, recovers lost editor files, and configures the serial ports. After completing the boot process, init executes all start scripts in a directory specified by the default runlevel (this runlevel is given by the entry for id in /etc/inittab). Like most System V compatible Unices, Linux has 7 runlevels: 0 (halt the system), 1 (single-user mode), 2 through 5 (various multi-user modes), and 6 (reboot the system). Debian systems come with id=2, which indicates that the default runlevel will be '2' when the multi-user state is entered, and the scripts in /etc/rc2.d/ will be run. In fact, the scripts in any of the directories, /etc/rcN.d/ are just symbolic links back to scripts in /etc/init.d/. However, the names of the files in each of the /etc/rcN.d/ directories are selected to indicate the way the scripts in /etc/init.d/ will be run. Specifically, before entering any runlevel, all the scripts beginning with 'K' are run; these scripts kill services. Then all the scripts beginning with 'S' are run; these scripts start services. The two-digit number following the 'K' or 'S' indicates the order in which the script is run. Lower numbered scripts are executed first. This approach works because the scripts in /etc/init.d/ all take an argument which can be either 'start', 'stop', or 'reload', and will then do the task indicated by the argument. For example, with the argument 'reload' the command /etc/init.d/sendmail reload sends the sendmail daemon a signal to reread its configuration file. These scripts can be used even after a system has been booted to control various processes. 11.4. It looks as if Debian does not use rc.local to customize the boot process; what facilities are provided? Suppose a system needs to execute script foo on start-up, or on entry to a particular (System V) runlevel. Then the system administrator should: o Enter the script foo into the directory /etc/init.d/. o Run the Debian command update-rc.d with appropriate arguments, to set up links between the (command-line-specified) directories rc?.d and /etc/init.d/foo. Here, '?' is a number from 0 through 6 and corresponds to each of the System V runlevels. o Reboot the system. The command update-rc.d will set up links between files in the directories rc?.d and the script in /etc/init.d/. Each link will begin with a 'S' or a 'K', followed by a number, followed by the name of the script. Scripts beginning with 'S' in /etc/rcN.d/ are executed when runlevel N is entered. Scripts beginning with a 'K' are executed when leaving runlevel N. One might, for example, cause the script foo to execute at boot-up, by putting it in /etc/init.d/ and installing the links with update-rc.d foo defaults 19. The argument 'defaults' refers to the default runlevels, which are 2 through 5. The argument '19' ensures that foo is called before any scripts containing numbers 20 or larger. 11.5. How does the package management system deal with packages that contain configuration files for other packages? Some users wish to create, for example, a new server by installing a group of Debian packages and a locally generated package consisting of configuration files. This is not generally a good idea, because dpkg will not know about those configuration files if they are in a different package, and may write conflicting configurations when one of the initial group of packages is upgraded. Instead, create a local package that modifies the configuration files of the group of Debian packages of interest. Then dpkg and the rest of the package management system will see that the files have been modified by the local sysadmin and will not try to overwrite them when those packages are upgraded. 11.6. How do I override a file installed by a package so that a different version can be used instead? Suppose a sysadmin or local user wishes to use a program login-local rather than the program login provided by the Debian login package. Do not: o Overwrite /bin/login with login-local. The package management system will not know about this change, and will simply overwrite your custom /bin/login whenever login (or any package that provides /bin/login) is installed or updated. Rather, do o Execute dpkg-divert --divert /bin/login.debian /bin/login in order to cause all future installations of the Debian login packages to write the file /bin/login to /bin/login.debian instead. o Then execute cp login-local /bin/login to move your own locally-built program into place. Some details are given in the usage statement for dpkg-divert (which can be viewed using the command dpkg-divert --help). Additional details are given in the Debian programmer's manual. 11.7. How can I have my locally-built package included in the list of available packages that the package management system knows about? You can do this in either of two ways: o Use dselect, and reselect the access method. You will be asked for a directory where your local packages reside. o Execute the command dpkg-scanpackages BIN_DIR OVERRIDE_FILE [PATHPREFIX] > Packages.new where: - BIN-DIR is a directory where Debian archive files (which usually have an extension of .deb) are stored. - OVERRIDE_FILE is a file that is edited by the distribution maintainers and is usually stored on a Debian FTP archive at indices/override.main.gz for the Debian packages in the main distribution. - PATHPREFIX is an optional string that can be prepended to the Packages.new file being produced. Once you have built the file Packages.new, tell the package management system about it by using the command dpkg --update-avail Packages.new. 11.8. Some users like mawk, others like gawk; some like vim, others like elvis; some like trn, others like tin; how does Debian support diversity? There are several cases where two packages provide two different versions of a program, both of which provide the same core functionality. Users might prefer one over another out of habit, or because the user interface of one package is somehow more pleasing than the interface of another. Other users on the same system might make a different choice. Debian uses a virtual package system to allow system administrators to choose (or let users choose) their favorite tools when there are two or more that provide the same basic functionality, yet satisfy package dependency requirements without specifying a particular package. For example, there might exist two different versions of newsreaders on a system. The news server package might 'recommend' that there exist some news reader on the system, but the choice of tin or trn is left up to the individual user. This is satisfied by having both the tin and trn packages provide the virtual package news-reader. Which program is invoked is determined by a link pointing from a file with the virtual package name /etc/alternatives/news-reader to the selected file, e.g., /usr/bin/trn. A single link is insufficient to support full use of an alternate program; normally, manual pages, and possibly other supporting files must be selected as well. The Perl script update-alternatives provides a way of ensuring that all the files associated with a specified package are selected as a system default. 12. Getting support for Debian Linux 12.1. What other documentation exists on and for a Debian system? o Installation instructions for the current release: see ( http://www.debian.org/1.1/install.html ) . o dpkg programmer's manual and Debian policy manual -- The dpkg programmer's manual ( ftp://ftp.debian.org/debian/doc/package-developer/programmer.ps.gz ) is the primary documentation on the technical aspects of creating Debian binary and source packages. The Debian policy manual ( ftp://ftp.debian.org/debian/doc/package-developer/policy.ps.gz ) documents the policy requirements for a package to be included in Debian. These documents are also included in the latest dpkg-dev package. o Documentation on installed Debian packages: Most packages have files that are unpacked into /usr/doc/ and /usr/doc/examples/. o Documentation on the Linux project: The Debian package doc- linux_VVV-RRR.deb installs all of the most recent versions of the HOWTOs and mini-HOWTOs from the Linux Documentation Project. This package is in the stable/binary-all/doc/ section in the FTP archives. o Unix-style 'man' pages: Most commands have manual pages written in the style of the original Unix 'man' files. They are referenced by the section of the 'man' directory where they reside: e.g., foo(3) refers to a manual page which resides in /usr/man/man3/, and it can be called by executing the command: man 3 foo, or just man foo if section 3 is the only one containing a page on foo. One can learn which directory of /usr/man/ contains a certain manual page by executing man -w foo. New Debian users should note that the 'man' pages of many general system commands are not available until they install these packages (both of which are normally stored in the stable/binary-all/doc/ directory of the Debian FTP archive: - manpages_VVV-RRR.deb (see support for non-English languages (5.11)). - man_VVV-RRR.deb, which contains the man program itself, and other programs for manipulating the manual pages. o GNU-style 'info' pages: User documentation for many commands, particularly GNU tools, is available not in 'man' pages, but in 'info' files which can be read by the GNU tool info or by running M-x info within GNU Emacs. Its main advantage over the original 'man' pages are that it is a hypertext system. It does not require the WWW, however; info can be run from a plain text console. It was designed by Richard Stallman and preceded the WWW. The program that manipulates `info' files is installed as a separate package info_VVV-RRR.deb, usually stored in the directory stable/binary-all/doc/ on the FTP archive. 12.2. Are there any on-line resources for discussing Debian? There are several Debian-related mailing lists: o debian-announce@lists.debian.org (moderated). (Usually) major system announcements. On average, fewer than one message per week are posted here. o debian-changes@lists.debian.org. Announcements of new package uploads for the Debian system. This list may carry several announcements in a day. o debian-user@lists.debian.org. A mailing list where users can ask for and receive advice on the use or configuration of Debian packages or other aspects of Debian Linux. This list is an invaluable learning resource; there can be 50 messages a day or more on this list. o debian-sparc@lists.debian.org. This list is for those involved in porting Debian software to the SPARC platform. o debian-alpha@lists.debian.org. This list is for those involved in porting Debian software to DEC alpha platforms. o debian-68k@lists.debian.org. This list is for those involved in porting Debian software to Motorola 680x0 platforms; currently this means the Atari and Amiga only. o debian-talk@lists.debian.org. To subscribe to debian-X (for X in announce, changes, user, talk), send mail to debian-X-request@lists.debian.org with the word subscribe in the Subject: header. If you have a forms-capable World Wide Web browser, you can subscribe to debian-announce and debian-user by using the WWW form( http://www.rahul.net/perens/Debian/MailingLists.html ) . You can also un-subscribe using that form. The list manager's e-mail address is listmaster@lists.debian.org Archives of the Debian mailing lists are available via WWW at ( http://www.debian.org/Lists-Archives/ ) and via FTP from ( ftp://ftp.debian.org/debian/debian-lists/ ) . Users can address questions to individual package maintainers, since their e-mail addresses are provided in the Debian control file (see section Debian control file (6.4)) that is included within each package. One can also learn the maintainers' names and e-mail addresses by searching the Packages file, since this file is just a concatenation of all the available package control files in a particular directory tree. To extract a control file from a particular Debian package, use the command, dpkg --info packageName_VVV-RRR.deb Another related mailing list, debiangame, is being run by Gary Moore ( ( mailto:gary@ssc.com ) ) at the University of Washington. As the name suggests, it is devoted to the discussion of games that have been (or might be) packaged for Debian. To subscribe, send mail to listproc@u.washington.edu, putting in the message body: subscribe debiangame FirstName LastName Both FirstName and LastName are required for ListProc. Users should post non-Debian-specific questions to one of the Linux Usenet groups, which are named comp.os.linux.* or linux.*. Specialized Systems Consultants (a.k.a. SSC) maintains a list of Linux, Unix, X, and networking newsgroups ( http://www.ssc.com/linux/news.html ) on their WWW site. 12.3. What is the code of conduct for the mailing lists? When using the Debian mailing lists, please follow these rules: o Do not flame; it is not polite. Besides the people developing Debian are all volunteers, donating their time, energy and money in an attempt to bring the Debian project together. o Do not use foul language; some people receive the lists via packet radio, where swear words are illegal. o Make sure that you are using the proper list. o Do not try posting unless you are subscribed. Posting by non-subscribers was turned off to make the mailing lists usable. Thus, only postings from e-mail addresses matching those of a subscriber are accepted. If you often post from other addresses than the one you subscribe with, mail the list manager listmaster@lists.debian.org with the subject please add subscriber alias. o See section reporting bugs (13.2) for notes on reporting bugs. 12.4. Is there a quick way to search for information on Debian GNU/Linux? There are a variety of search engines that serve documentation related to Debian. o Verism's search site. To obtain information on how to submit a debian bug report, enter the words debian bug submit and search for all of these words. o DejaNews news search service. To find out what experiences people have had with finding drivers for Western Digital controllers, try searching on this phrase: linux & WD This tells DejaNews to report any postings containing both the string linux AND the string WD When I used it, I discovered that my WD card (which I have only had for 6 months) has been declared outmoded by Adaptec, now that they have bought WD. So there are no drivers available. (Bless Adaptec's hearts.) o The AltaVista Search Engine can also be used to search Usenet (although it appears to be not quite as up to date as DejaNews). For example, searching on the string "cgi-perl" gives a more detailed explanation of this package than the brief description field in its control file. 13. The Debian Bug Report System 13.1. Are there logs of known bugs? The Debian Linux distribution has a bug tracking system which files details of bugs reported by users and developers. Each bug is given a number, and is kept on file until it is marked as having been dealt with. Copies of this information are available at ( http://www.cl.cam.ac.uk/users/iwj10/debian-bugs/ ) and ( http://www.debian.org/Bugs/ ) , but the latter is not up-to-date at present. A mail server provides access to the bug tracking system database via e-mail. In order to get the instructions send an e-mail to request@bugs.debian.org with "help" in the body. 13.2. How do I report a bug in Debian? If you have found a bug in Debian, please read the instructions for reporting a bug in Debian. These instructions can be obtained in one of several ways: o By anonymous ftp. Debian mirror sites contain the instructions in the file doc/bug-reporting.txt. o From the WWW. A copy of the instructions is shown at ( http://www.cl.cam.ac.uk/users/iwj10/debian-bugs/Reporting.html ) o On any Debian system with the doc-debian package installed. The instructions are in the file /usr/doc/debian/bug-reporting.txt. Use these mail addresses for bugs: o submit@bugs.debian.org: for general bug reports. Expect to get an automatic acknowledgement of your bug report. It will also be automatically given a bug tracking number, entered into the bug log and forwarded to the debian-devel mailing list. o maintonly@bugs.debian.org: to send bug reports to the maintainer only. It will not be forwarded to the debian-devel mailing list. For example, if one were to identify a bug that was common to many programs, then rather than entering dozens of bug reports, one might prefer to send individual bugs to maintonly, then send a summary report to debian-devel. o quiet@bugs.debian.org: to submit bug reports to the bug log only, without having them sent either to debian-devel or to the maintainer. 14. Contributing to the Debian project Donations of time (to develop new packages, maintain existing packages, or provide user support), resources (to mirror the FTP and WWW archives), and money (to pay for new testbeds as well as hardware for the archives) can help the project. 14.1. How can I become a Debian software developer? The development of Debian is open to all, and new users with the right skills and/or the willingness to learn are needed to maintain existing packages which have been orphaned by their previous maintainers, to develop new packages, and to provide user support. To develop a Debian package, you should: o (of course) download Debian and install it on your system. o find a program you would like to package that is not presently part of Debian. In this regard, the Work Needing and Prospective Packages document (available as /debian/doc/package-developer/prospective-packages.txt at the Debian FTP server) should serve as a useful guide. o Subscribe to debian-devel. To do this execute mail debian-devel-REQUEST@lists.debian.org -s Subscribe That is, send mail to the above address with the subject set to 'Subscribe'. o Set up your PGP key. Install the PGP package; read /usr/doc/pgp/; generate a public-secret key pair by typing pgp -kg and answering the questions. (Be prepared to write some arbitrary text when asked. PGP generates its true random numbers by measuring the intervals between your keystrokes.) o Shake hands with the project administration: Send an e-mail to new-maintainer@debian.org with this content: - what you have done, - who you are, - request for an account on master, - request to be subscribed to debian-private (the developers-only mailing list). - your PGP key, obtained by executing 'pgp -kxa'. o Make the programs: .deb, .diff, .tar.gz, .changes. Use the hello*deb and dpkg*deb packages as guides, and read the policy manual and dpkg programmers manual. o Upload the files to - ftp://master.debian.org/home/Debian/ftp/private/project/Incoming/ using your user-name and password, or - ftp://ftp.chiark.greenend.org.uk/ using anonymous ftp. For instructions to upload to chiark, read this file at chiark: /pub/debian/private/project/README.how-to-upload. chiark then sends the files it gets to master. 14.1.1 Are there additional information resources for developers? Besides debian-devel, there are these mailing lists: o The SPARC port developers list: debian-sparc@lists.debian.org. o The Alpha port developers list: debian-alpha@lists.debian.org. o The Motorola 680x0 port developers list: debian-68k@lists.debian.org. o The dpkg development list: debian-dpkg@lists.debian.org. o Debian for Hams: debian-hams@lists.debian.org. o Debian package maintainers only: debian-private@lists.debian.org. To subscribe to debian-devel, or other developers' list, send a message to listmaster@lists.debian.org with a one-line explanation of what you would like to test or develop. 14.2. How can I contribute resources to the Debian project? Since the project aims to make a substantial body of software rapidly and easily accessible throughout the globe, mirrors are urgently needed. It is desirable but not absolutely necessary to mirror all of the archive. The current components amount to just over 1.4 GBytes, broken down roughly as follows: o non-free: 100 MBytes. o contrib: 50 MBytes. o Debian-1.2 (including updates): 650 MBytes. o unstable: 200 MBytes. o mailing list archives: 20 MBytes. Most of the mirroring is accomplished entirely automatically by scripts, without any human intervention. However, the occasional glitch or system change occurs which requires human intervention. If you have a high-speed connection to the Internet, the resources to mirror all or part of the distribution, and are willing to take the time (or find someone) who can provide regular maintenance of the system, then please contact Bruce Perens (E-Mail: bruce@pixar.com; Voice (work): 510-215-3502). 14.3. How can I contribute financially to the Debian project? One can make individual donations to one of two organizations that are critical to the development of the Debian project. 14.3.1 Software in the Public Interest Software in the Public Interest (SPI) is a non-profit organization formed when FSF withdrew their sponsorship of Debian. We are currently incorporating as an IRS 501(c)(3) non-profit organization. The purpose of the organization is to develop and distribute free software. Our goals are very much like those of FSF, and we encourage programmers to use the GNU General Public License on their programs. However, we have a slightly different focus in that we are building and distributing a Linux system that diverges in many technical details from the GNU system planned by FSF. We still communicate with FSF, and we cooperate in sending them changes to GNU software and in asking our users to donate to FSF and the GNU project. SPI can be reached at: o E-Mail: bruce@pixar.com o Postal address: Software in the Public Interest P.O. Box 70152 Pt. Richmond, CA 94807-0152 o Phone: 510-215-3502 (Bruce Perens at work) 14.3.2 Free Software Foundation At this time there is no formal connection between Debian and the Free Software Foundation. However, the Free Software Foundation is responsible for some of the most important software components in Debian, including the GNU C compiler, GNU Emacs, and much of the C run-time library that is used by all programs on the system. FSF pioneered much of what free software is today: they wrote the the General Public License that is used on much of the Debian software, and they invented the "GNU" project to create an entirely free Unix system. Debian should be considered a descendent of the GNU system. When you make a donation to FSF, please be sure to tell them that you are a Debian user. Please contact them at: o E-mail: gnu@prep.ai.mit.edu o Postal address: Free Software Foundation 59 Temple Place - Suite 330 Boston, MA 02111-1307 USA o Phone number: +1-617-542-5942 o Fax (including Japan): +1-617-542-2652 o Free Dial Fax (in Japan): 0031-13-2473 (KDD), 0066-3382-0158 (IDC) o On the WWW : ( http://www.gnu.ai.mit.edu/ ) 15. Redistributing Debian GNU/Linux in a commercial product 15.1. Can I make and sell Debian CDs? Go ahead. You do not need permission to distribute anything we have released, so that you can master your CD as soon as the beta-test ends. You do not have to pay us anything. We will, however, publish a list of CD manufacturers who donate money, software, and time to the Debian project, and we will encourage users to buy from manufacturers who donate, so it is good advertising to make donations. Of course all CD manufacturers must honor the licenses of the programs in Debian. For example, many of the programs are licensed under the GPL, which requires you to distribute their source code. 15.2. Can Debian be packaged with non-free software? Yes. While all the main components of Debian are free software, we provide a non-free directory for programs that are not freely redistributable. CD manufacturers may be able to distribute the programs we have placed in that directory, depending on the license terms or their private arrangements with the authors of those software packages. CD manufacturers can also distribute the non-free software they get from other sources on the same CD. This is nothing new: free and commercial software are distributed on the same CD by many manufacturers now. Of course we still encourage software authors to release the programs they write as free software. 15.3. I am making a special Linux distribution for a vertical market. Can I use Debian GNU/Linux for the guts of a Linux system and add my own applications on top of it? Yes. For example, one person is building a Linux for Hams distribution, with specialized programs for Radio Amateurs. He is starting with Debian as the base system, and adding programs to control the transmitter, track satellites, etc. All of the programs he adds are packaged with the Debian package system so that his users will be able to upgrade easily when he releases subsequent CDs. Debian also provides a mechanism to allow developers and system administrators to install local versions of selected files in such a way that they will not be overwritten when other packages are upgraded. This is discussed further in the question on diversions (11.6). 15.4. Can I put my commercial program in a Debian package so that it installs effortlessly on any Debian system? Go right ahead. The package tool is free software. 16. What kind of changes should I expect to see in the next major release of Debian Linux? 16.1. A New Approach to the Boot Floppies In order to accommodate all of the hardware for which Linux drivers have been written, yet still provide boot-floppies that can fit on a 5.25-inch disk, Debian 1.2 will provide a mechanism to access all drivers that can be modularized as modules. (This work is partially done.) The default kernel has no IDE, no SCSI, little else. When the user sets up the system, it builds a RAM disk image that is loaded at boot time. The script on the RAM disk loads the modules for your local hardware configuration _before_ it mounts the root. Some things that still are not modularized are in the default kernel. The stripped-down kernel and the compressed installation root filesystem fit on one 1200K floppy and run fine that way. The floppy also contains a few of the most popular modules, and you get to feed it more floppies (or a CD) containing other modules depending on your configuration. No-floppy bootstrap should be possible for systems with 8MByte RAM and a CD or DOS hard disk. One-floppy NFS bootstrap should be possible. See /usr/src/linux/Documentation/initrd.txt . 16.2. Increased security Debian will be equipped with the Shadow password suite of programs and library routines which hide the plain text of the password file from all users except root and provide for terminal access control, and user and group administration. For details, see ( http://sunsite.unc.edu/mdw/HOWTO/Shadow-Password-HOWTO.html ) . This document is of course also included along with all the HOWTOs in the Debian doc-linux package. Most of the relevant Debian utilities have been modified to make them support shadow passwords. This includes the default login utility, as well as vipw and vigr. The xdm X11 login utility and the adduser script will be made shadow aware as well. In addition, there will be minor changes to the shadow packages themselves. In addition, the Linux library of Pluggable Authentication Modules ( ( http://parc.power.net/morgan/Linux-PAM/ ) ; a.k.a. libpam) that allow sysadmins to choose authorization modes on an application-specific basis will be available, and initially set to authenticate via shadow password. 16.3. More Support for non-English users Debian already has some support for non-English users (5.11). We hope to find people who provide support for even more languages. Some programs already support internationalization, so we need message catalogs. Many programs still must be internationalized. 16.4. More architectures Currently a complete Debian release is only available for the i386 architecture. Complete Debian system on other architectures are expected soon.