1APT.CONF(5) APT.CONF(5)
2
6 apt.conf - Configuration file for APT
7
9 apt.conf is the main configuration file for the APT suite of tools, all
10 tools make use of the configuration file and a common command line
11 parser to provide a uniform environment. When an APT tool starts up it
12 will read the configuration specified by the APT_CONFIG environment
13 variable (if any) and then read the files in Dir::Etc::Parts then read
14 the main configuration file specified by Dir::Etc::main then finally
15 apply the command line options to override the configuration direc‐
16 tives, possibly loading even more config files.
17 The configuration file is organized in a tree with options organized
19 into functional groups. Option specification is given with a double
20 colon notation, for instance APT::Get::Assume-Yes is an option within
21 the APT tool group, for the Get tool. Options do not inherit from their
22 parent groups.
23 Syntacticly the configuration language is modeled after what the ISC
25 tools such as bind and dhcp use. Lines starting with // are treated as
26 comments (ignored). Each line is of the form
27 APT::Get::Assume-Yes "true";
29 The trailing semicolon is required and the quotes are optional. A new
30 scope can be opened with curly braces, like:
31 APT {
33 Get {
34 Assume-Yes "true";
35 Fix-Broken "true";
36 };
37 };
38 with newlines placed to make it more readable. Lists can be created by
39 opening a scope and including a single word enclosed in quotes followed
40 by a semicolon. Multiple entries can be included, each separated by a
41 semicolon.
42 DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
44 In general the sample configuration file in
46 /usr/share/doc/apt-0.5.15lorg3.2/examples/apt.conf
47 /usr/share/doc/apt-0.5.15lorg3.2/examples/configure-index is a good
48 guide for how it should look.
49 Two specials are allowed, #include and #clear. #include will include
51 the given file, unless the filename ends in a slash, then the whole
52 directory is included. #clear is used to erase a list of names.
53 All of the APT tools take a -o option which allows an arbitrary config‐
55 uration directive to be specified on the command line. The syntax is a
56 full option name (APT::Get::Assume-Yes for instance) followed by an
57 equals sign then the new value of the option. Lists can be appended too
58 by adding a trailing :: to the list name.
59
61 This group of options controls general APT behavior as well as holding
62 the options for all of the tools.
63 Architecture
65 System Architecture; sets the architecture to use when fetching
66 files and parsing package lists. The internal default is the
67 architecture apt was compiled for.
68 Ignore-Hold
70 Ignore Held packages; This global option causes the problem
71 resolver to ignore held packages in its decision making.
72 Clean-Installed
74 Defaults to on. When turned on the autoclean feature will remove
75 any packages which can no longer be downloaded from the cache.
76 If turned off then packages that are locally installed are also
77 excluded from cleaning - but note that APT provides no direct
78 means to reinstall them.
79 Immediate-Configure
81 Disable Immediate Configuration; This dangerous option disables
82 some of APT's ordering code to cause it to make fewer dpkg
83 calls. Doing so may be necessary on some extremely slow single
84 user systems but is very dangerous and may cause package install
85 scripts to fail or worse. Use at your own risk.
86 Force-LoopBreak
88 Never Enable this option unless you -really- know what you are
89 doing. It permits APT to temporarily remove an essential package
90 to break a Conflicts/Conflicts or Conflicts/Pre-Depend loop
91 between two essential packages. SUCH A LOOP SHOULD NEVER EXIST
92 AND IS A GRAVE BUG. This option will work if the essential pack‐
93 ages are not tar, gzip, libc, dpkg, bash or anything that those
94 packages depend on.
95 Cache-Limit
97 APT uses a fixed size memory mapped cache file to store the
98 'available' information. This sets the size of that cache.
99 Build-Essential
101 Defines which package(s) are considered essential build depen‐
102 dencies.
103 Get The Get subsection controls the apt-get(8) tool, please see its
105 documentation for more information about the options here.
106 Cache The Cache subsection controls the apt-cache(8) tool, please see
108 its documentation for more information about the options here.
109 CDROM The CDROM subsection controls the apt-cdrom(8) tool, please see
111 its documentation for more information about the options here.
112
114 The Acquire group of options controls the download of packages and the
115 URI handlers.
116 Queue-Mode
118 Queuing mode; Queue-Mode can be one of host or access which
119 determines how APT parallelizes outgoing connections. host
120 means that one connection per target host will be opened, access
121 means that one connection per URI type will be opened.
122 Retries
124 Number of retries to perform. If this is non-zero APT will retry
125 failed files the given number of times.
126 Source-Symlinks
128 Use symlinks for source archives. If set to true then source ar‐
129 chives will be symlinked when possible instead of copying. True
130 is the default
131 http HTTP URIs; http::Proxy is the default http proxy to use. It is
133 in the standard form of http://[[user][:pass]@]host[:port]/. Per
134 host proxies can also be specified by using the form
135 http::Proxy::<host> with the special keyword DIRECT meaning to
136 use no proxies. The http_proxy environment variable will over‐
137 ride all settings.
138 Three settings are provided for cache control with HTTP/1.1 com‐
140 pliant proxy caches. No-Cache tells the proxy to not use its
141 cached response under any circumstances, Max-Age is sent only
142 for index files and tells the cache to refresh its object if it
143 is older than the given number of seconds. Debian updates its
144 index files daily so the default is 1 day. No-Store specifies
145 that the cache should never store this request, it is only set
146 for archive files. This may be useful to prevent polluting a
147 proxy cache with very large .deb files. Note: Squid 2.0.2 does
148 not support any of these options.
149 The option timeout sets the timeout timer used by the method,
151 this applies to all things including connection timeout and data
152 timeout.
153 One setting is provided to control the pipeline depth in cases
155 where the remote server is not RFC conforming or buggy (such as
156 Squid 2.0.2) Acquire::http::Pipeline-Depth can be a value from 0
157 to 5 indicating how many outstanding requests APT should send. A
158 value of zero MUST be specified if the remote host does not
159 properly linger on TCP connections - otherwise data corruption
160 will occur. Hosts which require this are in violation of RFC
161 2068.
162 ftp FTP URIs; ftp::Proxy is the default proxy server to use. It is
164 in the standard form of ftp://[[user][:pass]@]host[:port]/ and
165 is overridden by the ftp_proxy environment variable. To use a
166 ftp proxy you will have to set the ftp::ProxyLogin script in the
167 configuration file. This entry specifies the commands to send to
168 tell the proxy server what to connect to. Please see
169 /usr/share/doc/apt-0.5.15lorg3.2/examples/configure-index for an
170 example of how to do this. The subsitution variables available
171 are $(PROXY_USER), $(PROXY_PASS), $(SITE_USER), $(SITE_PASS),
172 $(SITE), and $(SITE_PORT). Each is taken from it's respective
173 URI component.
174 The option timeout sets the timeout timer used by the method,
176 this applies to all things including connection timeout and data
177 timeout.
178 Several settings are provided to control passive mode. Generally
180 it is safe to leave passive mode on, it works in nearly every
181 environment. However some situations require that passive mode
182 be disabled and port mode ftp used instead. This can be done
183 globally, for connections that go through a proxy or for a spe‐
184 cific host (See the sample config file for examples)
185 It is possible to proxy FTP over HTTP by setting the ftp_proxy
187 environment variable to a http url - see the discussion of the
188 http method above for syntax. You cannot set this in the config‐
189 uration file and it is not recommended to use FTP over HTTP due
190 to its low efficiency.
191 The setting ForceExtended controls the use of RFC2428 EPSV and
193 EPRT commands. The defaut is false, which means these commands
194 are only used if the control connection is IPv6. Setting this to
195 true forces their use even on IPv4 connections. Note that most
196 FTP servers do not support RFC2428.
197 cdrom CDROM URIs; the only setting for CDROM URIs is the mount point,
199 cdrom::Mount which must be the mount point for the CDROM drive
200 as specified in /etc/fstab. It is possible to provide alternate
201 mount and unmount commands if your mount point cannot be listed
202 in the fstab (such as an SMB mount and old mount packages). The
203 syntax is to put
204 "/cdrom/"::Mount "foo";
206 within the cdrom block. It is important to have the trailing
207 slash. Unmount commands can be specified using UMount.
208
210 The Dir::State section has directories that pertain to local state
211 information. lists is the directory to place downloaded package lists
212 in and status is the name of the dpkg status file. preferences is the
213 name of the APT preferences file. Dir::State contains the default
214 directory to prefix on all sub items if they do not start with / or ./.
215 Dir::Cache contains locations pertaining to local cache information,
217 such as the two package caches srcpkgcache and pkgcache as well as the
218 location to place downloaded archives, Dir::Cache::archives. Generation
219 of caches can be turned off by setting their names to be blank. This
220 will slow down startup but save disk space. It is probably prefered to
221 turn off the pkgcache rather than the srcpkgcache. Like Dir::State the
222 default directory is contained in Dir::Cache
223 Dir::Etc contains the location of configuration files, sourcelist gives
225 the location of the sourcelist and main is the default configuration
226 file (setting has no effect, unless it is done from the config file
227 specified by APT_CONFIG).
228 The Dir::Parts setting reads in all the config fragments in lexical
230 order from the directory specified. After this is done then the main
231 config file is loaded.
232 Binary programs are pointed to by Dir::Bin. Dir::Bin::Methods specifies
234 the location of the method handlers and gzip, dpkg, apt-get, dpkg-
235 source, dpkg-buildpackage and apt-cache specify the location of the
236 respective programs.
237
239 When APT is used as a dselect(8) method several configuration direc‐
240 tives control the default behaviour. These are in the DSelect section.
241 Clean Cache Clean mode; this value may be one of always, prompt, auto,
243 pre-auto and never. always and prompt will remove all packages
244 from the cache after upgrading, prompt (the default) does so
245 conditionally. auto removes only those packages which are no
246 longer downloadable (replaced with a new version for instance).
247 pre-auto performs this action before downloading new packages.
248 Options
250 The contents of this variable is passed to apt-get(8) as command
251 line options when it is run for the install phase.
252 UpdateOptions
254 The contents of this variable is passed to apt-get(8) as command
255 line options when it is run for the update phase.
256 PromptAfterUpdate
258 If true the [U]pdate operation in dselect(8) will always prompt
259 to continue. The default is to prompt only on error.
260
262 Several configuration directives control how APT invokes dpkg(8). These
263 are in the DPkg section.
264 Options
266 This is a list of options to pass to dpkg. The options must be
267 specified using the list notation and each list item is passed
268 as a single argument to dpkg(8).
269 Pre-Invoke
271 Post-Invoke
273 This is a list of shell commands to run before/after invoking
274 dpkg(8). Like Options this must be specified in list notation.
275 The commands are invoked in order using /bin/sh, should any fail
276 APT will abort.
277 Pre-Install-Pkgs
279 This is a list of shell commands to run before invoking dpkg.
280 Like Options this must be specified in list notation. The com‐
281 mands are invoked in order using /bin/sh, should any fail APT
282 will abort. APT will pass to the commands on standard input the
283 filenames of all .deb files it is going to install, one per
284 line.
285 Version 2 of this protocol dumps more information, including the
287 protocol version, the APT configuration space and the packages,
288 files and versions being changed. Version 2 is enabled by set‐
289 ting DPkg::Tools::Options::cmd::Version to 2. cmd is a command
290 given to Pre-Install-Pkgs.
291 Run-Directory
293 APT chdirs to this directory before invoking dpkg, the default
294 is /.
295 Build-Options
297 These options are passed to dpkg-buildpackage(1) when compiling
298 packages, the default is to disable signing and produce all
299 binaries.
300
302 Most of the options in the debug section are not interesting to the
303 normal user, however Debug::pkgProblemResolver shows interesting output
304 about the decisions dist-upgrade makes. Debug::NoLocking disables file
305 locking so APT can do some operations as non-root and Debug::pkgDPkgPM
306 will print out the command line for each dpkg invokation.
307 Debug::IdentCdrom will disable the inclusion of statfs data in CDROM
308 IDs.
309
311 /usr/share/doc/apt-0.5.15lorg3.2/examples/configure-index contains a
312 sample configuration file showing the default values for all possible
313 options.
314
316 /etc/apt/apt.conf
317
319 apt-cache(8), apt-config(8), apt_preferences(5).
320
322 See the APT bug page <URL:http://bugs.debian.org/src:apt>. If you wish
323 to report a bug in APT, please see /usr/share/doc/debian/bug-report‐
324 ing.txt or the reportbug(1) command.
325
327 APT was written by the APT team <apt@packages.debian.org>.
328 02 August 2007 APT.CONF(5)