man/journald.conf.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
   3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   4         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   5
   6 <!--
   7   This file is part of systemd.
   8
   9   Copyright 2010 Lennart Poettering
  10
  11   systemd is free software; you can redistribute it and/or modify it
  12   under the terms of the GNU Lesser General Public License as published by
  13   the Free Software Foundation; either version 2.1 of the License, or
  14   (at your option) any later version.
  15
  16   systemd is distributed in the hope that it will be useful, but
  17   WITHOUT ANY WARRANTY; without even the implied warranty of
  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19   Lesser General Public License for more details.
  20
  21   You should have received a copy of the GNU Lesser General Public License
  22   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  23 -->
  24
  25 <refentry id="journald.conf">
  26         <refentryinfo>
  27                 <title>journald.conf</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>journald.conf</refentrytitle>
  42                 <manvolnum>5</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>journald.conf</refname>
  47                 <refpurpose>Journal service configuration file</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename>/etc/systemd/journald.conf</filename></para>
  52         </refsynopsisdiv>
  53
  54         <refsect1>
  55                 <title>Description</title>
  56
  57                 <para>This file configures various parameters of the
  58                 systemd journal service,
  59                 <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
  60
  61         </refsect1>
  62
  63         <refsect1>
  64                 <title>Options</title>
  65
  66                 <para>All options are configured in the
  67                 <literal>[Journal]</literal> section:</para>
  68
  69                 <variablelist>
  70
  71                         <varlistentry>
  72                                 <term><varname>Storage=</varname></term>
  73
  74                                 <listitem><para>Controls where to
  75                                 store journal data. One of
  76                                 <literal>volatile</literal>,
  77                                 <literal>persistent</literal>,
  78                                 <literal>auto</literal> and
  79                                 <literal>none</literal>. If
  80                                 <literal>volatile</literal>, journal
  81                                 log data will be stored only in
  82                                 memory, i.e. below the
  83                                 <filename>/run/log/journal</filename>
  84                                 hierarchy (which is created if
  85                                 needed). If
  86                                 <literal>persistent</literal>, data will
  87                                 be stored preferably on disk,
  88                                 i.e. below the
  89                                 <filename>/var/log/journal</filename>
  90                                 hierarchy (which is created if
  91                                 needed), with a fallback to
  92                                 <filename>/run/log/journal</filename>
  93                                 (which is created if needed), during
  94                                 early boot and if the disk is not
  95                                 writable. <literal>auto</literal> is
  96                                 similar to
  97                                 <literal>persistent</literal> but the
  98                                 directory
  99                                 <filename>/var/log/journal</filename>
 100                                 is not created if needed, so that its
 101                                 existence controls where log data
 102                                 goes. <literal>none</literal> turns
 103                                 off all storage, all log data received
 104                                 will be dropped. Forwarding to other
 105                                 targets, such as the console, the
 106                                 kernel log buffer or a syslog daemon
 107                                 will still work however.  Defaults to
 108                                 <literal>auto</literal>.</para></listitem>
 109                         </varlistentry>
 110
 111                         <varlistentry>
 112                                 <term><varname>Compress=</varname></term>
 113
 114                                 <listitem><para>Takes a boolean
 115                                 value. If enabled (the default), data
 116                                 objects that shall be stored in the
 117                                 journal and are larger than a certain
 118                                 threshold are compressed with the XZ
 119                                 compression algorithm before they are
 120                                 written to the file
 121                                 system.</para></listitem>
 122                         </varlistentry>
 123
 124                         <varlistentry>
 125                                 <term><varname>Seal=</varname></term>
 126
 127                                 <listitem><para>Takes a boolean
 128                                 value. If enabled (the default), and a
 129                                 sealing key is available (as created
 130                                 by
 131                                 <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
 132                                 <option>--setup-keys</option>
 133                                 command), Forward Secure Sealing (FSS)
 134                                 for all persistent journal files is
 135                                 enabled. FSS is based on <ulink
 136                                 url="https://eprint.iacr.org/2013/397">Seekable
 137                                 Sequential Key Generators</ulink> by
 138                                 G. A. Marson and B. Poettering
 139                                 (doi:10.1007/978-3-642-40203-6_7)
 140                                 and may be used to protect journal files
 141                                 from unnoticed alteration.</para></listitem>
 142                         </varlistentry>
 143
 144                         <varlistentry>
 145                                 <term><varname>SplitMode=</varname></term>
 146
 147                                 <listitem><para>Controls whether to
 148                                 split up journal files per user. One
 149                                 of <literal>login</literal>,
 150                                 <literal>uid</literal> and
 151                                 <literal>none</literal>. If
 152                                 <literal>login</literal>, each logged-in
 153                                 user will get his own journal
 154                                 files, but systemd user IDs will log
 155                                 into the system journal. If
 156                                 <literal>uid</literal>, any user ID
 157                                 will get his own journal files
 158                                 regardless of whether it belongs to a
 159                                 system service or refers to a real
 160                                 logged in user. If
 161                                 <literal>none</literal>, journal files
 162                                 are not split up by user and all
 163                                 messages are instead stored in the single
 164                                 system journal. Note that splitting
 165                                 up journal files by user is only
 166                                 available for journals stored
 167                                 persistently. If journals are stored
 168                                 on volatile storage (see above), only a
 169                                 single journal file for all user IDs
 170                                 is kept. Defaults to
 171                                 <literal>login</literal>.</para></listitem>
 172                         </varlistentry>
 173
 174                         <varlistentry>
 175                                 <term><varname>RateLimitInterval=</varname></term>
 176                                 <term><varname>RateLimitBurst=</varname></term>
 177
 178                                 <listitem><para>Configures the rate
 179                                 limiting that is applied to all
 180                                 messages generated on the system. If,
 181                                 in the time interval defined by
 182                                 <varname>RateLimitInterval=</varname>,
 183                                 more messages than specified in
 184                                 <varname>RateLimitBurst=</varname> are
 185                                 logged by a service, all further
 186                                 messages within the interval are
 187                                 dropped until the interval is over. A
 188                                 message about the number of dropped
 189                                 messages is generated. This rate
 190                                 limiting is applied per-service, so
 191                                 that two services which log do not
 192                                 interfere with each other's
 193                                 limits. Defaults to 200 messages in
 194                                 10s. The time specification for
 195                                 <varname>RateLimitInterval=</varname>
 196                                 may be specified in the following
 197                                 units: <literal>s</literal>,
 198                                 <literal>min</literal>,
 199                                 <literal>h</literal>,
 200                                 <literal>ms</literal>,
 201                                 <literal>us</literal>. To turn off any
 202                                 kind of rate limiting, set either
 203                                 value to 0.</para></listitem>
 204                         </varlistentry>
 205
 206                         <varlistentry>
 207                                 <term><varname>SystemMaxUse=</varname></term>
 208                                 <term><varname>SystemKeepFree=</varname></term>
 209                                 <term><varname>SystemMaxFileSize=</varname></term>
 210                                 <term><varname>RuntimeMaxUse=</varname></term>
 211                                 <term><varname>RuntimeKeepFree=</varname></term>
 212                                 <term><varname>RuntimeMaxFileSize=</varname></term>
 213
 214                                 <listitem><para>Enforce size limits on
 215                                 the journal files stored. The options
 216                                 prefixed with
 217                                 <literal>System</literal> apply to the
 218                                 journal files when stored on a
 219                                 persistent file system, more
 220                                 specifically
 221                                 <filename>/var/log/journal</filename>. The
 222                                 options prefixed with
 223                                 <literal>Runtime</literal> apply to
 224                                 the journal files when stored on a
 225                                 volatile in-memory file system, more
 226                                 specifically
 227                                 <filename>/run/log/journal</filename>. The
 228                                 former is used only when
 229                                 <filename>/var</filename> is mounted,
 230                                 writable, and the directory
 231                                 <filename>/var/log/journal</filename>
 232                                 exists. Otherwise, only the latter
 233                                 applies. Note that this means that
 234                                 during early boot and if the
 235                                 administrator disabled persistent
 236                                 logging, only the latter options apply,
 237                                 while the former apply if persistent
 238                                 logging is enabled and the system is
 239                                 fully booted
 240                                 up. <command>journalctl</command> and
 241                                 <command>systemd-journald</command>
 242                                 ignore all files with names not ending
 243                                 with <literal>.journal</literal> or
 244                                 <literal>.journal~</literal>, so only
 245                                 such files, located in the appropriate
 246                                 directories, are taken into account
 247                                 when calculating current disk usage.
 248                                 </para>
 249
 250                                 <para><varname>SystemMaxUse=</varname>
 251                                 and <varname>RuntimeMaxUse=</varname>
 252                                 control how much disk space the
 253                                 journal may use up at maximum.
 254                                 <varname>SystemKeepFree=</varname> and
 255                                 <varname>RuntimeKeepFree=</varname>
 256                                 control how much disk space
 257                                 systemd-journald shall leave free for
 258                                 other uses.
 259                                 <command>systemd-journald</command>
 260                                 will respect both limits and use the
 261                                 smaller of the two values.</para>
 262
 263                                 <para>The first pair defaults to 10%
 264                                 and the second to 15% of the size of
 265                                 the respective file system. If the
 266                                 file system is nearly full and either
 267                                 <varname>SystemKeepFree=</varname> or
 268                                 <varname>RuntimeKeepFree=</varname> is
 269                                 violated when systemd-journald is
 270                                 started, the value will be raised to
 271                                 percentage that is actually free. This
 272                                 means that if before there was enough
 273                                 free space and journal files were
 274                                 created, and subsequently something
 275                                 else causes the file system to fill
 276                                 up, journald will stop using more
 277                                 space, but it'll will not removing
 278                                 existing files to go reduce footprint
 279                                 either.</para>
 280
 281                                 <para><varname>SystemMaxFileSize=</varname>
 282                                 and
 283                                 <varname>RuntimeMaxFileSize=</varname>
 284                                 control how large individual journal
 285                                 files may grow at maximum. This
 286                                 influences the granularity in which
 287                                 disk space is made available through
 288                                 rotation, i.e. deletion of historic
 289                                 data. Defaults to one eighth of the
 290                                 values configured with
 291                                 <varname>SystemMaxUse=</varname> and
 292                                 <varname>RuntimeMaxUse=</varname>, so
 293                                 that usually seven rotated journal
 294                                 files are kept as history. Specify
 295                                 values in bytes or use K, M, G, T, P,
 296                                 E as units for the specified sizes
 297                                 (equal to 1024, 1024²,... bytes).
 298                                 Note that size limits are enforced
 299                                 synchronously when journal files are
 300                                 extended, and no explicit rotation
 301                                 step triggered by time is
 302                                 needed.</para></listitem>
 303                         </varlistentry>
 304
 305                         <varlistentry>
 306                                 <term><varname>MaxFileSec=</varname></term>
 307
 308                                 <listitem><para>The maximum time to
 309                                 store entries in a single journal
 310                                 file before rotating to the next
 311                                 one. Normally, time-based rotation
 312                                 should not be required as size-based
 313                                 rotation with options such as
 314                                 <varname>SystemMaxFileSize=</varname>
 315                                 should be sufficient to ensure that
 316                                 journal files do not grow without
 317                                 bounds. However, to ensure that not
 318                                 too much data is lost at once when old
 319                                 journal files are deleted, it might
 320                                 make sense to change this value from
 321                                 the default of one month. Set to 0 to
 322                                 turn off this feature. This setting
 323                                 takes time values which may be
 324                                 suffixed with the units
 325                                 <literal>year</literal>,
 326                                 <literal>month</literal>,
 327                                 <literal>week</literal>, <literal>day</literal>,
 328                                 <literal>h</literal> or <literal>m</literal>
 329                                 to override the default time unit of
 330                                 seconds.</para></listitem>
 331                         </varlistentry>
 332
 333                         <varlistentry>
 334                                 <term><varname>MaxRetentionSec=</varname></term>
 335
 336                                 <listitem><para>The maximum time to
 337                                 store journal entries. This
 338                                 controls whether journal files
 339                                 containing entries older then the
 340                                 specified time span are
 341                                 deleted. Normally, time-based deletion
 342                                 of old journal files should not be
 343                                 required as size-based deletion with
 344                                 options such as
 345                                 <varname>SystemMaxUse=</varname>
 346                                 should be sufficient to ensure that
 347                                 journal files do not grow without
 348                                 bounds. However, to enforce data
 349                                 retention policies, it might make sense
 350                                 to change this value from the
 351                                 default of 0 (which turns off this
 352                                 feature). This setting also takes
 353                                 time values which may be suffixed with
 354                                 the units <literal>year</literal>,
 355                                 <literal>month</literal>,
 356                                 <literal>week</literal>, <literal>day</literal>,
 357                                 <literal>h</literal> or <literal> m</literal>
 358                                 to override the default time unit of
 359                                 seconds.</para></listitem>
 360                         </varlistentry>
 361
 362
 363                         <varlistentry>
 364                                 <term><varname>SyncIntervalSec=</varname></term>
 365
 366                                 <listitem><para>The timeout before
 367                                 synchronizing journal files to
 368                                 disk. After syncing, journal files are
 369                                 placed in the OFFLINE state. Note that
 370                                 syncing is unconditionally done
 371                                 immediately after a log message of
 372                                 priority CRIT, ALERT or EMERG has been
 373                                 logged. This setting hence applies
 374                                 only to messages of the levels ERR,
 375                                 WARNING, NOTICE, INFO, DEBUG. The
 376                                 default timeout is 5 minutes.
 377                                 </para></listitem>
 378                         </varlistentry>
 379
 380                         <varlistentry>
 381                                 <term><varname>ForwardToSyslog=</varname></term>
 382                                 <term><varname>ForwardToKMsg=</varname></term>
 383                                 <term><varname>ForwardToConsole=</varname></term>
 384
 385                                 <listitem><para>Control whether log
 386                                 messages received by the journal
 387                                 daemon shall be forwarded to a
 388                                 traditional syslog daemon, to the
 389                                 kernel log buffer (kmsg), or to the
 390                                 system console. These options take
 391                                 boolean arguments. If forwarding to
 392                                 syslog is enabled but no syslog daemon
 393                                 is running, the respective option has
 394                                 no effect. By default, only forwarding
 395                                 to syslog is enabled. These settings
 396                                 may be overridden at boot time with
 397                                 the kernel command line options
 398                                 <literal>systemd.journald.forward_to_syslog=</literal>,
 399                                 <literal>systemd.journald.forward_to_kmsg=</literal>
 400                                 and
 401                                 <literal>systemd.journald.forward_to_console=</literal>.
 402                                 When forwarding to the console, the
 403                                 TTY to log to log to can be changed
 404                                 with <varname>TTYPath=</varname>,
 405                                 described below.</para></listitem>
 406                         </varlistentry>
 407
 408                         <varlistentry>
 409                                 <term><varname>MaxLevelStore=</varname></term>
 410                                 <term><varname>MaxLevelSyslog=</varname></term>
 411                                 <term><varname>MaxLevelKMsg=</varname></term>
 412                                 <term><varname>MaxLevelConsole=</varname></term>
 413
 414                                 <listitem><para>Controls the maximum
 415                                 log level of messages that are stored
 416                                 on disk, forwarded to syslog, kmsg or
 417                                 the console (if that is enabled, see
 418                                 above). As argument, takes one of
 419                                 <literal>emerg</literal>,
 420                                 <literal>alert</literal>,
 421                                 <literal>crit</literal>,
 422                                 <literal>err</literal>,
 423                                 <literal>warning</literal>,
 424                                 <literal>notice</literal>,
 425                                 <literal>info</literal>,
 426                                 <literal>debug</literal> or integer
 427                                 values in the range of 0..7 (corresponding
 428                                 to the same levels). Messages equal or below
 429                                 the log level specified are
 430                                 stored/forwarded, messages above are
 431                                 dropped. Defaults to
 432                                 <literal>debug</literal> for
 433                                 <varname>MaxLevelStore=</varname> and
 434                                 <varname>MaxLevelSyslog=</varname>, to
 435                                 ensure that the all messages are
 436                                 written to disk and forwarded to
 437                                 syslog. Defaults to
 438                                 <literal>notice</literal> for
 439                                 <varname>MaxLevelKMsg=</varname> and
 440                                 <literal>info</literal> for
 441                                 <varname>MaxLevelConsole=</varname>.</para></listitem>
 442                         </varlistentry>
 443
 444                         <varlistentry>
 445                                 <term><varname>TTYPath=</varname></term>
 446
 447                                 <listitem><para>Change the console TTY
 448                                 to use if
 449                                 <varname>ForwardToConsole=yes</varname>
 450                                 is used. Defaults to
 451                                 <filename>/dev/console</filename>.</para></listitem>
 452                         </varlistentry>
 453
 454                 </variablelist>
 455
 456         </refsect1>
 457
 458         <refsect1>
 459                   <title>See Also</title>
 460                   <para>
 461                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 462                           <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 463                           <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 464                           <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 465                           <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 466                   </para>
 467         </refsect1>
 468
 469 </refentry>