man/journalctl.xml

   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">
   4
   5 <!--
   6   This file is part of systemd.
   7
   8   Copyright 2012 Lennart Poettering
   9
  10   systemd is free software; you can redistribute it and/or modify it
  11   under the terms of the GNU Lesser General Public License as published by
  12   the Free Software Foundation; either version 2.1 of the License, or
  13   (at your option) any later version.
  14
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  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   Lesser General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  22 -->
  23
  24 <refentry id="journalctl">
  25
  26         <refentryinfo>
  27                 <title>journalctl</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>journalctl</refentrytitle>
  42                 <manvolnum>1</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>journalctl</refname>
  47                 <refpurpose>Query the systemd journal</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <cmdsynopsis>
  52                         <command>journalctl</command>
  53                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  54                         <arg choice="opt" rep="repeat">MATCHES</arg>
  55                 </cmdsynopsis>
  56         </refsynopsisdiv>
  57
  58         <refsect1>
  59                 <title>Description</title>
  60
  61                 <para><command>journalctl</command> may be used to
  62                 query the contents of the
  63                 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  64                 journal as written by
  65                 <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
  66
  67                 <para>If called without parameters, it will show the full
  68                 contents of the journal, starting with the oldest
  69                 entry collected.</para>
  70
  71                 <para>If one or more match arguments are passed, the
  72                 output is filtered accordingly. A match is in the
  73                 format <literal>FIELD=VALUE</literal>,
  74                 e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>,
  75                 referring to the components of a structured journal
  76                 entry. See
  77                 <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>
  78                 for a list of well-known fields. If multiple matches
  79                 are specified matching different fields, the log
  80                 entries are filtered by both, i.e. the resulting output
  81                 will show only entries matching all the specified
  82                 matches of this kind. If two matches apply to the same
  83                 field, then they are automatically matched as
  84                 alternatives, i.e. the resulting output will show
  85                 entries matching any of the specified matches for the
  86                 same field. Finally, if the character
  87                 <literal>+</literal> appears as separate word on the
  88                 command line, all matches before and after are combined
  89                 in a disjunction (i.e. logical OR).</para>
  90
  91                 <para>As shortcuts for a few types of field/value
  92                 matches, file paths may be specified. If a file path
  93                 refers to an executable file, this is equivalent to an
  94                 <literal>_EXE=</literal> match for the canonicalized
  95                 binary path. Similarly, if a path refers to a device
  96                 node, this is equivalent to a
  97                 <literal>_KERNEL_DEVICE=</literal> match for the
  98                 device.</para>
  99
 100                 <para>Output is interleaved from all accessible
 101                 journal files, whether they are rotated or currently
 102                 being written, and regardless of whether they belong to the
 103                 system itself or are accessible user journals.</para>
 104
 105                 <para>All users are granted access to their private
 106                 per-user journals. However, by default, only root and
 107                 users who are members of the <literal>adm</literal>
 108                 group get access to the system journal and the
 109                 journals of other users.</para>
 110
 111                 <para>The output is paged through
 112                 <command>less</command> by default, and long lines are
 113                 "truncated" to screen width. The hidden part can be
 114                 viewed by using the left-arrow and right-arrow
 115                 keys. Paging can be disabled, see
 116                 <option>--no-pager</option> and section Environment
 117                 below.</para>
 118
 119                 <para>When outputing to a tty, lines are colored
 120                 according to priority: lines of level ERROR and higher
 121                 are colored red, lines of level NOTICE and higher are
 122                 highlighted, and other lines are displayed normally.
 123                 </para>
 124         </refsect1>
 125
 126         <refsect1>
 127                 <title>Options</title>
 128
 129                 <para>The following options are understood:</para>
 130
 131                 <variablelist>
 132                         <varlistentry>
 133                                 <term><option>-h</option></term>
 134                                 <term><option>--help</option></term>
 135
 136                                 <listitem><para>Prints a short help
 137                                 text and exits.</para></listitem>
 138                         </varlistentry>
 139
 140                         <varlistentry>
 141                                 <term><option>--version</option></term>
 142
 143                                 <listitem><para>Prints a short version
 144                                 string and exits.</para></listitem>
 145                         </varlistentry>
 146
 147                         <varlistentry>
 148                                 <term><option>--no-pager</option></term>
 149
 150                                 <listitem><para>Do not pipe output into a
 151                                 pager.</para></listitem>
 152                         </varlistentry>
 153
 154                         <varlistentry>
 155                                 <term><option>-l</option></term>
 156                                 <term><option>--full</option></term>
 157
 158                                 <listitem><para>Show all (printable) fields in
 159                                 full.</para></listitem>
 160                         </varlistentry>
 161
 162                         <varlistentry>
 163                                 <term><option>-a</option></term>
 164                                 <term><option>--all</option></term>
 165
 166                                 <listitem><para>Show all fields in
 167                                 full, even if they include unprintable
 168                                 characters or are very
 169                                 long.</para></listitem>
 170                         </varlistentry>
 171
 172                         <varlistentry>
 173                                 <term><option>-f</option></term>
 174                                 <term><option>--follow</option></term>
 175
 176                                 <listitem><para>Show only the most recent
 177                                 journal entries, and continuously print
 178                                 new entries as they are appended to
 179                                 the journal.</para></listitem>
 180                         </varlistentry>
 181
 182                         <varlistentry>
 183                                 <term><option>-e</option></term>
 184                                 <term><option>--pager-end</option></term>
 185
 186                                 <listitem><para>Immediately jump to
 187                                 the end of the journal inside the
 188                                 implied pager tool. This implies
 189                                 <option>-n1000</option> to guarantee
 190                                 that the pager will not buffer logs of
 191                                 unbounded size. This may be overridden
 192                                 with an explicit <option>-n</option>
 193                                 with some other numeric value on the
 194                                 command line. Note that this option is
 195                                 only supported for the
 196                                 <citerefentry><refentrytitle>less</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 197                                 pager.</para></listitem>
 198                         </varlistentry>
 199
 200                         <varlistentry>
 201                                 <term><option>-n</option></term>
 202                                 <term><option>--lines=</option></term>
 203
 204                                 <listitem><para>Show the most recent
 205                                 journal events and limit the number of
 206                                 events shown. If
 207                                 <option>--follow</option> is used,
 208                                 this option is implied. The argument,
 209                                 a positive integer, is optional, and
 210                                 defaults to 10. </para></listitem>
 211                         </varlistentry>
 212
 213                         <varlistentry>
 214                                 <term><option>--no-tail</option></term>
 215
 216                                 <listitem><para>Show all stored output
 217                                 lines, even in follow mode. Undoes the
 218                                 effect of
 219                                 <option>--lines=</option>.</para></listitem>
 220                         </varlistentry>
 221
 222                         <varlistentry>
 223                                 <term><option>-r</option></term>
 224                                 <term><option>--reverse</option></term>
 225
 226                                 <listitem><para>Reverse output, so the newest
 227                                 entries are displayed first.</para></listitem>
 228                         </varlistentry>
 229
 230                         <varlistentry>
 231                                 <term><option>-o</option></term>
 232                                 <term><option>--output=</option></term>
 233
 234                                 <listitem><para>Controls the
 235                                 formatting of the journal entries that
 236                                 are shown. Takes one of the following options:
 237                                 </para>
 238                                 <variablelist>
 239                                         <varlistentry>
 240                                                 <term>
 241                                                         <option>short</option>
 242                                                 </term>
 243                                                 <listitem>
 244                                                         <para>is the default
 245                                                         and generates an output
 246                                                         that is mostly identical
 247                                                         to the formatting of
 248                                                         classic syslog files,
 249                                                         showing one line per
 250                                                         journal entry.</para>
 251                                                 </listitem>
 252                                         </varlistentry>
 253
 254                                         <varlistentry>
 255                                                 <term>
 256                                                         <option>short-monotonic</option>
 257                                                 </term>
 258                                                 <listitem>
 259                                                         <para>is very similar
 260                                                         but shows monotonic
 261                                                         timestamps instead of
 262                                                         wallclock timestamps.
 263                                                         </para>
 264                                                 </listitem>
 265                                         </varlistentry>
 266
 267                                         <varlistentry>
 268                                                 <term>
 269                                                         <option>short-iso</option>
 270                                                 </term>
 271                                                 <listitem>
 272                                                         <para>is very similar
 273                                                         but shows ISO 8601
 274                                                         wallclock timestamps.
 275                                                         </para>
 276                                                 </listitem>
 277                                         </varlistentry>
 278
 279                                         <varlistentry>
 280                                                 <term>
 281                                                         <option>verbose</option>
 282                                                 </term>
 283                                                 <listitem>
 284                                                         <para>shows the
 285                                                         full-structured entry
 286                                                         items with all fields.
 287                                                         </para>
 288                                                 </listitem>
 289                                         </varlistentry>
 290
 291                                         <varlistentry>
 292                                                 <term>
 293                                                         <option>export</option>
 294                                                 </term>
 295                                                 <listitem>
 296                                                         <para>serializes the
 297                                                         journal into a binary
 298                                                         (but mostly text-based)
 299                                                         stream suitable for
 300                                                         backups and network
 301                                                         transfer (see <ulink
 302                                                         url="http://www.freedesktop.org/wiki/Software/systemd/export">Journal
 303                                                         Export Format</ulink>
 304                                                         for more
 305                                                         information).</para>
 306                                                 </listitem>
 307                                         </varlistentry>
 308
 309                                         <varlistentry>
 310                                                 <term>
 311                                                         <option>json</option>
 312                                                 </term>
 313                                                 <listitem>
 314                                                         <para>formats entries
 315                                                         as JSON data structures,
 316                                                         one per line (see <ulink
 317                                                         url="http://www.freedesktop.org/wiki/Software/systemd/json">Journal
 318                                                         JSON Format</ulink> for
 319                                                         more information).</para>
 320                                                 </listitem>
 321                                         </varlistentry>
 322
 323                                         <varlistentry>
 324                                                 <term>
 325                                                         <option>json-pretty</option>
 326                                                 </term>
 327                                                 <listitem>
 328                                                         <para>formats entries as
 329                                                         JSON data structures,
 330                                                         but formats them in
 331                                                         multiple lines in order
 332                                                         to make them more
 333                                                         readable for humans.</para>
 334                                                 </listitem>
 335                                         </varlistentry>
 336
 337                                         <varlistentry>
 338                                                 <term>
 339                                                         <option>json-sse</option>
 340                                                 </term>
 341                                                 <listitem>
 342                                                         <para>formats entries as
 343                                                         JSON data structures,
 344                                                         but wraps them in a
 345                                                         format suitable for <ulink
 346                                                         url="https://developer.mozilla.org/en-US/docs/Server-sent_events/Using_server-sent_events">Server-Sent
 347                                                         Events</ulink>.</para>
 348                                                 </listitem>
 349                                         </varlistentry>
 350
 351                                         <varlistentry>
 352                                                 <term>
 353                                                         <option>cat</option>
 354                                                 </term>
 355                                                 <listitem>
 356                                                         <para>generates a very
 357                                                         terse output only
 358                                                         showing the actual
 359                                                         message of each journal
 360                                                         entry with no meta data,
 361                                                         not even a timestamp.
 362                                                         </para>
 363                                                 </listitem>
 364                                         </varlistentry>
 365                                 </variablelist>
 366                                 </listitem>
 367                         </varlistentry>
 368
 369                         <varlistentry>
 370                                 <term><option>-x</option></term>
 371                                 <term><option>--catalog</option></term>
 372
 373                                 <listitem><para>Augment log lines with
 374                                 explanation texts from the message
 375                                 catalog. This will add explanatory
 376                                 help texts to log messages in the
 377                                 output where this is available. These
 378                                 short help texts will explain the
 379                                 context of an error or log event,
 380                                 possible solutions, as well as
 381                                 pointers to support forums, developer
 382                                 documentation and any other relevant
 383                                 manuals. Note that help texts are not
 384                                 available for all messages, but only
 385                                 for selected ones. For more
 386                                 information on the message catalog,
 387                                 please refer to the <ulink
 388                                 url="http://www.freedesktop.org/wiki/Software/systemd/catalog">Message
 389                                 Catalog Developer
 390                                 Documentation</ulink>.</para></listitem>
 391                         </varlistentry>
 392
 393                         <varlistentry>
 394                                 <term><option>-q</option></term>
 395                                 <term><option>--quiet</option></term>
 396
 397                                 <listitem><para>Suppresses any warning
 398                                 message regarding inaccessible system
 399                                 journals when run as normal
 400                                 user.</para></listitem>
 401                         </varlistentry>
 402
 403                         <varlistentry>
 404                                 <term><option>-m</option></term>
 405                                 <term><option>--merge</option></term>
 406
 407                                 <listitem><para>Show entries
 408                                 interleaved from all available
 409                                 journals, including remote
 410                                 ones.</para></listitem>
 411                         </varlistentry>
 412
 413                         <varlistentry>
 414                                 <term><option>-b <optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional></option></term>
 415                                 <term><option>--boot=<optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional></option></term>
 416
 417                                 <listitem><para>Show messages from a specific
 418                                 boot. This will add a match for
 419                                 <literal>_BOOT_ID=</literal>.</para>
 420
 421                                 <para>The argument may be empty, in which case
 422                                 logs for the current boot will be shown.</para>
 423
 424                                 <para>If the boot ID is omitted, a positive
 425                                 <replaceable>offset</replaceable> will look up
 426                                 the boots starting from the beginning of the
 427                                 journal, and a equal-or-less-than zero
 428                                 <replaceable>offset</replaceable> will look up
 429                                 boots starting from the end of the
 430                                 journal. Thus, <constant>1</constant> means the
 431                                 first boot found in the journal in the
 432                                 chronological order, <constant>2</constant> the
 433                                 second and so on; while <constant>-0</constant>
 434                                 is the last boot, <constant>-1</constant> the
 435                                 boot before that, and so on. An empty
 436                                 <replaceable>offset</replaceable> is equivalent
 437                                 to specifying <constant>-0</constant>, except
 438                                 when the current boot is not the last boot
 439                                 (e.g. because <option>--directory</option> was
 440                                 specified to look at logs from a different
 441                                 machine).</para>
 442
 443                                 <para>If the 32 character
 444                                 <replaceable>ID</replaceable> is specified, it
 445                                 may optionally be followed by
 446                                 <replaceable>offset</replaceable> which
 447                                 identifies the boot relative to the one given by
 448                                 boot <replaceable>ID</replaceable>. Negative
 449                                 values mean earlier boots and a positive values
 450                                 mean later boots. If
 451                                 <replaceable>offset</replaceable> is not
 452                                 specified, a value of zero is assumed and the
 453                                 logs for the boot given by
 454                                 <replaceable>ID</replaceable> are shown.
 455                                 </para>
 456
 457                                 </listitem>
 458                         </varlistentry>
 459
 460                         <varlistentry>
 461                                 <term><option>-k</option></term>
 462                                 <term><option>--dmesg</option></term>
 463
 464                                 <listitem><para>Show only kernel messages. This
 465                                 implies <option>-b</option> and adds the match
 466                                 <literal>_TRANSPORT=kernel</literal>.
 467                                 </para></listitem>
 468                         </varlistentry>
 469
 470                         <varlistentry>
 471                                 <term><option>-u</option></term>
 472                                 <term><option>--unit=</option></term>
 473
 474                                 <listitem><para>Show messages for the
 475                                 specified systemd unit. This will add
 476                                 a match for messages from the unit
 477                                 (<literal>_SYSTEMD_UNIT=</literal>)
 478                                 and additional matches for messages
 479                                 from systemd and messages about
 480                                 coredumps for the specified unit.</para>
 481                                 <para>This parameter can be specified multiple times.
 482                                 </para></listitem>
 483                         </varlistentry>
 484
 485                         <varlistentry>
 486                                 <term><option>--user-unit=</option></term>
 487
 488                                 <listitem><para>Show messages for the
 489                                 specified user session unit. This will
 490                                 add a match for messages from the unit
 491                                 (<literal>_SYSTEMD_USER_UNIT=</literal>
 492                                 and <literal>_UID=</literal>) and
 493                                 additional matches for messages from
 494                                 session systemd and messages about
 495                                 coredumps for the specified unit.</para>
 496                                 <para>This parameter can be specified multiple times.
 497                                 </para></listitem>
 498                         </varlistentry>
 499
 500                         <varlistentry>
 501                                 <term><option>-p</option></term>
 502                                 <term><option>--priority=</option></term>
 503
 504                                 <listitem><para>Filter output by
 505                                 message priorities or priority
 506                                 ranges. Takes either a single numeric
 507                                 or textual log level (i.e. between
 508                                 0/<literal>emerg</literal> and
 509                                 7/<literal>debug</literal>), or a
 510                                 range of numeric/text log levels in
 511                                 the form FROM..TO. The log levels are
 512                                 the usual syslog log levels as
 513                                 documented in
 514                                 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 515                                 i.e. <literal>emerg</literal> (0),
 516                                 <literal>alert</literal> (1),
 517                                 <literal>crit</literal> (2),
 518                                 <literal>err</literal> (3),
 519                                 <literal>warning</literal> (4),
 520                                 <literal>notice</literal> (5),
 521                                 <literal>info</literal> (6),
 522                                 <literal>debug</literal> (7). If a
 523                                 single log level is specified, all
 524                                 messages with this log level or a
 525                                 lower (hence more important) log level
 526                                 are shown. If a range is specified, all
 527                                 messages within the range are shown,
 528                                 including both the start and the end
 529                                 value of the range. This will add
 530                                 <literal>PRIORITY=</literal> matches
 531                                 for the specified
 532                                 priorities.</para></listitem>
 533                         </varlistentry>
 534
 535                         <varlistentry>
 536                                 <term><option>-c</option></term>
 537                                 <term><option>--cursor=</option></term>
 538
 539                                 <listitem><para>Start showing entries
 540                                 from the location in the journal
 541                                 specified by the passed
 542                                 cursor.</para></listitem>
 543                         </varlistentry>
 544
 545                         <varlistentry>
 546                                 <term><option>--after-cursor=</option></term>
 547
 548                                 <listitem><para>Start showing entries from the
 549                                 location in the journal
 550                                 <emphasis>after</emphasis> the location
 551                                 specified by the this cursor.
 552                                 </para></listitem>
 553                         </varlistentry>
 554
 555                         <varlistentry>
 556                                 <term><option>--since=</option></term>
 557                                 <term><option>--until=</option></term>
 558
 559                                 <listitem><para>Start showing entries
 560                                 on or newer than the specified date,
 561                                 or on or older than the specified
 562                                 date, respectively. Date specifications
 563                                 should be of the format
 564                                 <literal>2012-10-30 18:17:16</literal>.
 565                                 If the time part is omitted,
 566                                 <literal>00:00:00</literal> is assumed.
 567                                 If only the seconds component is omitted,
 568                                 <literal>:00</literal> is assumed. If the
 569                                 date component is omitted, the current
 570                                 day is assumed. Alternatively the strings
 571                                 <literal>yesterday</literal>,
 572                                 <literal>today</literal>,
 573                                 <literal>tomorrow</literal> are
 574                                 understood, which refer to 00:00:00 of
 575                                 the day before the current day, the
 576                                 current day, or the day after the
 577                                 current day, respectively. <literal>now</literal>
 578                                 refers to the current time. Finally,
 579                                 relative times may be specified,
 580                                 prefixed with <literal>-</literal> or
 581                                 <literal>+</literal>, referring to
 582                                 times before or after the current
 583                                 time, respectively.</para></listitem>
 584                         </varlistentry>
 585
 586                         <varlistentry>
 587                                 <term><option>-F</option></term>
 588                                 <term><option>--field=</option></term>
 589
 590                                 <listitem><para>Print all possible
 591                                 data values the specified field can
 592                                 take in all entries of the
 593                                 journal.</para></listitem>
 594                         </varlistentry>
 595
 596                         <varlistentry>
 597                                 <term><option>--system</option></term>
 598                                 <term><option>--user</option></term>
 599
 600                                 <listitem><para>Show messages from
 601                                 system services and the kernel (with
 602                                 <option>--system</option>).  Show
 603                                 messages from service of current user
 604                                 (with <option>--user</option>).
 605                                 If neither is specified, show all
 606                                 messages that the user can see.
 607                                 </para></listitem>
 608                         </varlistentry>
 609
 610                         <varlistentry>
 611                                 <term><option>-D <replaceable>DIR</replaceable></option></term>
 612                                 <term><option>--directory=<replaceable>DIR</replaceable></option></term>
 613
 614                                 <listitem><para>Takes a directory path
 615                                 as argument. If specified, journalctl
 616                                 will operate on the specified journal
 617                                 directory
 618                                 <replaceable>DIR</replaceable> instead
 619                                 of the default runtime and system
 620                                 journal paths.</para></listitem>
 621                         </varlistentry>
 622
 623                         <varlistentry>
 624                                 <term><option>--file=<replaceable>GLOB</replaceable></option></term>
 625
 626                                 <listitem><para>Takes a file glob as
 627                                 argument. If specified, journalctl will
 628                                 operate on the specified journal files
 629                                 matching <replaceable>GLOB</replaceable>
 630                                 instead of the default runtime and
 631                                 system journal paths. May be specified
 632                                 multiple times, in which case files will
 633                                 be suitably interleaved.</para></listitem>
 634                         </varlistentry>
 635
 636                         <varlistentry>
 637                                 <term><option>--root=<replaceable>ROOT</replaceable></option></term>
 638
 639                                 <listitem><para>Takes a directory path
 640                                 as argument. If specified, journalctl
 641                                 will operate on catalog file hierarchy
 642                                 underneath the specified directory
 643                                 instead of the root directory
 644                                 (e.g. <option>--update-catalog</option>
 645                                 will create
 646                                 <filename><replaceable>ROOT</replaceable>/var/lib/systemd/catalog/database</filename>).
 647                                 </para></listitem>
 648                         </varlistentry>
 649
 650                         <varlistentry>
 651                                 <term><option>--new-id128</option></term>
 652
 653                                 <listitem><para>Instead of showing
 654                                 journal contents, generate a new 128
 655                                 bit ID suitable for identifying
 656                                 messages. This is intended for usage
 657                                 by developers who need a new
 658                                 identifier for a new message they
 659                                 introduce and want to make
 660                                 recognizable. This will print the new ID in
 661                                 three different formats which can be
 662                                 copied into source code or
 663                                 similar.</para></listitem>
 664                         </varlistentry>
 665
 666                         <varlistentry>
 667                                 <term><option>--header</option></term>
 668
 669                                 <listitem><para>Instead of showing
 670                                 journal contents, show internal header
 671                                 information of the journal fields
 672                                 accessed.</para></listitem>
 673                         </varlistentry>
 674
 675                         <varlistentry>
 676                                 <term><option>--disk-usage</option></term>
 677
 678                                 <listitem><para>Shows the current disk
 679                                 usage of all
 680                                 journal files.</para></listitem>
 681                         </varlistentry>
 682
 683                         <varlistentry>
 684                                 <term><option>--list-catalog
 685                                 <optional><replaceable>ID128...</replaceable></optional>
 686                                 </option></term>
 687
 688                                 <listitem><para>List the contents of
 689                                 the message catalog, as table of
 690                                 message IDs plus their short
 691                                 description strings.</para>
 692
 693                                 <para>If any
 694                                 <replaceable>ID128</replaceable>s are
 695                                 specified, only those entries are shown.
 696                                 </para>
 697                                 </listitem>
 698                         </varlistentry>
 699
 700                         <varlistentry>
 701                                 <term><option>--dump-catalog
 702                                 <optional><replaceable>ID128...</replaceable></optional>
 703                                 </option></term>
 704
 705                                 <listitem><para>Show the contents of
 706                                 the message catalog, with entries
 707                                 separated by a line consisting of two
 708                                 dashes and the id (the format is the
 709                                 same as <filename>.catalog</filename>
 710                                 files.</para>
 711
 712                                 <para>If any
 713                                 <replaceable>ID128</replaceable>s are
 714                                 specified, only those entries are shown.
 715                                 </para>
 716                                 </listitem>
 717                         </varlistentry>
 718
 719                         <varlistentry>
 720                                 <term><option>--update-catalog</option></term>
 721
 722                                 <listitem><para>Update the message
 723                                 catalog index. This command needs to
 724                                 be executed each time new catalog
 725                                 files are installed, removed or
 726                                 updated to rebuild the binary catalog
 727                                 index.</para></listitem>
 728                         </varlistentry>
 729
 730                         <varlistentry>
 731                                 <term><option>--setup-keys</option></term>
 732
 733                                 <listitem><para>Instead of showing
 734                                 journal contents, generate a new key
 735                                 pair for Forward Secure Sealing
 736                                 (FSS). This will generate a sealing
 737                                 key and a verification key. The
 738                                 sealing key is stored in the journal
 739                                 data directory and shall remain on the
 740                                 host. The verification key should be
 741                                 stored externally. Also see the
 742                                 <option>Seal=</option> option in
 743                                 <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 744                                 for details.</para></listitem>
 745                         </varlistentry>
 746
 747                         <varlistentry>
 748                                 <term><option>--force</option></term>
 749
 750                                 <listitem><para>When --setup-keys is passed and
 751                                 Forward Secure Sealing has already been set up,
 752                                 recreate FSS keys.</para></listitem>
 753                         </varlistentry>
 754
 755                         <varlistentry>
 756                                 <term><option>--interval=</option></term>
 757
 758                                 <listitem><para>Specifies the change
 759                                 interval for the sealing key when
 760                                 generating an FSS key pair with
 761                                 <option>--setup-keys</option>. Shorter
 762                                 intervals increase CPU consumption but
 763                                 shorten the time range of
 764                                 undetectable journal
 765                                 alterations. Defaults to
 766                                 15min.</para></listitem>
 767                         </varlistentry>
 768
 769                         <varlistentry>
 770                                 <term><option>--verify</option></term>
 771
 772                                 <listitem><para>Check the journal file
 773                                 for internal consistency. If the
 774                                 file has been generated with FSS
 775                                 enabled and the FSS verification key
 776                                 has been specified with
 777                                 <option>--verify-key=</option>,
 778                                 authenticity of the journal file is
 779                                 verified.</para></listitem>
 780                         </varlistentry>
 781
 782                         <varlistentry>
 783                                 <term><option>--verify-key=</option></term>
 784
 785                                 <listitem><para>Specifies the FSS
 786                                 verification key to use for the
 787                                 <option>--verify</option>
 788                                 operation.</para></listitem>
 789                         </varlistentry>
 790
 791                 </variablelist>
 792         </refsect1>
 793
 794         <refsect1>
 795                 <title>Exit status</title>
 796
 797                 <para>On success, 0 is returned, a non-zero failure
 798                 code otherwise.</para>
 799         </refsect1>
 800
 801         <refsect1>
 802                 <title>Environment</title>
 803
 804                 <variablelist class='environment-variables'>
 805                         <varlistentry>
 806                                 <term><varname>$SYSTEMD_PAGER</varname></term>
 807                                 <listitem><para>Pager to use when
 808                                 <option>--no-pager</option> is not given;
 809                                 overrides <varname>$PAGER</varname>.  Setting
 810                                 this to an empty string or the value
 811                                 <literal>cat</literal> is equivalent to passing
 812                                 <option>--no-pager</option>.</para></listitem>
 813                         </varlistentry>
 814                 </variablelist>
 815         </refsect1>
 816
 817         <refsect1>
 818                 <title>Examples</title>
 819
 820                 <para>Without arguments, all collected logs are shown
 821                 unfiltered:</para>
 822
 823                 <programlisting>journalctl</programlisting>
 824
 825                 <para>With one match specified, all entries with a field matching the expression are shown:</para>
 826
 827                 <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service</programlisting>
 828
 829                 <para>If two different fields are matched, only entries matching both expressions at the same time are shown:</para>
 830
 831                 <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097</programlisting>
 832
 833                 <para>If two matches refer to the same field, all entries matching either expression are shown:</para>
 834
 835                 <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _SYSTEMD_UNIT=dbus.service</programlisting>
 836
 837                 <para>If the separator <literal>+</literal> is used,
 838                 two expressions may be combined in a logical OR. The
 839                 following will show all messages from the Avahi
 840                 service process with the PID 28097 plus all messages
 841                 from the D-Bus service (from any of its
 842                 processes):</para>
 843
 844                 <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097 + _SYSTEMD_UNIT=dbus.service</programlisting>
 845
 846                 <para>Show all logs generated by the D-Bus executable:</para>
 847
 848                 <programlisting>journalctl /usr/bin/dbus-daemon</programlisting>
 849
 850                 <para>Show all logs of the kernel device node <filename noindex='true'>/dev/sda</filename>:</para>
 851
 852                 <programlisting>journalctl /dev/sda</programlisting>
 853
 854                 <para>Show all kernel logs from previous boot:</para>
 855
 856                 <programlisting>journalctl -k -b -1</programlisting>
 857
 858         </refsect1>
 859
 860         <refsect1>
 861                 <title>See Also</title>
 862                 <para>
 863                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 864                         <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 865                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 866                         <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 867                         <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 868                 </para>
 869         </refsect1>
 870
 871 </refentry>