Provided by: apt_1.0.10.2ubuntu1_i386 bug


       sources.list - List of configured APT data sources


       The source list /etc/apt/sources.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
       information available from the configured sources is acquired by
       apt-get update (or by an equivalent command from another APT

       Each line specifying a source starts with type (e.g.  deb-src) followed
       by options and arguments for this type. Individual entries cannot be
       continued onto a following line. Empty lines are ignored, and a #
       character anywhere on a line marks the remainder of that line as 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, unless that file matches a pattern in the
       Dir::Ignore-Files-Silently configuration list - in which case it will
       be silently ignored.


       The deb type references a typical two-level Debian archive,
       distribution/component. The distribution is generally an archive name
       like stable or testing or a codename like jessie or stretch while
       component is one of main, contrib or non-free. The deb-src type
       references 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 suite [component1] [component2] [...]

       Alternatively a rfc822 style format is also supported:

                Types: deb deb-src
                Suites: stable testing
                Sections: component1 component2
                Description: short
                 long long long
                [option1]: [option1-value]

                Types: deb
                Suites: experimental
                Sections: component1 component2
                Enabled: no
                Description: short
                 long long long
                [option1]: [option1-value]

       The URI for the deb type must specify the base of the Debian
       distribution, from which APT will find the information it needs.  suite
       can specify an exact path, in which case the components must be omitted
       and suite must end with a slash (/). This is useful for the case when
       only a particular sub-section of the archive denoted by the URI is of
       interest. If suite does not specify an exact path, at least one
       component must be present.

       suite may also contain a variable, $(ARCH) which expands to the Debian
       architecture (such as amd64 or armel) 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 otherwise.

       In the traditional style sources.list format 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 surrounded 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 however that unsupported settings
       will be ignored silently):

       ·   arch=arch1,arch2,...  can be used to specify for which
           architectures information should be downloaded. If this option is
           not set all architectures defined by the APT::Architectures option
           will be downloaded.

       ·   arch+=arch1,arch2,...  and arch-=arch1,arch2,...  which can be used
           to add/remove architectures from the set which will be downloaded.

       ·   trusted=yes can be set to indicate that packages from this source
           are always authenticated 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
           authenticated sources as not authenticated.

       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).

       Some examples:

           deb jessie main contrib non-free
           deb jessie/updates main contrib non-free


       The currently recognized URI types are:

           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 CD-ROM 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 an FTP proxy can be
           specified by using the ftp_proxy environment variable. It is
           possible to specify an HTTP proxy (HTTP proxy servers often
           understand FTP URLs) using this environment variable and only this
           environment variable. Proxies using HTTP specified in the
           configuration file will be ignored.

           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
           removable media to copy files around with APT.

       rsh, ssh
           The rsh/ssh method invokes RSH/SSH to connect to a remote host and
           access the files as a given user. Prior configuration of rhosts or
           RSA keys is recommended. The standard find and dd commands are used
           to perform the file transfers from the remote host.

       adding more recognizable URI types
           APT can be extended with more methods shipped in other optional
           packages, which should follow the naming scheme
           apt-transport-method. For instance, the APT team also maintains the
           package apt-transport-https, which provides access methods for
           HTTPS URIs with features similar to the http method. Methods for
           using e.g. debtorrent are also available - see apt-transport-


       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 jessie main
           deb [ arch=amd64,armel ] jessie main

       Uses HTTP to access the archive at, and uses only
       the hamm/main area.

           deb hamm main

       Uses FTP to access the archive at, under the debian
       directory, and uses only the jessie/contrib area.

           deb jessie contrib

       Uses FTP to access the archive at, 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 unstable contrib

       Uses HTTP to access the archive at, 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 unstable/binary-$(ARCH)/




       APT bug page[1]. If you wish to report a bug in APT, please see
       /usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.


       Jason Gunthorpe

       APT team


        1. APT bug page