doc/sources.list.5.xml

   1 <?xml version="1.0" encoding="utf-8" standalone="no"?>
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
   4 <!ENTITY % aptent SYSTEM "apt.ent"> %aptent;
   5 <!ENTITY % aptverbatiment SYSTEM "apt-verbatim.ent"> %aptverbatiment;
   6 <!ENTITY % aptvendor SYSTEM "apt-vendor.ent"> %aptvendor;
   7 ]>
   8
   9 <refentry>
  10
  11  <refentryinfo>
  12    &apt-author.jgunthorpe;
  13    &apt-author.team;
  14    &apt-email;
  15    &apt-product;
  16    <!-- The last update date -->
  17    <date>2014-01-18T00:00:00Z</date>
  18  </refentryinfo>
  19
  20  <refmeta>
  21    <refentrytitle>sources.list</refentrytitle>
  22    <manvolnum>5</manvolnum>
  23    <refmiscinfo class="manual">APT</refmiscinfo>
  24  </refmeta>
  25
  26  <!-- Man page title -->
  27  <refnamediv>
  28     <refname>sources.list</refname>
  29     <refpurpose>List of configured APT data sources</refpurpose>
  30  </refnamediv>
  31
  32  <refsect1><title>Description</title>
  33    <para>
  34       The source list <filename>/etc/apt/sources.list</filename> and the the
  35       files contained in <filename>/etc/apt/sources.list.d/</filename> are
  36       designed to support any number of active sources and a variety of source
  37       media. The files list one source per line (one line style) or contain multiline
  38       stanzas defining one or more sources per stanza (deb822 style), with the
  39       most preferred source listed first (in case a single version is available from more than one source). The information available from the
  40       configured sources is acquired by <command>apt-get update</command> (or
  41       by an equivalent command from another APT front-end).
  42    </para>
  43  </refsect1>
  44
  45  <refsect1><title>sources.list.d</title>
  46     <para>The <filename>/etc/apt/sources.list.d</filename> directory provides
  47        a way to add sources.list entries in separate files.
  48        Two different file formats are allowed as described in the next two sections.
  49        Filenames need to have either the extension <filename>.list</filename> or
  50        <filename>.sources</filename> depending on the contained format.
  51        The filenames may only contain letters (a-z and A-Z),
  52        digits (0-9), underscore (_), hyphen (-) and period (.) characters.
  53        Otherwise APT will print a notice that it has ignored a file, unless that
  54        file matches a pattern in the <literal>Dir::Ignore-Files-Silently</literal>
  55        configuration list - in which case it will be silently ignored.</para>
  56  </refsect1>
  57
  58  <refsect1><title>one line style format</title>
  59     <para>
  60        Files in this format have the extension <filename>.list</filename>.
  61        Each line specifying a source starts with a type (e.g. <literal>deb-src</literal>)
  62        followed by options and arguments for this type.
  63
  64        Individual entries cannot be continued onto a following line. Empty lines
  65        are ignored, and a <literal>#</literal> character anywhere on a line marks
  66        the remainder of that line as a comment. Consequently an entry can be
  67        disabled by commenting out the entire line.
  68
  69        If options should be provided they are separated by spaces and all of
  70        them together are enclosed by square brackets (<literal>[]</literal>)
  71        included in the line after the type separated from it with a space.
  72        If an option allows multiple values these are separated from each other
  73        with a comma (<literal>,</literal>). An option name is separated from its
  74        value(s) by a equal sign (<literal>=</literal>). Multivalue options have
  75        also <literal>-=</literal> and <literal>+=</literal> as separator which
  76        instead of replacing the default with the given value(s) modify the default
  77        value(s) to remove or include the given values.
  78    </para><para>
  79        This is the traditional format and supported by all apt versions.
  80        Note that not all options as described below are supported by all apt versions.
  81        Note also that some older applications parsing this format on its own might not
  82        expect to encounter options as they were uncommon before the introduction of
  83        multi-architecture support.
  84     </para>
  85  </refsect1>
  86
  87  <refsect1><title>deb822 style format</title>
  88     <para>
  89        Files in this format have the extension <filename>.sources</filename>.
  90        The format is similar in syntax to other files used by Debian and its
  91        derivatives, like the metadata itself apt will download from the configured
  92        sources or the <filename>debian/control</filename> file in a Debian source package.
  93
  94        Individual entries are separated by an empty line, additional empty
  95        lines are ignored, and a <literal>#</literal> character at the start of
  96        the line marks the entire line as a comment. An entry can hence be
  97        disabled by commenting out each line belonging to the stanza, but it is
  98        usually easier to add the field "Enabled: no" to the stanza to disable
  99        the entry. Removing the field or setting it to yes reenables it.
 100
 101        Options have the same syntax as every other field: A fieldname separated by
 102        a colon (<literal>:</literal>) and optionally spaces from its value(s).
 103        Note especially that multiple values are separated by spaces, not by
 104        commas as in the one line format. Multivalue fields like <literal>Architectures</literal>
 105        also have <literal>Architectures-Add</literal> and <literal>Architectures-Remove</literal>
 106        to modify the default value rather than replacing it.
 107    </para><para>
 108        This is a new format supported by apt itself since version 1.1. Previous
 109        versions ignore such files with a notice message as described earlier.
 110        It is intended to make this format gradually the default format and
 111        deprecating the previously described one line style format as it is
 112        easier to create, extend and modify by humans and machines alike
 113        especially if a lot of sources and/or options are involved.
 114
 115        Developers who are working with and/or parsing apt sources are highly
 116        encouraged to add support for this format and to contact the APT team
 117        to coordinate and share this work. Users can freely adopt this format
 118        already, but could encounter problems with software not supporting
 119        the format yet.
 120     </para>
 121  </refsect1>
 122
 123  <refsect1><title>The deb and deb-src types: General Format</title>
 124    <para>The <literal>deb</literal> type references a typical two-level Debian
 125    archive, <filename>distribution/component</filename>. The
 126    <literal>distribution</literal> is generally a suite name like
 127    <literal>stable</literal> or <literal>testing</literal> or a codename like
 128    <literal>&stable-codename;</literal> or <literal>&testing-codename;</literal>
 129    while component is one of <literal>main</literal>, <literal>contrib</literal> or
 130    <literal>non-free</literal>. The
 131    <literal>deb-src</literal> type references a Debian distribution's source
 132    code in the same form as the <literal>deb</literal> type.
 133    A <literal>deb-src</literal> line is required to fetch source indexes.</para>
 134
 135    <para>The format for two one line style entries using the
 136    <literal>deb</literal> and <literal>deb-src</literal> types is:</para>
 137
 138    <literallayout>deb [ option1=value1 option2=value2 ] uri suite [component1] [component2] [...]
 139 deb-src [ option1=value1 option2=value2 ] uri suite [component1] [component2] [...]</literallayout>
 140
 141    <para>Alternatively the equivalent entry in deb822 style looks like this:
 142    <literallayout>
 143      Types: deb deb-src
 144      URIs: uri
 145      Suites: suite
 146      Components: [component1] [component2] [...]
 147      option1: value1
 148      option2: value2
 149    </literallayout>
 150    </para>
 151
 152    <para>The URI for the <literal>deb</literal> type must specify the base of the
 153    Debian distribution, from which APT will find the information it needs.
 154    <literal>suite</literal> can specify an exact path, in which case the
 155    components must be omitted and <literal>suite</literal> must end with
 156    a slash (<literal>/</literal>). This is useful for the case when only a
 157    particular sub-directory of the archive denoted by the URI is of interest.
 158    If <literal>suite</literal> does not specify an exact path, at least
 159    one <literal>component</literal> must be present.</para>
 160
 161    <para><literal>suite</literal> may also contain a variable,
 162    <literal>$(ARCH)</literal>
 163    which expands to the Debian architecture (such as <literal>amd64</literal> or
 164    <literal>armel</literal>) used on the system. This permits architecture-independent
 165    <filename>sources.list</filename> files to be used. In general this is only
 166    of interest when specifying an exact path, <literal>APT</literal> will
 167    automatically generate a URI with the current architecture otherwise.</para>
 168
 169    <para>Especially in the one line style format since only one distribution
 170       can be specified per line it may be necessary to have multiple lines for
 171       the same URI, if a subset of all available distributions or components at
 172       that location is desired.  APT will sort the URI list after it has
 173       generated a complete set internally, and will collapse multiple
 174       references to the same Internet host, for instance, into a single
 175       connection, so that it does not inefficiently establish a
 176       connection, close it, do something else, and then re-establish a
 177       connection to that same host. APT also parallelizes connections to
 178       different hosts to more effectively deal with sites with low
 179       bandwidth.</para>
 180
 181    <para>It is important to list sources in order of preference, with the most
 182    preferred source listed first. Typically this will result in sorting
 183    by speed from fastest to slowest (CD-ROM followed by hosts on a local
 184    network, followed by distant Internet hosts, for example).</para>
 185
 186    <para>As an example, the sources for your distribution could look like this
 187       in one line style format:
 188       <literallayout>&sourceslist-list-format;</literallayout> or like this in
 189       deb822 style format:
 190       <literallayout>&sourceslist-sources-format;</literallayout></para>
 191  </refsect1>
 192
 193  <refsect1><title>The deb and deb-src types: Options</title>
 194     <para>Each source entry can have options specified modifying which and how
 195        the source is accessed and data acquired from it. Format, syntax and names
 196        of the options varies between the two formats one line and deb822 style
 197        as described, but they have both the same options available. For simplicity
 198        we list the deb822 fieldname and provide the one line name in brackets.
 199        Remember that beside setting multivalue options explicitly, there is also
 200        the option to modify them based on the default, but we aren't listing those
 201        names explicitly here. Unsupported options are silently ignored by all
 202        APT versions.
 203
 204        <itemizedlist>
 205           <listitem><para><option>Architectures</option>
 206                 (<option>arch</option>) is a multivalue option defining for
 207                 which architectures information should be downloaded. If this
 208                 option isn't set the default is all architectures as defined by
 209                 the <option>APT::Architectures</option> config option.
 210           </para></listitem>
 211
 212           <listitem><para><option>Languages</option>
 213                 (<option>lang</option>) is a multivalue option defining for
 214                 which languages information like translated package
 215                 descriptions should be downloaded.  If this option isn't set
 216                 the default is all languages as defined by the
 217                 <option>Acquire::Languages</option> config option.
 218           </para></listitem>
 219
 220           <listitem><para><option>Targets</option>
 221                 (<option>target</option>) is a multivalue option defining
 222                 which download targets apt will try to acquire from this
 223                 source. If not specified, the default set is defined by the
 224                 <option>Acquire::IndexTargets</option> configuration scope.
 225           </para></listitem>
 226        </itemizedlist>
 227
 228        Further more, there are options which if set effect
 229        <emphasis>all</emphasis> sources with the same URI and Suite, so they
 230        have to be set on all such entries and can not be varied between
 231        different components. APT will try to detect and error out on such
 232        anomalies.
 233
 234        <itemizedlist>
 235           <listitem><para><option>Signed-By</option> (<option>signed-by</option>)
 236                 is either an absolute path to a keyring file (has to be
 237                 accessible and readable for the <literal>_apt</literal> user,
 238                 so ensure everyone has read-permissions on the file) or a
 239                 fingerprint of a key in either the
 240                 <filename>trusted.gpg</filename> keyring or in one of the
 241                 keyrings in the <filename>trusted.gpg.d/</filename> directory
 242                 (see <command>apt-key fingerprint</command>). If the option is
 243                 set only the key(s) in this keyring or only the key with this
 244                 fingerprint is used for the &apt-secure; verification of this
 245                 repository. Otherwise all keys in the trusted keyrings are
 246                 considered valid signers for this repository.
 247           </para></listitem>
 248
 249           <listitem><para><option>Check-Valid-Until</option> (<option>check-valid-until</option>)
 250                 is a yes/no value which controls if APT should try to detect
 251                 replay attacks. A repository creator can declare until then the
 252                 data provided in the repository should be considered valid and
 253                 if this time is reached, but no new data is provided the data
 254                 is considered expired and an error is raised.  Beside
 255                 increasing security as a malicious attacker can't sent old data
 256                 forever denying a user to be able to upgrade to a new version,
 257                 this also helps users identify mirrors which are no longer
 258                 updated. Some repositories like historic archives aren't
 259                 updated anymore by design through, so this check can be
 260                 disabled by setting this option to <literal>no</literal>.
 261                 Defaults to the value of configuration option
 262                 <option>Acquire::Check-Valid-Until</option> which itself
 263                 defaults to <literal>yes</literal>.
 264           </para></listitem>
 265
 266           <listitem><para><option>Valid-Until-Min</option>
 267                 (<option>check-valid-min</option>) and
 268                 <option>Valid-Until-Max</option>
 269                 (<option>valid-until-max</option>) can be used to raise or
 270                 lower the time period in seconds in which the data from this
 271                 repository is considered valid. -Max can be especially useful
 272                 if the repository provides no Valid-Until field on its Release
 273                 file to set your own value, while -Min can be used to increase
 274                 the valid time on seldomly updated (local) mirrors of a more
 275                 frequently updated but less accessible archive (which is in the
 276                 sources.list as well) instead of disabling the check entirely.
 277                 Default to the value of the configuration options
 278                 <option>Acquire::Min-ValidTime</option> and
 279                 <option>Acquire::Max-ValidTime</option> which are both unset by
 280                 default.
 281           </para></listitem>
 282
 283        </itemizedlist>
 284
 285     </para>
 286  </refsect1>
 287
 288  <refsect1><title>URI specification</title>
 289
 290     <para>The currently recognized URI types are:
 291    <variablelist>
 292     <varlistentry><term><command>file</command></term>
 293     <listitem><para>
 294     The file scheme allows an arbitrary directory in the file system to be
 295     considered an archive. This is useful for NFS mounts and local mirrors or
 296     archives.</para></listitem>
 297     </varlistentry>
 298
 299     <varlistentry><term><command>cdrom</command></term>
 300     <listitem><para>
 301     The cdrom scheme allows APT to use a local CD-ROM drive with media
 302     swapping. Use the &apt-cdrom; program to create cdrom entries in the
 303     source list.</para></listitem>
 304     </varlistentry>
 305
 306     <varlistentry><term><command>http</command></term>
 307     <listitem><para>
 308     The http scheme specifies an HTTP server for the archive. If an environment
 309     variable <envar>http_proxy</envar> is set with the format
 310     http://server:port/, the proxy server specified in
 311     <envar>http_proxy</envar> will be used. Users of authenticated
 312     HTTP/1.1 proxies may use a string of the format
 313     http://user:pass@server:port/.
 314     Note that this is an insecure method of authentication.</para></listitem>
 315     </varlistentry>
 316
 317     <varlistentry><term><command>ftp</command></term>
 318     <listitem><para>
 319     The ftp scheme specifies an FTP server for the archive. APT's FTP behavior
 320     is highly configurable; for more information see the
 321     &apt-conf; manual page. Please note that an FTP proxy can be specified
 322     by using the <envar>ftp_proxy</envar> environment variable. It is possible
 323     to specify an HTTP proxy (HTTP proxy servers often understand FTP URLs)
 324     using this environment variable and <emphasis>only</emphasis> this
 325     environment variable. Proxies using HTTP specified in
 326     the configuration file will be ignored.</para></listitem>
 327     </varlistentry>
 328
 329     <varlistentry><term><command>copy</command></term>
 330     <listitem><para>
 331     The copy scheme is identical to the file scheme except that packages are
 332     copied into the cache directory instead of used directly at their location.
 333     This is useful for people using removable media to copy files around with APT.</para></listitem>
 334     </varlistentry>
 335
 336     <varlistentry><term><command>rsh</command></term><term><command>ssh</command></term>
 337     <listitem><para>
 338     The rsh/ssh method invokes RSH/SSH to connect to a remote host and
 339     access the files as a given user. Prior configuration of rhosts or RSA keys
 340     is recommended. The standard <command>find</command> and <command>dd</command>
 341     commands are used to perform the file transfers from the remote host.
 342     </para></listitem>
 343     </varlistentry>
 344
 345     <varlistentry><term>adding more recognizable URI types</term>
 346     <listitem><para>
 347     APT can be extended with more methods shipped in other optional packages, which should
 348     follow the naming scheme <package>apt-transport-<replaceable>method</replaceable></package>.
 349     For instance, the APT team also maintains the package <package>apt-transport-https</package>,
 350     which provides access methods for HTTPS URIs with features similar to the http method.
 351     Methods for using e.g. debtorrent are also available - see &apt-transport-debtorrent;.
 352     </para></listitem>
 353     </varlistentry>
 354   </variablelist>
 355  </para>
 356  </refsect1>
 357
 358  <refsect1><title>Examples</title>
 359    <para>Uses the archive stored locally (or NFS mounted) at /home/apt/debian
 360    for stable/main, stable/contrib, and stable/non-free.</para>
 361    <literallayout>deb file:/home/apt/debian stable main contrib non-free</literallayout>
 362    <literallayout>Types: deb
 363 URIs: file:/home/apt/debian
 364 Suites: stable
 365 Components: main contrib non-free</literallayout>
 366
 367    <para>As above, except this uses the unstable (development) distribution.</para>
 368    <literallayout>deb file:/home/apt/debian unstable main contrib non-free</literallayout>
 369    <literallayout>Types: deb
 370 URIs: file:/home/apt/debian
 371 Suites: unstable
 372 Components: main contrib non-free</literallayout>
 373
 374    <para>Source line for the above</para>
 375    <literallayout>deb-src file:/home/apt/debian unstable main contrib non-free</literallayout>
 376    <literallayout>Types: deb-src
 377 URIs: file:/home/apt/debian
 378 Suites: unstable
 379 Components: main contrib non-free</literallayout>
 380
 381
 382    <para>The first line gets package information for the architectures in <literal>APT::Architectures</literal>
 383    while the second always retrieves <literal>amd64</literal> and <literal>armel</literal>.</para>
 384    <literallayout>deb http://httpredir.debian.org/debian &stable-codename; main
 385 deb [ arch=amd64,armel ] http://httpredir.debian.org/debian &stable-codename; main</literallayout>
 386    <literallayout>Types: deb
 387 URIs: http://httpredir.debian.org/debian
 388 Suites: &stable-codename;
 389 Components: main
 390
 391 Types: deb
 392 URIs: http://httpredir.debian.org/debian
 393 Suites: &stable-codename;
 394 Components: main
 395 Architectures: amd64 armel
 396 </literallayout>
 397
 398    <para>Uses HTTP to access the archive at archive.debian.org, and uses only
 399    the hamm/main area.</para>
 400    <literallayout>deb http://archive.debian.org/debian-archive hamm main</literallayout>
 401    <literallayout>Types: deb
 402 URIs: http://archive.debian.org/debian-archive
 403 Suites: hamm
 404 Components: main</literallayout>
 405
 406    <para>Uses FTP to access the archive at ftp.debian.org, under the debian
 407    directory, and uses only the &stable-codename;/contrib area.</para>
 408    <literallayout>deb ftp://ftp.debian.org/debian &stable-codename; contrib</literallayout>
 409    <literallayout>Types: deb
 410 URIs: ftp://ftp.debian.org/debian
 411 Suites: &stable-codename;
 412 Components: contrib</literallayout>
 413
 414    <para>Uses FTP to access the archive at ftp.debian.org, under the debian
 415    directory, and uses only the unstable/contrib area. If this line appears as
 416    well as the one in the previous example in <filename>sources.list</filename>
 417    a single FTP session will be used for both resource lines.</para>
 418    <literallayout>deb ftp://ftp.debian.org/debian unstable contrib</literallayout>
 419    <literallayout>Types: deb
 420 URIs: ftp://ftp.debian.org/debian
 421 Suites: unstable
 422 Components: contrib</literallayout>
 423
 424    <para>Uses HTTP to access the archive at ftp.tlh.debian.org, under the
 425    universe directory, and uses only files found under
 426    <filename>unstable/binary-i386</filename> on i386 machines,
 427    <filename>unstable/binary-amd64</filename> on amd64, and so
 428    forth for other supported architectures. [Note this example only
 429    illustrates how to use the substitution variable; official debian
 430    archives are not structured like this]
 431    <literallayout>deb http://ftp.tlh.debian.org/universe unstable/binary-$(ARCH)/</literallayout>
 432    <literallayout>Types: deb
 433 URIs: http://ftp.tlh.debian.org/universe
 434 Suites: unstable/binary-$(ARCH)/</literallayout>
 435    </para>
 436
 437    <para>Uses HTTP to get binary packages as well as sources from the stable, testing and unstable
 438       suites and the components main and contrib.</para>
 439    <literallayout>deb http://httpredir.debian.org/debian stable main contrib
 440 deb-src http://httpredir.debian.org/debian stable main contrib
 441 deb http://httpredir.debian.org/debian testing main contrib
 442 deb-src http://httpredir.debian.org/debian testing main contrib
 443 deb http://httpredir.debian.org/debian unstable main contrib
 444 deb-src http://httpredir.debian.org/debian unstable main contrib</literallayout>
 445    <literallayout>Types: deb deb-src
 446 URIs: http://httpredir.debian.org/debian
 447 Suites: stable testing unstable
 448 Components: main contrib
 449 </literallayout>
 450
 451  </refsect1>
 452
 453  <refsect1><title>See Also</title>
 454    <para>&apt-get;, &apt-conf;
 455    </para>
 456  </refsect1>
 457
 458  &manbugs;
 459
 460 </refentry>