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1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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8   Copyright 2014 Lennart Poettering
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23
24 <refentry id="file-hierarchy">
25
26         <refentryinfo>
27                 <title>file-hierarchy</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Lennart</firstname>
34                                 <surname>Poettering</surname>
35                                 <email>lennart@poettering.net</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>file-hierarchy</refentrytitle>
42                 <manvolnum>7</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>file-hierarchy</refname>
47                 <refpurpose>File system hierarchy overview</refpurpose>
48         </refnamediv>
49
50         <refsect1>
51                 <title>Description</title>
52
53                 <para>Operating systems using the
54                 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
55                 system and service manager are organized based on a
56                 file system hierarchy inspired by UNIX, more
57                 specificaly the hierarchy described in the <ulink
58                 url="http://refspecs.linuxfoundation.org/FHS_2.3/fhs-2.3.html">File
59                 System Hierarchy</ulink> specification and
60                 <citerefentry><refentrytitle>hier</refentrytitle><manvolnum>7</manvolnum></citerefentry>. This
61                 manual page describes a more minimal, modernized
62                 subset of these specifications that defines more
63                 strictly the suggestions and restrictions systemd
64                 makes on the file system hierarchy.</para>
65         </refsect1>
66
67         <refsect1>
68                 <title>General Structure</title>
69
70                 <variablelist>
71                         <varlistentry>
72                                 <term><filename>/</filename></term>
73                                 <listitem><para>The file system
74                                 root. Usually writable, but this is
75                                 not required. Possibly a temporary
76                                 file system (<literal>tmpfs</literal>). Not shared with
77                                 other hosts (unless read-only). The
78                                 administrator may create additional
79                                 top-level subdirectories in this tree,
80                                 if required and the name does not
81                                 conflict with any of the directories
82                                 listed below.</para></listitem>
83                         </varlistentry>
84
85                         <varlistentry>
86                                 <term><filename>/boot</filename></term>
87                                 <listitem><para>The boot partition
88                                 used for bringing up the system. On
89                                 EFI systems this is possibly the EFI
90                                 System Partition, also see
91                                 <citerefentry><refentrytitle>systemd-boot-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>. This
92                                 directory is usually strictly local
93                                 the host, and should be considered
94                                 read-only, except when a new kernel or
95                                 boot loader is installed. This
96                                 directory only exists on systems that
97                                 run on physical or emulated hardware
98                                 that requires boot
99                                 loaders.</para></listitem>
100                         </varlistentry>
101
102                         <varlistentry>
103                                 <term><filename>/etc</filename></term>
104                                 <listitem><para>System-specific
105                                 configuration. This directory may or
106                                 may not be read-only. Frequently, this
107                                 directory is pre-populated with
108                                 vendor-supplied configuration files,
109                                 but applications should not make
110                                 assumptions about this directory
111                                 being fully populated or populated at
112                                 all, and should fall back to defaults
113                                 if configuration is missing.</para></listitem>
114                         </varlistentry>
115
116                         <varlistentry>
117                                 <term><filename>/home</filename></term>
118                                 <listitem><para>The location for
119                                 normal user's home
120                                 directories. Possibly shared with
121                                 other systems, and never
122                                 read-only. This directory should only
123                                 be used for normal users, never for
124                                 system users. This directory and
125                                 possibly the directories contained
126                                 within it might only become available
127                                 or writable in late boot or even on
128                                 user login only. This directory might
129                                 be placed on limited-functionality
130                                 network file systems, hence
131                                 applications should not assume the
132                                 full set of file API is available on
133                                 this directory. Applications should
134                                 generally not reference this directory
135                                 directly, but via the per-user
136                                 <varname>$HOME</varname> environment
137                                 variable, or via the home directory
138                                 field of the user
139                                 database.</para></listitem>
140                         </varlistentry>
141
142                         <varlistentry>
143                                 <term><filename>/root</filename></term>
144                                 <listitem><para>The home directory of
145                                 the root user. The root user's home
146                                 directory is located outside of
147                                 <filename>/home</filename> in order to
148                                 make sure the root user may log in
149                                 even without <filename>/home</filename>
150                                 being available and
151                                 mounted.</para></listitem>
152                         </varlistentry>
153
154                         <varlistentry>
155                                 <term><filename>/srv</filename></term>
156                                 <listitem><para>The place to store
157                                 general server payload, managed by the
158                                 administrator. No restrictions are
159                                 made how this directory is organized
160                                 internally. Generally writable, and
161                                 possibly shared among systems. This
162                                 directory might become available or
163                                 writable only very late during
164                                 boot.</para></listitem>
165                         </varlistentry>
166
167                         <varlistentry>
168                                 <term><filename>/tmp</filename></term>
169                                 <listitem><para>The place for small
170                                 temporary files. This directory is
171                                 usually mounted as
172                                 <literal>tmpfs</literal> instance, and
173                                 should hence not be used for larger
174                                 files. (Use
175                                 <filename>/var/tmp</filename> for
176                                 larger files.) Since the directory is
177                                 accessible to other users of the
178                                 system it is essential that this
179                                 directory is only written to with the
180                                 <citerefentry><refentrytitle>mkstemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
181                                 <citerefentry><refentrytitle>mkdtemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>
182                                 and related calls. This directory is
183                                 usually flushed at boot-up. Also,
184                                 files that are not accessed within a
185                                 certain time are usually automatically
186                                 deleted. If applications find the
187                                 environment variable
188                                 <varname>$TMP</varname> set they
189                                 should prefer using the directory
190                                 specified in it over directly
191                                 referencing
192                                 <filename>/tmp</filename>.</para></listitem>
193                         </varlistentry>
194
195                 </variablelist>
196         </refsect1>
197
198         <refsect1>
199                 <title>Runtime Data</title>
200
201                 <variablelist>
202                         <varlistentry>
203                                 <term><filename>/run</filename></term>
204                                 <listitem><para>A
205                                 <literal>tmpfs</literal> file system
206                                 for system packages to place runtime
207                                 data in. This directory is flushed on
208                                 boot, and generally writable for
209                                 priviliged programs
210                                 only. Always writable.</para></listitem>
211                         </varlistentry>
212
213                         <varlistentry>
214                                 <term><filename>/run/log</filename></term>
215                                 <listitem><para>Runtime system
216                                 logs. System components may place
217                                 private logs in this directory. Always
218                                 writable, even when
219                                 <filename>/var/log</filename> might
220                                 not be accessible
221                                 yet.</para></listitem>
222                         </varlistentry>
223
224                         <varlistentry>
225                                 <term><filename>/run/user</filename></term>
226                                 <listitem><para>Contains per-user
227                                 runtime directories, each usually
228                                 invidually mounted
229                                 <literal>tmpfs</literal>
230                                 instances. Always writable, flushed at
231                                 each reboot and when the user logs
232                                 out. User code should not reference
233                                 this directory directly, but via the
234                                 <varname>$XDG_RUNTIME_DIR</varname>
235                                 environment variable, as documented in
236                                 the <ulink
237                                 url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
238                                 Base Directory
239                                 Specification</ulink>.</para></listitem>
240                         </varlistentry>
241                 </variablelist>
242         </refsect1>
243
244         <refsect1>
245                 <title>Vendor-supplied Operating System Resources</title>
246
247                 <variablelist>
248
249                         <varlistentry>
250                                 <term><filename>/usr</filename></term>
251                                 <listitem><para>Vendor-supplied
252                                 operating system resources. Usually
253                                 read-only, but this is not
254                                 required. Possibly shared between
255                                 multiple hosts. This directory should
256                                 not be modified by the administrator,
257                                 except when installing or removing
258                                 vendor-supplied
259                                 packages.</para></listitem>
260                         </varlistentry>
261
262                         <varlistentry>
263                                 <term><filename>/usr/bin</filename></term>
264                                 <listitem><para>Binaries for user
265                                 commands, that shall appear in the
266                                 <varname>$PATH</varname> search
267                                 path. It is recommended not to place
268                                 binaries in this directory that are
269                                 not useful for invocation from a shell
270                                 (such as daemon binaries); these
271                                 should be placed in a subdirectory of
272                                 <filename>/usr/lib</filename>
273                                 instead.</para></listitem>
274                         </varlistentry>
275
276                         <varlistentry>
277                                 <term><filename>/usr/include</filename></term>
278                                 <listitem><para>C and C++ API header
279                                 files of system
280                                 libraries.</para></listitem>
281                         </varlistentry>
282
283                         <varlistentry>
284                                 <term><filename>/usr/lib</filename></term>
285                                 <listitem><para>System libraries and
286                                 package-specific
287                                 data.</para></listitem>
288                         </varlistentry>
289
290                         <varlistentry>
291                                 <term><filename>/usr/lib64</filename></term>
292                                 <listitem><para>Secondary library
293                                 directory for placing 64bit versions
294                                 of system libraries in, if the primary
295                                 architecture of the system is 32bit,
296                                 and <filename>/usr/lib64</filename> is
297                                 defined in the platform ABI. This
298                                 directory should not be used for
299                                 package-specific data, unless this
300                                 data requires 64bit-specific versions,
301                                 too.</para></listitem>
302                         </varlistentry>
303
304                         <varlistentry>
305                                 <term><filename>/usr/share</filename></term>
306                                 <listitem><para>Resources shared
307                                 betwen multiple packages, such as
308                                 documentation, man pages, time zone
309                                 information, fonts and other
310                                 resources. Usually, the precise
311                                 location and format of files stored
312                                 below this directory is subject to
313                                 specifications that ensure
314                                 interoperability.</para></listitem>
315                         </varlistentry>
316
317                         <varlistentry>
318                                 <term><filename>/usr/share/doc</filename></term>
319                                 <listitem><para>Documentation for the
320                                 operating system or system
321                                 packages.</para></listitem>
322                         </varlistentry>
323
324                         <varlistentry>
325                                 <term><filename>/usr/share/factory/etc</filename></term>
326                                 <listitem><para>Repository for
327                                 vendor-supplied default configuration
328                                 files. This directory should be
329                                 populated with pristine vendor versions
330                                 of all configuration files that may be
331                                 placed in
332                                 <filename>/etc</filename>. This is
333                                 useful to compare the local
334                                 configuration of a system with vendor
335                                 defaults and to populate the local
336                                 configuration with
337                                 defaults.</para></listitem>
338                         </varlistentry>
339
340                         <varlistentry>
341                                 <term><filename>/usr/share/factory/var</filename></term>
342
343                                 <listitem><para>Similar to
344                                 <filename>/usr/share/factory/etc</filename>
345                                 but for vendor versions of files in
346                                 the variable, persistent data
347                                 directory
348                                 <filename>/var</filename>.</para></listitem>
349
350                         </varlistentry>
351                 </variablelist>
352         </refsect1>
353
354         <refsect1>
355                 <title>Persistent Variable System Data</title>
356
357                 <variablelist>
358                         <varlistentry>
359                                 <term><filename>/var</filename></term>
360                                 <listitem><para>Persistent, variable
361                                 system data. Must be writable. This
362                                 directory might be pre-populated with
363                                 vendor-supplied data, but applications
364                                 should be able to reconstruct
365                                 necessary files and directories in
366                                 this subhierarchy should they be
367                                 missing, as the system might start up
368                                 without this directory being
369                                 populated. Persistency is recommended,
370                                 but optional, to support ephemeral
371                                 systems. This directory might become
372                                 available or writable only very late
373                                 during boot. Components that are
374                                 required to operate during early boot
375                                 hence shall not unconditionally rely
376                                 on this directory.</para></listitem>
377                         </varlistentry>
378
379                         <varlistentry>
380                                 <term><filename>/var/cache</filename></term>
381                                 <listitem><para>Persistent system
382                                 cache data. System components may
383                                 place non-essential data in this
384                                 directory. Flushing this directory
385                                 should have no effect on operation of
386                                 programs, except for increased
387                                 runtimes necessary to rebuild these
388                                 caches.</para></listitem>
389                         </varlistentry>
390
391                         <varlistentry>
392                                 <term><filename>/var/lib</filename></term>
393                                 <listitem><para>Persistent system
394                                 data. System components may
395                                 place private data in this
396                                 directory.</para></listitem>
397                         </varlistentry>
398
399                         <varlistentry>
400                                 <term><filename>/var/log</filename></term>
401                                 <listitem><para>Persistent system
402                                 logs. System components may place
403                                 private logs in this directory, though
404                                 it is recommended to do most logging
405                                 via the
406                                 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
407                                 and
408                                 <citerefentry><refentrytitle>sd_journal_print</refentrytitle><manvolnum>3</manvolnum></citerefentry>
409                                 calls.</para></listitem>
410                         </varlistentry>
411
412                         <varlistentry>
413                                 <term><filename>/var/spool</filename></term>
414                                 <listitem><para>Persistent system
415                                 spool data, such as printer or mail
416                                 queues.</para></listitem>
417                         </varlistentry>
418
419                         <varlistentry>
420                                 <term><filename>/var/tmp</filename></term>
421                                 <listitem><para>The place for larger
422                                 and persistent temporary files. In
423                                 contrast to <filename>/tmp</filename>
424                                 this directory is usually mounted from
425                                 a persistent physical file system and
426                                 can thus accept larger files. (Use
427                                 <filename>/tmp</filename> for smaller
428                                 files.) This directory is generally
429                                 not flushed at boot-up, but time-based
430                                 cleanup of files that have not been
431                                 accessed for a certain time is
432                                 applied. The same security
433                                 restrictions as with
434                                 <filename>/tmp</filename> apply, and
435                                 hence only
436                                 <citerefentry><refentrytitle>mkstemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
437                                 <citerefentry><refentrytitle>mkdtemp</refentrytitle><manvolnum>3</manvolnum></citerefentry>
438                                 or similar calls should be used to
439                                 make use of this directory. If
440                                 applications find the environment
441                                 variable <varname>$TMP</varname> set
442                                 they should prefer using the directory
443                                 specified in it over directly
444                                 referencing
445                                 <filename>/var/tmp</filename>.
446                                 </para></listitem>
447                         </varlistentry>
448
449                 </variablelist>
450         </refsect1>
451
452         <refsect1>
453                 <title>Virtual Kernel and API File Systems</title>
454
455                 <variablelist>
456                         <varlistentry>
457                                 <term><filename>/dev</filename></term>
458                                 <listitem><para>The root directory for
459                                 device nodes. Usually this directory
460                                 is mounted as
461                                 <literal>devtmpfs</literal> instance,
462                                 but might be of a different type in
463                                 sandboxed/containerized setups. This
464                                 directory is managed jointly by the
465                                 kernel and
466                                 <citerefentry><refentrytitle>systemd-udevd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
467                                 and should not be written to by other
468                                 components. A number of special
469                                 purpose virtual file systems might be
470                                 mounted below this
471                                 directory.</para></listitem>
472                         </varlistentry>
473
474                         <varlistentry>
475                                 <term><filename>/dev/shm</filename></term>
476                                 <listitem><para>Place for POSIX shared
477                                 memory segments, as created via
478                                 <citerefentry><refentrytitle>shm_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>. This
479                                 directory is flushed on boot, and is a
480                                 <literal>tmpfs</literal> file
481                                 system. Since all users have write
482                                 access to this directory, special care
483                                 should be taken to avoid name clashes
484                                 and vulnerabilities. For normal users,
485                                 shared memory segments in this
486                                 directory are usually deleted when the
487                                 user logs out. Usually it is a better
488                                 idea to use memory mapped files in
489                                 <filename>/run</filename> (for system
490                                 programs) or
491                                 <varname>$XDG_RUNTIME_DIR</varname>
492                                 (for user programs) instead of POSIX
493                                 shared memory segments, since they
494                                 directories are not world-writable and
495                                 hence not vulnerable to
496                                 security-sensitive name
497                                 clashes.</para></listitem>
498                         </varlistentry>
499
500                         <varlistentry>
501                                 <term><filename>/proc</filename></term>
502                                 <listitem><para>A virtual kernel file
503                                 system exposing the process list and
504                                 other functionality. This file system
505                                 is mostly an API to interface with the
506                                 kernel and not a place where normal
507                                 files may be stored. For details, see
508                                 <citerefentry><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>. A
509                                 number of special purpose virtual file
510                                 systems might be mounted below this
511                                 directory.</para></listitem>
512                         </varlistentry>
513
514                         <varlistentry>
515                                 <term><filename>/proc/sys</filename></term>
516                                 <listitem><para>A hierarchy below
517                                 <filename>/proc</filename> that
518                                 exposes a number of kernel
519                                 tunables. The primary way to configure
520                                 the settings in this API file tree is
521                                 via
522                                 <citerefentry><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
523                                 files. In sandboxed/containerized
524                                 setups this directory is generally
525                                 mounted read-only.</para></listitem>
526                         </varlistentry>
527
528                         <varlistentry>
529                                 <term><filename>/sys</filename></term>
530                                 <listitem><para>A virtual kernel file
531                                 system exposing discovered devices and
532                                 other functionality. This file system
533                                 is mostly an API to interface with the
534                                 kernel and not a place where normal
535                                 files may be stored. In
536                                 sandboxed/containerized setups this
537                                 directory is generally mounted
538                                 read-only. A number of special purpose
539                                 virtual file systems might be mounted
540                                 below this
541                                 directory.</para></listitem>
542                         </varlistentry>
543
544
545                 </variablelist>
546         </refsect1>
547
548         <refsect1>
549                 <title>Compatibility Symlinks</title>
550
551                 <variablelist>
552                         <varlistentry>
553                                 <term><filename>/bin</filename></term>
554                                 <term><filename>/sbin</filename></term>
555                                 <term><filename>/usr/sbin</filename></term>
556
557                                 <listitem><para>These compatibility
558                                 symlinks point to
559                                 <filename>/usr/bin</filename>,
560                                 ensuring that scripts and binaries
561                                 referencing these legacy paths
562                                 correctly find their binaries.</para></listitem>
563                         </varlistentry>
564
565                         <varlistentry>
566                                 <term><filename>/lib</filename></term>
567
568                                 <listitem><para>This compatibility
569                                 symlink points to
570                                 <filename>/usr/lib</filename>,
571                                 ensuring that binaries referencing
572                                 this legacy path correctly find
573                                 their libraries.</para></listitem>
574                         </varlistentry>
575
576                         <varlistentry>
577                                 <term><filename>/lib64</filename></term>
578
579                                 <listitem><para>This compatibility
580                                 symlink points to
581                                 <filename>/usr/lib64</filename>,
582                                 ensuring that binaries referencing
583                                 this legacy path correctly find their
584                                 libraries. This symlink only exists on
585                                 architectures whose ABI requires a
586                                 64bit version of the library
587                                 directory.</para></listitem>
588                         </varlistentry>
589
590                         <varlistentry>
591                                 <term><filename>/var/run</filename></term>
592
593                                 <listitem><para>This compatibility
594                                 symlink points to
595                                 <filename>/run</filename>, ensuring
596                                 that programs referencing this legacy
597                                 path correctly find their runtime
598                                 data.</para></listitem>
599                         </varlistentry>
600
601                 </variablelist>
602         </refsect1>
603
604         <refsect1>
605                 <title>System Packages</title>
606
607                 <para>Developers of system packages should follow
608                 strict rules when placing their own files in the file
609                 system. The following table lists recommended
610                 locations for specific types of files.</para>
611
612                 <table>
613                   <title>System Package Data Location</title>
614                   <tgroup cols='2' align='left' colsep='1' rowsep='1'>
615                     <colspec colname="directory" />
616                     <colspec colname="purpose" />
617                     <thead>
618                       <row>
619                         <entry>Directory</entry>
620                         <entry>Purpose</entry>
621                       </row>
622                     </thead>
623                     <tbody>
624                       <row>
625                         <entry><filename>/usr/bin</filename></entry>
626                         <entry>Package executables that shall appear in the <varname>$PATH</varname> executable search path. It is not recommended to place internal binaries or binaries that are not commonly invoked from the shell in this directory, such as daemon binaries. As this directory is shared with most other packages of the system special care should be take to pick unique names for files placed here, that are unlikely to clash with other package's files.</entry>
627                       </row>
628                       <row>
629                         <entry><filename>/usr/lib</filename></entry>
630                         <entry>Public shared libraries of the package, compiled for the primary architecture of the operating system. As above, be careful with using too generic names, and pick unique names for your libraries to place here to avoid name clashes.</entry>
631                       </row>
632                       <row>
633                         <entry><filename>/usr/lib/<replaceable>package</replaceable></filename></entry>
634                         <entry>Private other vendor resources of the package, including private binaries and libraries, but also including any other kind of read-only vendor data.</entry>
635                       </row>
636                       <row>
637                         <entry><filename>/usr/lib64</filename></entry>
638                         <entry>Public shared libraries of the package, compiled for the secondary, 64bit architecture, if this is part of the platform ABI of the architecture.</entry>
639                       </row>
640                       <row>
641                         <entry><filename>/usr/lib64/<replaceable>package</replaceable></filename></entry>
642                         <entry>Private other vendor resources of the package that are architecture-specific and cannot be shared between primary and secondary architectures. Note that this generally does not include private binaries since binaries of the primary architecture may generally be invoked from secondary architecture code just fine.</entry>
643                       </row>
644                       <row>
645                         <entry><filename>/usr/include/<replaceable>package</replaceable></filename></entry>
646                         <entry>Public C/C++ APIs of public shared libraries of the package.</entry>
647                       </row>
648                       <row>
649                         <entry><filename>/etc/<replaceable>package</replaceable></filename></entry>
650                         <entry>System-specific configuration for the package. It is recommended to default to safe fallbacks if this configuration is missing, if this is possible. Alternatively, a <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> fragment may be used to copy or symlink the necessary files and directores from <filename>/usr/share/factory</filename> during boot, via the <literal>L</literal> or <literal>C</literal> directives.</entry>
651                       </row>
652                       <row>
653                         <entry><filename>/run/<replaceable>package</replaceable></filename></entry>
654                         <entry>Runtime data for the package. Packages must be able to create the necessary subdirectories in this tree on their own, since the directory is flushed automatically on boot. Alternatively, a <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> fragment may be used to create the necessary directories during boot.</entry>
655                       </row>
656                       <row>
657                         <entry><filename>/run/log/<replaceable>package</replaceable></filename></entry>
658                         <entry>Runtime log data for the package.</entry>
659                       </row>
660                       <row>
661                         <entry><filename>/var/cache/<replaceable>package</replaceable></filename></entry>
662                         <entry>Persistent cache data of the package. If this directory is flushed the application should work correctly on next invocation, though possibly slowed done due to the need to rebuild any local cache files.</entry>
663                       </row>
664                       <row>
665                         <entry><filename>/var/lib/<replaceable>package</replaceable></filename></entry>
666                         <entry>Persistent private data of the package. This is the primary place to put persistent data that does not fall into the other categories listed. Packages should be able to create the necessary subdirectories in this tree on their own, since the directory might be missing on boot. Alternatively, a <citerefentry><refentrytitle>tmpfiles.d</refentrytitle><manvolnum>5</manvolnum></citerefentry> fragment may be used to create the necessary directories during boot.</entry>
667                       </row>
668                       <row>
669                         <entry><filename>/var/log/<replaceable>package</replaceable></filename></entry>
670                         <entry>Persistent log data of the package.</entry>
671                       </row>
672                       <row>
673                         <entry><filename>/var/spool/<replaceable>package</replaceable></filename></entry>
674                         <entry>Persistent spool/queue data of the package.</entry>
675                       </row>
676                     </tbody>
677                   </tgroup>
678                 </table>
679         </refsect1>
680
681         <refsect1>
682                 <title>See Also</title>
683                 <para>
684                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
685                         <citerefentry><refentrytitle>hier</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
686                         <citerefentry><refentrytitle>systemd-boot-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
687                         <citerefentry><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
688                 </para>
689         </refsect1>
690
691 </refentry>