man/journald.conf.xml

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  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>uid</literal>,
 150                                 <literal>login</literal> and
 151                                 <literal>none</literal>.  If
 152                                 <literal>uid</literal>, all users will
 153                                 get each their own journal files
 154                                 regardless of whether they possess a
 155                                 login session or not, however system
 156                                 users will log into the system
 157                                 journal. If <literal>login</literal>,
 158                                 actually logged-in users will get each
 159                                 their own journal files, but users
 160                                 without login session and system users
 161                                 will log into the system journal. If
 162                                 <literal>none</literal>, journal files
 163                                 are not split up by user and all
 164                                 messages are instead stored in the
 165                                 single system journal. Note that
 166                                 splitting up journal files by user is
 167                                 only available for journals stored
 168                                 persistently. If journals are stored
 169                                 on volatile storage (see above), only
 170                                 a single journal file for all user IDs
 171                                 is kept. Defaults to
 172                                 <literal>uid</literal>.</para></listitem>
 173                         </varlistentry>
 174
 175                         <varlistentry>
 176                                 <term><varname>RateLimitInterval=</varname></term>
 177                                 <term><varname>RateLimitBurst=</varname></term>
 178
 179                                 <listitem><para>Configures the rate
 180                                 limiting that is applied to all
 181                                 messages generated on the system. If,
 182                                 in the time interval defined by
 183                                 <varname>RateLimitInterval=</varname>,
 184                                 more messages than specified in
 185                                 <varname>RateLimitBurst=</varname> are
 186                                 logged by a service, all further
 187                                 messages within the interval are
 188                                 dropped until the interval is over. A
 189                                 message about the number of dropped
 190                                 messages is generated. This rate
 191                                 limiting is applied per-service, so
 192                                 that two services which log do not
 193                                 interfere with each other's
 194                                 limits. Defaults to 1000 messages in
 195                                 30s. The time specification for
 196                                 <varname>RateLimitInterval=</varname>
 197                                 may be specified in the following
 198                                 units: <literal>s</literal>,
 199                                 <literal>min</literal>,
 200                                 <literal>h</literal>,
 201                                 <literal>ms</literal>,
 202                                 <literal>us</literal>. To turn off any
 203                                 kind of rate limiting, set either
 204                                 value to 0.</para></listitem>
 205                         </varlistentry>
 206
 207                         <varlistentry>
 208                                 <term><varname>SystemMaxUse=</varname></term>
 209                                 <term><varname>SystemKeepFree=</varname></term>
 210                                 <term><varname>SystemMaxFileSize=</varname></term>
 211                                 <term><varname>RuntimeMaxUse=</varname></term>
 212                                 <term><varname>RuntimeKeepFree=</varname></term>
 213                                 <term><varname>RuntimeMaxFileSize=</varname></term>
 214
 215                                 <listitem><para>Enforce size limits on
 216                                 the journal files stored. The options
 217                                 prefixed with
 218                                 <literal>System</literal> apply to the
 219                                 journal files when stored on a
 220                                 persistent file system, more
 221                                 specifically
 222                                 <filename>/var/log/journal</filename>. The
 223                                 options prefixed with
 224                                 <literal>Runtime</literal> apply to
 225                                 the journal files when stored on a
 226                                 volatile in-memory file system, more
 227                                 specifically
 228                                 <filename>/run/log/journal</filename>. The
 229                                 former is used only when
 230                                 <filename>/var</filename> is mounted,
 231                                 writable, and the directory
 232                                 <filename>/var/log/journal</filename>
 233                                 exists. Otherwise, only the latter
 234                                 applies. Note that this means that
 235                                 during early boot and if the
 236                                 administrator disabled persistent
 237                                 logging, only the latter options apply,
 238                                 while the former apply if persistent
 239                                 logging is enabled and the system is
 240                                 fully booted
 241                                 up. <command>journalctl</command> and
 242                                 <command>systemd-journald</command>
 243                                 ignore all files with names not ending
 244                                 with <literal>.journal</literal> or
 245                                 <literal>.journal~</literal>, so only
 246                                 such files, located in the appropriate
 247                                 directories, are taken into account
 248                                 when calculating current disk usage.
 249                                 </para>
 250
 251                                 <para><varname>SystemMaxUse=</varname>
 252                                 and <varname>RuntimeMaxUse=</varname>
 253                                 control how much disk space the
 254                                 journal may use up at maximum.
 255                                 <varname>SystemKeepFree=</varname> and
 256                                 <varname>RuntimeKeepFree=</varname>
 257                                 control how much disk space
 258                                 systemd-journald shall leave free for
 259                                 other uses.
 260                                 <command>systemd-journald</command>
 261                                 will respect both limits and use the
 262                                 smaller of the two values.</para>
 263
 264                                 <para>The first pair defaults to 10%
 265                                 and the second to 15% of the size of
 266                                 the respective file system. If the
 267                                 file system is nearly full and either
 268                                 <varname>SystemKeepFree=</varname> or
 269                                 <varname>RuntimeKeepFree=</varname> is
 270                                 violated when systemd-journald is
 271                                 started, the value will be raised to
 272                                 percentage that is actually free. This
 273                                 means that if there was enough
 274                                 free space before and journal files were
 275                                 created, and subsequently something
 276                                 else causes the file system to fill
 277                                 up, journald will stop using more
 278                                 space, but it will not be removing
 279                                 existing files to go reduce footprint
 280                                 either.</para>
 281
 282                                 <para><varname>SystemMaxFileSize=</varname>
 283                                 and
 284                                 <varname>RuntimeMaxFileSize=</varname>
 285                                 control how large individual journal
 286                                 files may grow at maximum. This
 287                                 influences the granularity in which
 288                                 disk space is made available through
 289                                 rotation, i.e. deletion of historic
 290                                 data. Defaults to one eighth of the
 291                                 values configured with
 292                                 <varname>SystemMaxUse=</varname> and
 293                                 <varname>RuntimeMaxUse=</varname>, so
 294                                 that usually seven rotated journal
 295                                 files are kept as history. Specify
 296                                 values in bytes or use K, M, G, T, P,
 297                                 E as units for the specified sizes
 298                                 (equal to 1024, 1024²,... bytes).
 299                                 Note that size limits are enforced
 300                                 synchronously when journal files are
 301                                 extended, and no explicit rotation
 302                                 step triggered by time is
 303                                 needed.</para></listitem>
 304                         </varlistentry>
 305
 306                         <varlistentry>
 307                                 <term><varname>MaxFileSec=</varname></term>
 308
 309                                 <listitem><para>The maximum time to
 310                                 store entries in a single journal
 311                                 file before rotating to the next
 312                                 one. Normally, time-based rotation
 313                                 should not be required as size-based
 314                                 rotation with options such as
 315                                 <varname>SystemMaxFileSize=</varname>
 316                                 should be sufficient to ensure that
 317                                 journal files do not grow without
 318                                 bounds. However, to ensure that not
 319                                 too much data is lost at once when old
 320                                 journal files are deleted, it might
 321                                 make sense to change this value from
 322                                 the default of one month. Set to 0 to
 323                                 turn off this feature. This setting
 324                                 takes time values which may be
 325                                 suffixed with the units
 326                                 <literal>year</literal>,
 327                                 <literal>month</literal>,
 328                                 <literal>week</literal>, <literal>day</literal>,
 329                                 <literal>h</literal> or <literal>m</literal>
 330                                 to override the default time unit of
 331                                 seconds.</para></listitem>
 332                         </varlistentry>
 333
 334                         <varlistentry>
 335                                 <term><varname>MaxRetentionSec=</varname></term>
 336
 337                                 <listitem><para>The maximum time to
 338                                 store journal entries. This
 339                                 controls whether journal files
 340                                 containing entries older then the
 341                                 specified time span are
 342                                 deleted. Normally, time-based deletion
 343                                 of old journal files should not be
 344                                 required as size-based deletion with
 345                                 options such as
 346                                 <varname>SystemMaxUse=</varname>
 347                                 should be sufficient to ensure that
 348                                 journal files do not grow without
 349                                 bounds. However, to enforce data
 350                                 retention policies, it might make sense
 351                                 to change this value from the
 352                                 default of 0 (which turns off this
 353                                 feature). This setting also takes
 354                                 time values which may be suffixed with
 355                                 the units <literal>year</literal>,
 356                                 <literal>month</literal>,
 357                                 <literal>week</literal>, <literal>day</literal>,
 358                                 <literal>h</literal> or <literal> m</literal>
 359                                 to override the default time unit of
 360                                 seconds.</para></listitem>
 361                         </varlistentry>
 362
 363
 364                         <varlistentry>
 365                                 <term><varname>SyncIntervalSec=</varname></term>
 366
 367                                 <listitem><para>The timeout before
 368                                 synchronizing journal files to
 369                                 disk. After syncing, journal files are
 370                                 placed in the OFFLINE state. Note that
 371                                 syncing is unconditionally done
 372                                 immediately after a log message of
 373                                 priority CRIT, ALERT or EMERG has been
 374                                 logged. This setting hence applies
 375                                 only to messages of the levels ERR,
 376                                 WARNING, NOTICE, INFO, DEBUG. The
 377                                 default timeout is 5 minutes.
 378                                 </para></listitem>
 379                         </varlistentry>
 380
 381                         <varlistentry>
 382                                 <term><varname>ForwardToSyslog=</varname></term>
 383                                 <term><varname>ForwardToKMsg=</varname></term>
 384                                 <term><varname>ForwardToConsole=</varname></term>
 385                                 <term><varname>ForwardToWall=</varname></term>
 386
 387                                 <listitem><para>Control whether log
 388                                 messages received by the journal
 389                                 daemon shall be forwarded to a
 390                                 traditional syslog daemon, to the
 391                                 kernel log buffer (kmsg), to the
 392                                 system console, or sent as wall
 393                                 messages to all logged-in users. These
 394                                 options take boolean arguments. If
 395                                 forwarding to syslog is enabled but no
 396                                 syslog daemon is running, the
 397                                 respective option has no effect. By
 398                                 default, only forwarding to syslog and
 399                                 wall is enabled. These settings may be
 400                                 overridden at boot time with the
 401                                 kernel command line options
 402                                 <literal>systemd.journald.forward_to_syslog=</literal>,
 403                                 <literal>systemd.journald.forward_to_kmsg=</literal>,
 404                                 <literal>systemd.journald.forward_to_console=</literal>
 405                                 and
 406                                 <literal>systemd.journald.forward_to_wall=</literal>.
 407                                 When forwarding to the console, the
 408                                 TTY to log to can be changed
 409                                 with <varname>TTYPath=</varname>,
 410                                 described below.</para></listitem>
 411                         </varlistentry>
 412
 413                         <varlistentry>
 414                                 <term><varname>MaxLevelStore=</varname></term>
 415                                 <term><varname>MaxLevelSyslog=</varname></term>
 416                                 <term><varname>MaxLevelKMsg=</varname></term>
 417                                 <term><varname>MaxLevelConsole=</varname></term>
 418                                 <term><varname>MaxLevelWall=</varname></term>
 419
 420                                 <listitem><para>Controls the maximum
 421                                 log level of messages that are stored
 422                                 on disk, forwarded to syslog, kmsg,
 423                                 the console or wall (if that is
 424                                 enabled, see above). As argument,
 425                                 takes one of
 426                                 <literal>emerg</literal>,
 427                                 <literal>alert</literal>,
 428                                 <literal>crit</literal>,
 429                                 <literal>err</literal>,
 430                                 <literal>warning</literal>,
 431                                 <literal>notice</literal>,
 432                                 <literal>info</literal>,
 433                                 <literal>debug</literal> or integer
 434                                 values in the range of 0..7 (corresponding
 435                                 to the same levels). Messages equal or below
 436                                 the log level specified are
 437                                 stored/forwarded, messages above are
 438                                 dropped. Defaults to
 439                                 <literal>debug</literal> for
 440                                 <varname>MaxLevelStore=</varname> and
 441                                 <varname>MaxLevelSyslog=</varname>, to
 442                                 ensure that the all messages are
 443                                 written to disk and forwarded to
 444                                 syslog. Defaults to
 445                                 <literal>notice</literal> for
 446                                 <varname>MaxLevelKMsg=</varname>,
 447                                 <literal>info</literal> for
 448                                 <varname>MaxLevelConsole=</varname> and
 449                                 <literal>emerg</literal> for
 450                                 <varname>MaxLevelWall=</varname>.</para></listitem>
 451                         </varlistentry>
 452
 453                         <varlistentry>
 454                                 <term><varname>TTYPath=</varname></term>
 455
 456                                 <listitem><para>Change the console TTY
 457                                 to use if
 458                                 <varname>ForwardToConsole=yes</varname>
 459                                 is used. Defaults to
 460                                 <filename>/dev/console</filename>.</para></listitem>
 461                         </varlistentry>
 462
 463                 </variablelist>
 464
 465         </refsect1>
 466
 467         <refsect1>
 468                   <title>See Also</title>
 469                   <para>
 470                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 471                           <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 472                           <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 473                           <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 474                           <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 475                   </para>
 476         </refsect1>
 477
 478 </refentry>