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0a1750934f
It is useful to look at a (possibly inactive) container or other os tree with --root=/path/to/container. This is similar to specifying --directory=/path/to/container/var/log/journal --directory=/path/to/container/run/systemd/journal (if using --directory multiple times was allowed), but doesn't require as much typing.
930 lines
38 KiB
XML
930 lines
38 KiB
XML
<?xml version='1.0'?> <!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!--
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This file is part of systemd.
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Copyright 2012 Lennart Poettering
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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-->
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<refentry id="journalctl"
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xmlns:xi="http://www.w3.org/2001/XInclude">
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<refentryinfo>
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<title>journalctl</title>
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<productname>systemd</productname>
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<authorgroup>
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<author>
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<contrib>Developer</contrib>
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<firstname>Lennart</firstname>
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<surname>Poettering</surname>
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<email>lennart@poettering.net</email>
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</author>
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</authorgroup>
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</refentryinfo>
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<refmeta>
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<refentrytitle>journalctl</refentrytitle>
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<manvolnum>1</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>journalctl</refname>
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<refpurpose>Query the systemd journal</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<cmdsynopsis>
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<command>journalctl</command>
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<arg choice="opt" rep="repeat">OPTIONS</arg>
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<arg choice="opt" rep="repeat">MATCHES</arg>
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</cmdsynopsis>
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</refsynopsisdiv>
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<refsect1>
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<title>Description</title>
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<para><command>journalctl</command> may be used to query the
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contents of the
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<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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journal as written by
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<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
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<para>If called without parameters, it will show the full
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contents of the journal, starting with the oldest entry
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collected.</para>
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<para>If one or more match arguments are passed, the output is
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filtered accordingly. A match is in the format
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<literal>FIELD=VALUE</literal>,
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e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>, referring
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to the components of a structured journal entry. See
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<citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>
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for a list of well-known fields. If multiple matches are
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specified matching different fields, the log entries are
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filtered by both, i.e. the resulting output will show only
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entries matching all the specified matches of this kind. If two
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matches apply to the same field, then they are automatically
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matched as alternatives, i.e. the resulting output will show
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entries matching any of the specified matches for the same
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field. Finally, the character <literal>+</literal> may appear
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as a separate word between other terms on the command line. This
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causes all matches before and after to be combined in a
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disjunction (i.e. logical OR).</para>
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<para>It is also possible to filter the entries by specifying an
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absolute file path as an argument. The file path may be a file or
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a symbolic link and the file must exist at the time of the query. If a
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file path refers to an executable binary, an <literal>_EXE=</literal>
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match for the canonicalized binary path is added to the query. If a
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file path refers to an executable script, a <literal>_COMM=</literal>
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match for the script name is added to the query. If a file path
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refers to a device node, <literal>_KERNEL_DEVICE=</literal> matches for
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the kernel name of the device and for each of its ancestor devices is
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added to the query. Symbolic links are dereferenced, kernel names are
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synthesized, and parent devices are identified from the environment at
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the time of the query. In general, a device node is the best proxy for
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an actual device, as log entries do not usually contain fields that
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identify an actual device. For the resulting log entries to be correct
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for the actual device, the relevant parts of the environment at the time
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the entry was logged, in particular the actual device corresponding to
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the device node, must have been the same as those at the time of the
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query. Because device nodes generally change their corresponding devices
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across reboots, specifying a device node path causes the resulting
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entries to be restricted to those from the current boot.</para>
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<para>Additional constraints may be added using options
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<option>--boot</option>, <option>--unit=</option>, etc., to
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further limit what entries will be shown (logical AND).</para>
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<para>Output is interleaved from all accessible journal files,
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whether they are rotated or currently being written, and
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regardless of whether they belong to the system itself or are
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accessible user journals.</para>
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<para>The set of journal files which will be used can be
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modified using the <option>--user</option>,
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<option>--system</option>, <option>--directory</option>, and
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<option>--file</option> options, see below.</para>
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<para>All users are granted access to their private per-user
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journals. However, by default, only root and users who are
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members of a few special groups are granted access to the system
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journal and the journals of other users. Members of the groups
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<literal>systemd-journal</literal>, <literal>adm</literal>, and
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<literal>wheel</literal> can read all journal files. Note
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that the two latter groups traditionally have additional
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privileges specified by the distribution. Members of the
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<literal>wheel</literal> group can often perform administrative
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tasks.</para>
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<para>The output is paged through <command>less</command> by
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default, and long lines are "truncated" to screen width. The
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hidden part can be viewed by using the left-arrow and
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right-arrow keys. Paging can be disabled; see the
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<option>--no-pager</option> option and the "Environment" section
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below.</para>
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<para>When outputting to a tty, lines are colored according to
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priority: lines of level ERROR and higher are colored red; lines
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of level NOTICE and higher are highlighted; other lines are
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displayed normally.</para>
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</refsect1>
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<refsect1>
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<title>Options</title>
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<para>The following options are understood:</para>
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<variablelist>
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<varlistentry>
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<term><option>--no-full</option></term>
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<term><option>--full</option></term>
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<term><option>-l</option></term>
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<listitem><para>Ellipsize fields when they do not fit in
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available columns. The default is to show full fields,
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allowing them to wrap or be truncated by the pager, if one
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is used.</para>
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<para>The old options
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<option>-l</option>/<option>--full</option> are not useful
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anymore, except to undo <option>--no-full</option>.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-a</option></term>
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<term><option>--all</option></term>
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<listitem><para>Show all fields in full, even if they
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include unprintable characters or are very
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long.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-f</option></term>
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<term><option>--follow</option></term>
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<listitem><para>Show only the most recent journal entries,
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and continuously print new entries as they are appended to
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the journal.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-e</option></term>
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<term><option>--pager-end</option></term>
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<listitem><para>Immediately jump to the end of the journal
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inside the implied pager tool. This implies
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<option>-n1000</option> to guarantee that the pager will not
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buffer logs of unbounded size. This may be overridden with
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an explicit <option>-n</option> with some other numeric
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value, while <option>-nall</option> will disable this cap.
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Note that this option is only supported for the
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<citerefentry project='man-pages'><refentrytitle>less</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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pager.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-n</option></term>
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<term><option>--lines=</option></term>
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<listitem><para>Show the most recent journal events and
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limit the number of events shown. If
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<option>--follow</option> is used, this option is
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implied. The argument is a positive integer or
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<literal>all</literal> to disable line limiting. The default
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value is 10 if no argument is given.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--no-tail</option></term>
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<listitem><para>Show all stored output lines, even in follow
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mode. Undoes the effect of <option>--lines=</option>.
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</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-r</option></term>
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<term><option>--reverse</option></term>
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<listitem><para>Reverse output so that the newest entries
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are displayed first.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-o</option></term>
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<term><option>--output=</option></term>
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<listitem><para>Controls the formatting of the journal
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entries that are shown. Takes one of the following
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options:</para>
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<variablelist>
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<varlistentry>
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<term>
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<option>short</option>
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</term>
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<listitem>
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<para>is the default and generates an output that is
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mostly identical to the formatting of classic syslog
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files, showing one line per journal entry.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>short-full</option>
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</term>
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<listitem>
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<para>is very similar, but shows timestamps in the format the <option>--since=</option> and
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<option>--until=</option> options accept. Unlike the timestamp information shown in
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<option>short</option> output mode this mode includes weekday, year and timezone information in the
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output, and is locale-independent.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>short-iso</option>
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</term>
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<listitem>
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<para>is very similar, but shows ISO 8601 wallclock
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timestamps.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>short-precise</option>
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</term>
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<listitem>
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<para>is very similar, but shows timestamps with full
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microsecond precision.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>short-monotonic</option>
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</term>
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<listitem>
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<para>is very similar, but shows monotonic timestamps
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instead of wallclock timestamps.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>short-unix</option>
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</term>
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<listitem>
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<para>is very similar, but shows seconds passed since January 1st 1970 UTC instead of wallclock
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timestamps ("UNIX time"). The time is shown with microsecond accuracy.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>verbose</option>
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</term>
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<listitem>
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<para>shows the full-structured entry items with all
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fields.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>export</option>
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</term>
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<listitem>
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<para>serializes the journal into a binary (but mostly
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text-based) stream suitable for backups and network
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transfer (see
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<ulink url="http://www.freedesktop.org/wiki/Software/systemd/export">Journal Export Format</ulink>
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for more information).</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>json</option>
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</term>
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<listitem>
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<para>formats entries as JSON data structures, one per
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line (see
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<ulink url="http://www.freedesktop.org/wiki/Software/systemd/json">Journal JSON Format</ulink>
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for more information).</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>json-pretty</option>
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</term>
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<listitem>
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<para>formats entries as JSON data structures, but
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formats them in multiple lines in order to make them
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more readable by humans.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>json-sse</option>
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</term>
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<listitem>
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<para>formats entries as JSON data structures, but wraps
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them in a format suitable for
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<ulink url="https://developer.mozilla.org/en-US/docs/Server-sent_events/Using_server-sent_events">Server-Sent Events</ulink>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>
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<option>cat</option>
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</term>
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<listitem>
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<para>generates a very terse output, only showing the
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actual message of each journal entry with no metadata,
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not even a timestamp.</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--utc</option></term>
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<listitem><para>Express time in Coordinated Universal Time
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(UTC).</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--no-hostname</option></term>
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<listitem><para>Don't show the hostname field of log messages originating from the local host. This switch only
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has an effect on the <option>short</option> family of output modes (see above).</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-x</option></term>
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<term><option>--catalog</option></term>
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<listitem><para>Augment log lines with explanation texts from
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the message catalog. This will add explanatory help texts to
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log messages in the output where this is available. These
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short help texts will explain the context of an error or log
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event, possible solutions, as well as pointers to support
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forums, developer documentation, and any other relevant
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manuals. Note that help texts are not available for all
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messages, but only for selected ones. For more information on
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the message catalog, please refer to the
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<ulink url="http://www.freedesktop.org/wiki/Software/systemd/catalog">Message Catalog Developer Documentation</ulink>.</para>
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<para>Note: when attaching <command>journalctl</command>
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output to bug reports, please do <emphasis>not</emphasis> use
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<option>-x</option>.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-q</option></term>
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<term><option>--quiet</option></term>
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<listitem><para>Suppresses all info messages
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(i.e. "-- Logs begin at ...", "-- Reboot --"),
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any warning messages regarding
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inaccessible system journals when run as a normal
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user.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-m</option></term>
|
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<term><option>--merge</option></term>
|
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|
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<listitem><para>Show entries interleaved from all available
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journals, including remote ones.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>-b <optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional></option></term>
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||
<term><option>--boot=<optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional></option></term>
|
||
|
||
<listitem><para>Show messages from a specific boot. This will
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||
add a match for <literal>_BOOT_ID=</literal>.</para>
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||
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||
<para>The argument may be empty, in which case logs for the
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current boot will be shown.</para>
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<para>If the boot ID is omitted, a positive
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<replaceable>offset</replaceable> will look up the boots
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starting from the beginning of the journal, and an
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equal-or-less-than zero <replaceable>offset</replaceable> will
|
||
look up boots starting from the end of the journal. Thus,
|
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<constant>1</constant> means the first boot found in the
|
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journal in chronological order, <constant>2</constant> the
|
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second and so on; while <constant>-0</constant> is the last
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||
boot, <constant>-1</constant> the boot before last, and so
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||
on. An empty <replaceable>offset</replaceable> is equivalent
|
||
to specifying <constant>-0</constant>, except when the current
|
||
boot is not the last boot (e.g. because
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||
<option>--directory</option> was specified to look at logs
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||
from a different machine).</para>
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||
|
||
<para>If the 32-character <replaceable>ID</replaceable> is
|
||
specified, it may optionally be followed by
|
||
<replaceable>offset</replaceable> which identifies the boot
|
||
relative to the one given by boot
|
||
<replaceable>ID</replaceable>. Negative values mean earlier
|
||
boots and positive values mean later boots. If
|
||
<replaceable>offset</replaceable> is not specified, a value of
|
||
zero is assumed, and the logs for the boot given by
|
||
<replaceable>ID</replaceable> are shown.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--list-boots</option></term>
|
||
|
||
<listitem><para>Show a tabular list of boot numbers (relative to
|
||
the current boot), their IDs, and the timestamps of the first
|
||
and last message pertaining to the boot.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-k</option></term>
|
||
<term><option>--dmesg</option></term>
|
||
|
||
<listitem><para>Show only kernel messages. This implies
|
||
<option>-b</option> and adds the match
|
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<literal>_TRANSPORT=kernel</literal>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-t</option></term>
|
||
<term><option>--identifier=<replaceable>SYSLOG_IDENTIFIER</replaceable></option></term>
|
||
|
||
<listitem><para>Show messages for the specified syslog
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||
identifier
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||
<replaceable>SYSLOG_IDENTIFIER</replaceable>.</para>
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|
||
<para>This parameter can be specified multiple
|
||
times.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-u</option></term>
|
||
<term><option>--unit=<replaceable>UNIT</replaceable>|<replaceable>PATTERN</replaceable></option></term>
|
||
|
||
<listitem><para>Show messages for the specified systemd unit
|
||
<replaceable>UNIT</replaceable> (such as a service unit), or
|
||
for any of the units matched by
|
||
<replaceable>PATTERN</replaceable>. If a pattern is
|
||
specified, a list of unit names found in the journal is
|
||
compared with the specified pattern and all that match are
|
||
used. For each unit name, a match is added for messages from
|
||
the unit
|
||
(<literal>_SYSTEMD_UNIT=<replaceable>UNIT</replaceable></literal>),
|
||
along with additional matches for messages from systemd and
|
||
messages about coredumps for the specified unit.</para>
|
||
|
||
<para>This parameter can be specified multiple times.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--user-unit=</option></term>
|
||
|
||
<listitem><para>Show messages for the specified user session
|
||
unit. This will add a match for messages from the unit
|
||
(<literal>_SYSTEMD_USER_UNIT=</literal> and
|
||
<literal>_UID=</literal>) and additional matches for messages
|
||
from session systemd and messages about coredumps for the
|
||
specified unit.</para>
|
||
|
||
<para>This parameter can be specified multiple times.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-p</option></term>
|
||
<term><option>--priority=</option></term>
|
||
|
||
<listitem><para>Filter output by message priorities or
|
||
priority ranges. Takes either a single numeric or textual log
|
||
level (i.e. between 0/<literal>emerg</literal> and
|
||
7/<literal>debug</literal>), or a range of numeric/text log
|
||
levels in the form FROM..TO. The log levels are the usual
|
||
syslog log levels as documented in
|
||
<citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
||
i.e. <literal>emerg</literal> (0),
|
||
<literal>alert</literal> (1), <literal>crit</literal> (2),
|
||
<literal>err</literal> (3), <literal>warning</literal> (4),
|
||
<literal>notice</literal> (5), <literal>info</literal> (6),
|
||
<literal>debug</literal> (7). If a single log level is
|
||
specified, all messages with this log level or a lower (hence
|
||
more important) log level are shown. If a range is specified,
|
||
all messages within the range are shown, including both the
|
||
start and the end value of the range. This will add
|
||
<literal>PRIORITY=</literal> matches for the specified
|
||
priorities.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-c</option></term>
|
||
<term><option>--cursor=</option></term>
|
||
|
||
<listitem><para>Start showing entries from the location in the
|
||
journal specified by the passed cursor.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--after-cursor=</option></term>
|
||
|
||
<listitem><para>Start showing entries from the location in the
|
||
journal <emphasis>after</emphasis> the location specified by
|
||
the passed cursor. The cursor is shown when the
|
||
<option>--show-cursor</option> option is used.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--show-cursor</option></term>
|
||
|
||
<listitem><para>The cursor is shown after the last entry after
|
||
two dashes:</para>
|
||
<programlisting>-- cursor: s=0639...</programlisting>
|
||
<para>The format of the cursor is private
|
||
and subject to change.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-S</option></term>
|
||
<term><option>--since=</option></term>
|
||
<term><option>-U</option></term>
|
||
<term><option>--until=</option></term>
|
||
|
||
<listitem><para>Start showing entries on or newer than the specified date, or on or older than the specified
|
||
date, respectively. Date specifications should be of the format <literal>2012-10-30 18:17:16</literal>. If the
|
||
time part is omitted, <literal>00:00:00</literal> is assumed. If only the seconds component is omitted,
|
||
<literal>:00</literal> is assumed. If the date component is omitted, the current day is assumed. Alternatively
|
||
the strings <literal>yesterday</literal>, <literal>today</literal>, <literal>tomorrow</literal> are understood,
|
||
which refer to 00:00:00 of the day before the current day, the current day, or the day after the current day,
|
||
respectively. <literal>now</literal> refers to the current time. Finally, relative times may be specified,
|
||
prefixed with <literal>-</literal> or <literal>+</literal>, referring to times before or after the current
|
||
time, respectively. For complete time and date specification, see
|
||
<citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>. Note that
|
||
<option>--output=short-full</option> prints timestamps that follow precisely this format.
|
||
</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-F</option></term>
|
||
<term><option>--field=</option></term>
|
||
|
||
<listitem><para>Print all possible data values the specified
|
||
field can take in all entries of the journal.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-N</option></term>
|
||
<term><option>--fields</option></term>
|
||
|
||
<listitem><para>Print all field names currently used in all entries of the journal.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--system</option></term>
|
||
<term><option>--user</option></term>
|
||
|
||
<listitem><para>Show messages from system services and the
|
||
kernel (with <option>--system</option>). Show messages from
|
||
service of current user (with <option>--user</option>). If
|
||
neither is specified, show all messages that the user can see.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-M</option></term>
|
||
<term><option>--machine=</option></term>
|
||
|
||
<listitem><para>Show messages from a running, local
|
||
container. Specify a container name to connect to.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>-D <replaceable>DIR</replaceable></option></term>
|
||
<term><option>--directory=<replaceable>DIR</replaceable></option></term>
|
||
|
||
<listitem><para>Takes a directory path as argument. If
|
||
specified, journalctl will operate on the specified journal
|
||
directory <replaceable>DIR</replaceable> instead of the
|
||
default runtime and system journal paths.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--file=<replaceable>GLOB</replaceable></option></term>
|
||
|
||
<listitem><para>Takes a file glob as an argument. If
|
||
specified, journalctl will operate on the specified journal
|
||
files matching <replaceable>GLOB</replaceable> instead of the
|
||
default runtime and system journal paths. May be specified
|
||
multiple times, in which case files will be suitably
|
||
interleaved.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--root=<replaceable>ROOT</replaceable></option></term>
|
||
|
||
<listitem><para>Takes a directory path as an argument. If
|
||
specified, journalctl will operate on journal directories and catalog file hierarchy
|
||
underneath the specified directory instead of the root
|
||
directory (e.g. <option>--update-catalog</option> will create
|
||
<filename><replaceable>ROOT</replaceable>/var/lib/systemd/catalog/database</filename>,
|
||
and journal files under <filename><replaceable>ROOT</replaceable>/run/journal</filename>
|
||
or <filename><replaceable>ROOT</replaceable>/var/log/journal</filename> will be displayed).
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--new-id128</option></term>
|
||
|
||
<listitem><para>Instead of showing journal contents, generate
|
||
a new 128-bit ID suitable for identifying messages. This is
|
||
intended for usage by developers who need a new identifier for
|
||
a new message they introduce and want to make
|
||
recognizable. This will print the new ID in three different
|
||
formats which can be copied into source code or similar.
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--header</option></term>
|
||
|
||
<listitem><para>Instead of showing journal contents, show
|
||
internal header information of the journal fields
|
||
accessed.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--disk-usage</option></term>
|
||
|
||
<listitem><para>Shows the current disk usage of all journal
|
||
files. This shows the sum of the disk usage of all archived
|
||
and active journal files.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--vacuum-size=</option></term>
|
||
<term><option>--vacuum-time=</option></term>
|
||
<term><option>--vacuum-files=</option></term>
|
||
|
||
<listitem><para>Removes archived journal files until the disk
|
||
space they use falls below the specified size (specified with
|
||
the usual <literal>K</literal>, <literal>M</literal>,
|
||
<literal>G</literal> and <literal>T</literal> suffixes), or all
|
||
archived journal files contain no data older than the specified
|
||
timespan (specified with the usual <literal>s</literal>,
|
||
<literal>m</literal>, <literal>h</literal>,
|
||
<literal>days</literal>, <literal>months</literal>,
|
||
<literal>weeks</literal> and <literal>years</literal> suffixes),
|
||
or no more than the specified number of separate journal files
|
||
remain. Note that running <option>--vacuum-size=</option> has
|
||
only an indirect effect on the output shown by
|
||
<option>--disk-usage</option>, as the latter includes active
|
||
journal files, while the vacuuming operation only operates
|
||
on archived journal files. Similarly,
|
||
<option>--vacuum-files=</option> might not actually reduce the
|
||
number of journal files to below the specified number, as it
|
||
will not remove active journal
|
||
files. <option>--vacuum-size=</option>,
|
||
<option>--vacuum-time=</option> and
|
||
<option>--vacuum-files=</option> may be combined in a single
|
||
invocation to enforce any combination of a size, a time and a
|
||
number of files limit on the archived journal
|
||
files. Specifying any of these three parameters as zero is
|
||
equivalent to not enforcing the specific limit, and is thus
|
||
redundant.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--list-catalog
|
||
<optional><replaceable>128-bit-ID...</replaceable></optional>
|
||
</option></term>
|
||
|
||
<listitem><para>List the contents of the message catalog as a
|
||
table of message IDs, plus their short description strings.
|
||
</para>
|
||
|
||
<para>If any <replaceable>128-bit-ID</replaceable>s are
|
||
specified, only those entries are shown.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--dump-catalog
|
||
<optional><replaceable>128-bit-ID...</replaceable></optional>
|
||
</option></term>
|
||
|
||
<listitem><para>Show the contents of the message catalog, with
|
||
entries separated by a line consisting of two dashes and the
|
||
ID (the format is the same as <filename>.catalog</filename>
|
||
files).</para>
|
||
|
||
<para>If any <replaceable>128-bit-ID</replaceable>s are
|
||
specified, only those entries are shown.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--update-catalog</option></term>
|
||
|
||
<listitem><para>Update the message catalog index. This command
|
||
needs to be executed each time new catalog files are
|
||
installed, removed, or updated to rebuild the binary catalog
|
||
index.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--setup-keys</option></term>
|
||
|
||
<listitem><para>Instead of showing journal contents, generate
|
||
a new key pair for Forward Secure Sealing (FSS). This will
|
||
generate a sealing key and a verification key. The sealing key
|
||
is stored in the journal data directory and shall remain on
|
||
the host. The verification key should be stored
|
||
externally. Refer to the <option>Seal=</option> option in
|
||
<citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
||
for information on Forward Secure Sealing and for a link to a
|
||
refereed scholarly paper detailing the cryptographic theory it
|
||
is based on.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--force</option></term>
|
||
|
||
<listitem><para>When <option>--setup-keys</option> is passed
|
||
and Forward Secure Sealing (FSS) has already been configured,
|
||
recreate FSS keys.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--interval=</option></term>
|
||
|
||
<listitem><para>Specifies the change interval for the sealing
|
||
key when generating an FSS key pair with
|
||
<option>--setup-keys</option>. Shorter intervals increase CPU
|
||
consumption but shorten the time range of undetectable journal
|
||
alterations. Defaults to 15min.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--verify</option></term>
|
||
|
||
<listitem><para>Check the journal file for internal
|
||
consistency. If the file has been generated with FSS enabled and
|
||
the FSS verification key has been specified with
|
||
<option>--verify-key=</option>, authenticity of the journal file
|
||
is verified.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--verify-key=</option></term>
|
||
|
||
<listitem><para>Specifies the FSS verification key to use for
|
||
the <option>--verify</option> operation.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--sync</option></term>
|
||
|
||
<listitem><para>Asks the journal daemon to write all yet
|
||
unwritten journal data to the backing file system and
|
||
synchronize all journals. This call does not return until the
|
||
synchronization operation is complete. This command guarantees
|
||
that any log messages written before its invocation are safely
|
||
stored on disk at the time it returns.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--flush</option></term>
|
||
|
||
<listitem><para>Asks the journal daemon to flush any log data
|
||
stored in <filename>/run/log/journal</filename> into
|
||
<filename>/var/log/journal</filename>, if persistent storage
|
||
is enabled. This call does not return until the operation is
|
||
complete. Note that this call is idempotent: the data is only
|
||
flushed from <filename>/run/log/journal</filename> into
|
||
<filename>/var/log/journal</filename> once during system
|
||
runtime, and this command exits cleanly without executing any
|
||
operation if this has already happened. This command
|
||
effectively guarantees that all data is flushed to
|
||
<filename>/var/log/journal</filename> at the time it
|
||
returns.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--rotate</option></term>
|
||
|
||
<listitem><para>Asks the journal daemon to rotate journal
|
||
files. This call does not return until the rotation operation
|
||
is complete.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
<xi:include href="standard-options.xml" xpointer="version" />
|
||
<xi:include href="standard-options.xml" xpointer="no-pager" />
|
||
</variablelist>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Exit status</title>
|
||
|
||
<para>On success, 0 is returned; otherwise, a non-zero failure
|
||
code is returned.</para>
|
||
</refsect1>
|
||
|
||
<xi:include href="less-variables.xml" />
|
||
|
||
<refsect1>
|
||
<title>Examples</title>
|
||
|
||
<para>Without arguments, all collected logs are shown
|
||
unfiltered:</para>
|
||
|
||
<programlisting>journalctl</programlisting>
|
||
|
||
<para>With one match specified, all entries with a field matching
|
||
the expression are shown:</para>
|
||
|
||
<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service</programlisting>
|
||
|
||
<para>If two different fields are matched, only entries matching
|
||
both expressions at the same time are shown:</para>
|
||
|
||
<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097</programlisting>
|
||
|
||
<para>If two matches refer to the same field, all entries matching
|
||
either expression are shown:</para>
|
||
|
||
<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _SYSTEMD_UNIT=dbus.service</programlisting>
|
||
|
||
<para>If the separator <literal>+</literal> is used, two
|
||
expressions may be combined in a logical OR. The following will
|
||
show all messages from the Avahi service process with the PID
|
||
28097 plus all messages from the D-Bus service (from any of its
|
||
processes):</para>
|
||
|
||
<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097 + _SYSTEMD_UNIT=dbus.service</programlisting>
|
||
|
||
<para>Show all logs generated by the D-Bus executable:</para>
|
||
|
||
<programlisting>journalctl /usr/bin/dbus-daemon</programlisting>
|
||
|
||
<para>Show all kernel logs from previous boot:</para>
|
||
|
||
<programlisting>journalctl -k -b -1</programlisting>
|
||
|
||
<para>Show a live log display from a system service
|
||
<filename>apache.service</filename>:</para>
|
||
|
||
<programlisting>journalctl -f -u apache</programlisting>
|
||
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>See Also</title>
|
||
<para>
|
||
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>coredumpctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
||
<citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
||
</para>
|
||
</refsect1>
|
||
</refentry>
|