Provided by: apt_0.8.16~exp12ubuntu10_i386
sources.list - Package resource list for APT
The package resource list is used to locate archives of the package
distribution system in use on the system. At this time, this manual
page documents only the packaging system used by the Debian GNU/Linux
system. This control file is /etc/apt/sources.list.
The source list is designed to support any number of active sources and
a variety of source media. The file lists one source per line, with the
most preferred source listed first. The format of each line is: type
uri args The first item, type determines the format for args. uri is a
Universal Resource Identifier (URI), which is a superset of the more
specific and well-known Universal Resource Locator, or URL. The rest of
the line can be marked as a comment by using a #.
The /etc/apt/sources.list.d directory provides a way to add
sources.list entries in separate files. The format is the same as for
the regular sources.list file. File names need to end with .list and
may only contain letters (a-z and A-Z), digits (0-9), underscore (_),
hyphen (-) and period (.) characters. Otherwise APT will print a notice
that it has ignored a file if the file doesn't match a pattern in the
Dir::Ignore-Files-Silently configuration list - in this case it will be
THE DEB AND DEB-SRC TYPES
The deb type describes a typical two-level Debian archive,
distribution/component. Typically, distribution is generally an
archivename like stable or testing or a codename like squeeze or wheezy
while component is one of main contrib or non-free. The deb-src type
describes a debian distribution's source code in the same form as the
deb type. A deb-src line is required to fetch source indexes.
The format for a sources.list entry using the deb and deb-src types is:
deb [ options ] uri distribution [component1] [component2] [...]
The URI for the deb type must specify the base of the Debian
distribution, from which APT will find the information it needs.
distribution can specify an exact path, in which case the components
must be omitted and distribution must end with a slash (/). This is
useful for when the case only a particular sub-section of the archive
denoted by the URI is of interest. If distribution does not specify an
exact path, at least one component must be present.
distribution may also contain a variable, $(ARCH) which expands to the
Debian architecture (i386, m68k, powerpc, ...) used on the system. This
permits architecture-independent sources.list files to be used. In
general this is only of interest when specifying an exact path, APT
will automatically generate a URI with the current architecture
Since only one distribution can be specified per line it may be
necessary to have multiple lines for the same URI, if a subset of all
available distributions or components at that location is desired. APT
will sort the URI list after it has generated a complete set
internally, and will collapse multiple references to the same Internet
host, for instance, into a single connection, so that it does not
inefficiently establish an FTP connection, close it, do something else,
and then re-establish a connection to that same host. This feature is
useful for accessing busy FTP sites with limits on the number of
simultaneous anonymous users. APT also parallelizes connections to
different hosts to more effectively deal with sites with low bandwidth.
options is always optional and needs to be surounded by square
brackets. It can consist of multiple settings in the form
setting=value. Multiple settings are separated by spaces. The following
settings are supported by APT, note though that unsupported settings
will be ignored silently:
o arch=arch1,arch2,... can be used to specify for which
architectures packages information should be downloaded. If this
option is not set all architectures defined by the
APT::Architectures option will be downloaded.
o trusted=yes can be set to indicate that packages from this source
are always authenificated even if the Release file is not signed or
the signature can't be checked. This disables parts of apt-
secure(8) and should therefore only be used in a local and trusted
context. trusted=no is the opposite which handles even correctly
authenificated sources as not authenificated.
It is important to list sources in order of preference, with the most
preferred source listed first. Typically this will result in sorting by
speed from fastest to slowest (CD-ROM followed by hosts on a local
network, followed by distant Internet hosts, for example).
deb http://ftp.debian.org/debian squeeze main contrib non-free
deb http://security.debian.org/ squeeze/updates main contrib non-free
The currently recognized URI types are cdrom, file, http, ftp, copy,
The file scheme allows an arbitrary directory in the file system to
be considered an archive. This is useful for NFS mounts and local
mirrors or archives.
The cdrom scheme allows APT to use a local CDROM drive with media
swapping. Use the apt-cdrom(8) program to create cdrom entries in
the source list.
The http scheme specifies an HTTP server for the archive. If an
environment variable http_proxy is set with the format
http://server:port/, the proxy server specified in http_proxy will
be used. Users of authenticated HTTP/1.1 proxies may use a string
of the format http://user:pass@server:port/. Note that this is an
insecure method of authentication.
The ftp scheme specifies an FTP server for the archive. APT's FTP
behavior is highly configurable; for more information see the
apt.conf(5) manual page. Please note that a ftp proxy can be
specified by using the ftp_proxy environment variable. It is
possible to specify a http proxy (http proxy servers often
understand ftp urls) using this method and ONLY this method. ftp
proxies using http specified in the configuration file will be
The copy scheme is identical to the file scheme except that
packages are copied into the cache directory instead of used
directly at their location. This is useful for people using a zip
disk to copy files around with APT.
The rsh/ssh method invokes rsh/ssh to connect to a remote host as a
given user and access the files. It is a good idea to do prior
arrangements with RSA keys or rhosts. Access to files on the remote
uses standard find and dd commands to perform the file transfers
from the remote.
more recognizable URI types
APT can be extended with more methods shipped in other optional
packages which should follow the nameing scheme
apt-transport-method. The APT team e.g. maintains also the
apt-transport-https package which provides access methods for
https-URIs with features similar to the http method, but other
methods for using e.g. debtorrent are also available, see apt-
Uses the archive stored locally (or NFS mounted) at /home/jason/debian
for stable/main, stable/contrib, and stable/non-free.
deb file:/home/jason/debian stable main contrib non-free
As above, except this uses the unstable (development) distribution.
deb file:/home/jason/debian unstable main contrib non-free
Source line for the above
deb-src file:/home/jason/debian unstable main contrib non-free
The first line gets package information for the architectures in
APT::Architectures while the second always retrieves amd64 and armel.
deb http://ftp.debian.org/debian squeeze main
deb [ arch=amd64,armel ] http://ftp.debian.org/debian squeeze main
Uses HTTP to access the archive at archive.debian.org, and uses only
the hamm/main area.
deb http://archive.debian.org/debian-archive hamm main
Uses FTP to access the archive at ftp.debian.org, under the debian
directory, and uses only the squeeze/contrib area.
deb ftp://ftp.debian.org/debian squeeze contrib
Uses FTP to access the archive at ftp.debian.org, under the debian
directory, and uses only the unstable/contrib area. If this line
appears as well as the one in the previous example in sources.list a
single FTP session will be used for both resource lines.
deb ftp://ftp.debian.org/debian unstable contrib
Uses HTTP to access the archive at ftp.tlh.debian.org, under the
universe directory, and uses only files found under
unstable/binary-i386 on i386 machines, unstable/binary-amd64 on amd64,
and so forth for other supported architectures. [Note this example only
illustrates how to use the substitution variable; official debian
archives are not structured like this]
deb http://ftp.tlh.debian.org/universe unstable/binary-$(ARCH)/
APT bug page. If you wish to report a bug in APT, please see
/usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.
1. APT bug page