Chapter?6.?The Debian archives
6.1.?How many Debian distributions are there?
There are three major distributions: the "stable" distribution, the "testing"
distribution, and the "unstable" distribution. The "testing" distribution is
sometimes `frozen' (see
Section?6.5.1, “What about "testing"? How is it `frozen'?”
). Next to these, there is the
"oldstable" distribution (that's just the one from before "stable"), and the
"experimental" distribution.
Experimental is used for packages which are still being developed, and with a
high risk of breaking your system. It's used by developers who'd like to study
and test bleeding edge software. Users shouldn't be using packages from there,
because they can be dangerous and harmful even for the most experienced people.
See
Chapter?3,
Choosing a Debian distribution
for help when choosing a Debian distribution.
6.2.?What are all those names like etch, lenny, etc.?
They are just "codenames". When a Debian distribution is in the development
stage, it has no version number but a codename. The purpose of these codenames
is to make easier the mirroring of the Debian distributions (if a real
directory like
unstable
suddenly changed its name to
stable
, a lot of stuff would have to be needlessly
downloaded again).
Currently,
stable
is a symbolic link to
bullseye
(i.e. Debian GNU/Linux 11) and
testing
is a symbolic link to
bookworm
.
This means that
bullseye
is the current stable distribution
and
bookworm
is the current testing distribution.
unstable
is a permanent symbolic link to
sid
, as
sid
is always the unstable
distribution (see
Section?6.3, “What about "sid"?”
).
6.2.1.?Which other codenames have been used in the past?
Aside
bullseye
and
bookworm
, other codenames
that have been already used are:
buzz
for release 1.1,
rex
for release 1.2,
bo
for releases
1.3.x,
hamm
for release 2.0,
slink
for
release 2.1,
potato
for release 2.2,
woody
for release 3.0,
sarge
for release
3.1,
etch
for release 4.0,
lenny
for
release 5.0,
squeeze
for release 6.0,
wheezy
for release 7,
jessie
for release
8,
stretch
for release 9,
buster
for release 10.
6.2.2.?Where do these codenames come from?
So far they have been characters taken from the "Toy Story" movies by Pixar.
buzz
(Debian 1.1) was the spaceman Buzz Lightyear,
rex
(Debian 1.2) was the tyrannosaurus,
bo
(Debian 1.3) was Bo Peep, the girl who took care of the sheep,
hamm
(Debian 2.0) was the piggy bank,
slink
(Debian 2.1) was Slinky Dog, the toy dog,
potato
(Debian 2.2) was, of course, Mr. Potato,
woody
(Debian 3.0) was the cowboy,
sarge
(Debian 3.1) was the sergeant of the Green Plastic Army Men,
etch
(Debian 4.0) was the toy whiteboard (Etch-a-Sketch),
lenny
(Debian 5.0) was the toy binoculars,
squeeze
(Debian 6) was the name of the three-eyed aliens,
wheezy
(Debian 7) was the rubber toy penguin with a red
bow tie,
jessie
(Debian 8) was the yodeling cowgirl,
stretch
(Debian 9) was the rubber toy octopus with suckers
on her eight long arms.
buster
(Debian 10) was Andy's pet dog.
bullseye
(Debian 11) was Woody's wooden toyhorse.
bookworm
(Debian 12) was a green toy worm with a built-in
flashlight who loves reading books.
trixie
(Debian 13) was a blue plastic triceratops.
sid
was the evil neighbor kid next door who broke all
toys.
The
decision
of using Toy Story names was
made
by Bruce Perens who was, at the time, the Debian Project Leader and was working
also at Pixar, the company that produced the movies.
sid
or
unstable
is the place where
most of the packages are initially uploaded. It will never be released
directly, because packages which are to be released will first have to be
included in
testing
, in order to be released in
stable
later on. sid contains packages for both released
and unreleased architectures.
The name "sid" also comes from the "Toy Story" animated motion picture: Sid was
the boy next door who destroyed toys :-)
6.4.?What does the stable directory contain?
stable/main/: This directory contains the packages which formally constitute
the most recent release of the Debian GNU/Linux system.
These packages all comply with the
Debian Free Software
Guidelines
, and are all freely usable and distributable.
stable/non-free/: This directory contains packages distribution of which is
restricted in a way that 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
free software. 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).
stable/contrib/: This directory contains packages which are DFSG-free and
freely distributable
themselves, but somehow depend on a
package that is
not
freely distributable and thus
available only in the non-free section.
6.5.?What does the testing distribution contain?
Packages are installed into the `testing' directory after they have undergone
some degree of testing in
unstable
.
They must be in sync on all architectures where they have been built and
mustn't have dependencies that make them uninstallable; they also need to have
fewer release-critical bugs than the versions currently in unstable. This way,
we hope that `testing' is always close to being a release candidate.
More information about the status of "testing" in general and the individual
packages is available at
https://www.debian.org/devel/testing
.
6.5.1.?What about "testing"? How is it `frozen'?
When the "testing" distribution is mature enough, the release manager starts
`freezing' it. The normal propagation delays are increased to ensure that as
few new bugs as possible from "unstable" enter "testing".
After a while, the "testing" distribution becomes truly `frozen'. This means
that all new packages that are to propagate to the "testing" are held back,
unless they include release-critical bug fixes. The "testing" distribution can
also remain in such a deep freeze during the so-called `test cycles', when the
release is imminent.
When a "testing" release becomes `frozen', "unstable" tends to partially freeze
as well. This is because developers are reluctant to upload radically new
software to unstable, in case the frozen software in testing needs minor
updates and to fix release critical bugs which keep testing from becoming
"stable".
We keep a record of bugs in the "testing" distribution that can hold off a
package from being released, or bugs that can hold back the whole release. For
details, please see
current testing release
information
.
Once that bug count lowers to maximum acceptable values, the frozen "testing"
distribution is declared "stable" and released with a version number.
The most important bug count is the "Release Critical" bug count, which can be
followed in the
Release-critical bug status
page
. A common release goal is
NoRCBugs
which means
that the distribution should not have any bugs of severity critical, grave or
serious. The full list of issues considered critical can be found in the
RC policy
document
.
With each new release, the previous "stable" distribution becomes obsolete and
moves to the archive. For more information please see
Debian archive
.
6.6.?What does the unstable distribution contain?
The `unstable' directory contains a snapshot of the current development system.
Users are welcome to use and test these packages, but are warned about their
state of readiness. The advantage of using the unstable distribution is that
you are always up-to-date with the latest in GNU/Linux software industry, but
if it breaks: you get to keep both parts :-)
There are also main, contrib and non-free subdirectories in `unstable',
separated on the same criteria as in `stable'.
6.7.?What are all those directories at the Debian archives?
The software that has been packaged for Debian GNU/Linux is available in one of
several directory trees on each Debian mirror site.
The
dists
directory is short for "distributions", and it is
the canonical way to access the currently available Debian releases (and
pre-releases).
The
pool
directory contains the actual packages, see
Section?6.10, “What's in the
pool
directory?”
.
There are the following supplementary directories:
- /tools/
:
DOS utilities for creating boot disks, partitioning your disk drive,
compressing/decompressing files, and booting Linux.
- /doc/
:
The basic Debian documentation, such as this FAQ, the bug reporting system
instructions, etc.
- /indices/
:
various indices of the site (the Maintainers file and the override files).
- /project/
:
mostly developer-only materials and some miscellaneous files.
6.8.?What are all those directories inside
dists/stable/main
?
Within each of the major directory trees
, there are
three sets of subdirectories containing index files.
There's one set of
binary-
something
subdirectories
which contain index files for binary packages of each available computer
architecture, for example
binary-i386
for packages which
execute on Intel x86 PC machines or
binary-sparc
for
packages which execute on Sun SPARCStations.
The complete list of available architectures for each release is available at
the release's web page
.
For the current release, please see
Section?4.1, “On what hardware architectures/systems does Debian GNU/Linux run?”
.
The index files in binary-* are called Packages(.gz, .bz2) and they include a
summary of each binary package that is included in that distribution. The
actual binary packages reside in the top level
pool
directory
.
Furthermore, there's a subdirectory called source/ which contains index files
for source packages included in the distribution. The index file is called
Sources(.gz, .bz2).
Last but not least, there's a set of subdirectories meant for the installation
system index files, they are at
debian-installer/binary-
architecture
.
6.9.?Where is the source code?
Source code is included for everything in the Debian system. Moreover, the
license terms of most 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.
The source code is distributed in the
pool
directory (see
Section?6.10, “What's in the
pool
directory?”
) together with all the architecture-specific binary
directories. To retrieve the source code without having to be familiar with
the structure of the archive, try a command like
apt-get source
mypackagename
.
Due to restrictions in their licenses, source code may or may not be available
for packages in the "contrib" and "non-free" areas, which are not formally part
of the Debian system. In some cases only sourceless "binary blobs" can be
distributed (see for instance
firmware-misc-nonfree
); in
other cases the license prohibits the distribution of prebuilt binaries, but
does allow packages of source code which users can compile locally (see
broadcom-sta-dkms
).
6.10.?What's in the
pool
directory?
Packages are kept in a large `pool', structured according to the name of the
source package. To make this manageable, the pool is subdivided by section
(`main', `contrib' and `non-free') and by the first letter of the source
package name. These directories contain several files: the binary packages for
each architecture, and the source packages from which the binary packages were
generated.
You can find out where each package is placed by executing a command like
apt-cache showsrc mypackagename
and looking at the
`Directory:' line. For example, the
apache
packages are
stored in
pool/main/a/apache/
.
Additionally, since there are so many
lib*
packages, these
are treated specially: for instance, libpaper packages are stored in
pool/main/libp/libpaper/
.
6.11.?What is "incoming"?
After a developer uploads a package, it stays for a short while in the
"incoming" directory before it is checked that it's genuine and allowed into
the archive.
Usually nobody should install things from this place. However, in some rare
cases of emergency, the incoming directory is available at
https://incoming.debian.org/
. You can
manually fetch packages, check the GPG signature and MD5sums in the .changes
and .dsc files, and then install them.
6.12.?How do I set up my own apt-able repository?
If you have built some private Debian packages which you'd like to install
using the standard Debian package management tools, you can set up your own
apt-able package archive. This is also useful if you'd like to share your
Debian packages while these are not distributed by the Debian project.
Instructions on how to do this are given on the
Debian Wiki
.