[thirdparty/systemd.git] / man / journalctl.xml

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  systemd is free software; you can redistribute it and/or modify it
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<refentry id="journalctl">

        <refentryinfo>
                <title>journalctl</title>
                <productname>systemd</productname>

                <authorgroup>
                        <author>
                                <contrib>Developer</contrib>
                                <firstname>Lennart</firstname>
                                <surname>Poettering</surname>
                                <email>lennart@poettering.net</email>
                        </author>
                </authorgroup>
        </refentryinfo>

        <refmeta>
                <refentrytitle>journalctl</refentrytitle>
                <manvolnum>1</manvolnum>
        </refmeta>

        <refnamediv>
                <refname>journalctl</refname>
                <refpurpose>Query the systemd journal</refpurpose>
        </refnamediv>

        <refsynopsisdiv>
                <cmdsynopsis>
                        <command>journalctl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt" rep="repeat">MATCHES</arg></command>
                </cmdsynopsis>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para><command>journalctl</command> may be used to
                query the contents of the
                <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
                journal as written by
                <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

                <para>If called without parameter will show the full
                contents of the journal, starting with the oldest
                entry collected.</para>

                <para>If one or more match arguments are passed the
                output is filtered accordingly. A match is in the
                format <literal>FIELD=VALUE</literal>,
                e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>,
                referring to the components of a structured journal
                entry. See
                <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                for a list of well-known fields. If multiple matches
                are specified matching different fields the log
                entries are filtered by both, i.e. the resulting output
                will show only entries matching all the specified
                matches of this kind. If two matches apply to the same
                field, then they are automatically matched as
                alternatives, i.e. the resulting output will show
                entries matching any of the specified matches for the
                same field. Finally, if the character
                "<literal>+</literal>" appears as separate word on the
                command line all matches before and after are combined
                in a disjunction (i.e. logical OR).</para>

                <para>As shortcuts for a few types of field/value
                matches file paths may be specified. If a file path
                refers to an executable file, this is equivalent to an
                <literal>_EXE=</literal> match for the canonicalized
                binary path. Similar, if a path refers to a device
                node, this is equivalent to a
                <literal>_KERNEL_DEVICE=</literal> match for the
                device.</para>

                <para>Output is interleaved from all accessible
                journal files, whether they are rotated or currently
                being written, and regardless whether they belong to the
                system itself or are accessible user journals.</para>

                <para>All users are granted access to their private
                per-user journals. However, by default only root and
                users who are members of the <literal>adm</literal>
                group get access to the system journal and the
                journals of other users.</para>
        </refsect1>

        <refsect1>
                <title>Options</title>

                <para>The following options are understood:</para>

                <variablelist>
                        <varlistentry>
                                <term><option>--help</option></term>
                                <term><option>-h</option></term>

                                <listitem><para>Prints a short help
                                text and exits.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--version</option></term>

                                <listitem><para>Prints a short version
                                string and exits.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--no-pager</option></term>

                                <listitem><para>Do not pipe output into a
                                pager.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--all</option></term>
                                <term><option>-a</option></term>

                                <listitem><para>Show all fields in
                                full, even if they include unprintable
                                characters or are very
                                long.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--follow</option></term>
                                <term><option>-f</option></term>

                                <listitem><para>Show only most recent
                                journal entries, and continuously print
                                new entries as they are appended to
                                the journal.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--lines=</option></term>
                                <term><option>-n</option></term>

                                <listitem><para>Controls the number of
                                journal lines to show, counting from
                                the most recent ones. Takes a positive
                                integer argument. In follow mode
                                defaults to 10, otherwise is unset
                                thus not limiting how many lines are
                                shown.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--no-tail</option></term>

                                <listitem><para>Show all stored output
                                lines, even in follow mode. Undoes the
                                effect of
                                <option>--lines=</option>.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--output=</option></term>
                                <term><option>-o</option></term>

                                <listitem><para>Controls the
                                formatting of the journal entries that
                                are shown. Takes one of
                                <literal>short</literal>,
                                <literal>short-monotonic</literal>,
                                <literal>verbose</literal>,
                                <literal>export</literal>,
                                <literal>json</literal>,
                                <literal>json-pretty</literal>,
                                <literal>cat</literal>. <literal>short</literal>
                                is the default and generates an output
                                that is mostly identical to the
                                formatting of classic syslog log
                                files, showing one line per journal
                                entry. <literal>short-monotonic</literal>
                                is very similar but shows monotonic
                                timestamps instead of wallclock
                                timestamps. <literal>verbose</literal>
                                shows the full structured entry items
                                with all
                                fields. <literal>export</literal>
                                serializes the journal into a binary
                                (but mostly text-based) stream
                                suitable for backups and network
                                transfer (see <ulink
                                url="http://www.freedesktop.org/wiki/Software/systemd/export">Journal
                                Export Format</ulink> for more
                                information). <literal>json</literal>
                                formats entries as JSON data
                                structures, one per
                                line. <literal>json-pretty</literal>
                                also formats entries as JSON data
                                structures, but formats them in
                                multiple lines in order to make them
                                more readable for
                                humans. <literal>cat</literal>
                                generates a very terse output only
                                showing the actual message of each
                                journal entry with no meta data, not
                                even a timestamp.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--quiet</option></term>
                                <term><option>-q</option></term>

                                <listitem><para>Suppresses any warning
                                message regarding inaccessible system
                                journals when run as normal
                                user.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--merge</option></term>
                                <term><option>-m</option></term>

                                <listitem><para>Show entries
                                interleaved from all available
                                journals, including remote
                                ones.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--this-boot</option></term>
                                <term><option>-b</option></term>

                                <listitem><para>Show data only from
                                current boot.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--directory=</option></term>
                                <term><option>-D</option></term>

                                <listitem><para>Takes an absolute
                                directory path as argument. If
                                specified will operate on the
                                specified journal directory instead of
                                the default runtime and system journal
                                paths.</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><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 levels 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.</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. 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 fiels
                                accessed.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><option>--disk-usage</option></term>

                                <listitem><para>Shows the current disk
                                usage of all
                                journal files.</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.</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>

                </variablelist>
        </refsect1>

        <refsect1>
                <title>Exit status</title>

                <para>On success 0 is returned, a non-zero failure
                code otherwise.</para>
        </refsect1>

        <refsect1>
                <title>Environment</title>

                <variablelist>
                        <varlistentry>
                                <term><varname>$SYSTEMD_PAGER</varname></term>
                                <listitem><para>Pager to use when
                                <option>--no-pager</option> is not given;
                                overrides <varname>$PAGER</varname>.  Setting
                                this to an empty string or the value
                                <literal>cat</literal> is equivalent to passing
                                <option>--no-pager</option>.</para></listitem>
                        </varlistentry>
                </variablelist>
        </refsect1>

        <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 expression 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 logs of the kernel device node <filename>/dev/sda</filename>:</para>

                <programlisting>journalctl /dev/sda</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>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                </para>
        </refsect1>

</refentry>
Commit	Line	Data
2af777ba LP	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
5430f7f2 LP	11	under the terms of the GNU Lesser General Public License as published by
5430f7f2 LP	12	the Free Software Foundation; either version 2.1 of the License, or
2af777ba LP	13	(at your option) any later version.
	14
	15	systemd is distributed in the hope that it will be useful, but
	16	WITHOUT ANY WARRANTY; without even the implied warranty of
	17	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
5430f7f2	18	Lesser General Public License for more details.
2af777ba	19
5430f7f2	20	You should have received a copy of the GNU Lesser General Public License
2af777ba LP	21	along with systemd; If not, see <http://www.gnu.org/licenses/>.
	22	-->
	23
169c4f65	24	<refentry id="journalctl">
2af777ba LP	25
2af777ba LP	26	<refentryinfo>
169c4f65	27	<title>journalctl</title>
2af777ba LP	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>
169c4f65	41	<refentrytitle>journalctl</refentrytitle>
2af777ba LP	42	<manvolnum>1</manvolnum>
	43	</refmeta>
	44
	45	<refnamediv>
169c4f65	46	<refname>journalctl</refname>
2af777ba LP	47	<refpurpose>Query the systemd journal</refpurpose>
	48	</refnamediv>
	49
	50	<refsynopsisdiv>
	51	<cmdsynopsis>
cbdca852	52	<command>journalctl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt" rep="repeat">MATCHES</arg></command>
2af777ba LP	53	</cmdsynopsis>
	54	</refsynopsisdiv>
	55
	56	<refsect1>
	57	<title>Description</title>
	58
01cf0ca8 LP	59	<para><command>journalctl</command> may be used to
01cf0ca8 LP	60	query the contents of the
2af777ba	61	<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
01cf0ca8 LP	62	journal as written by
01cf0ca8 LP	63	<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
2af777ba LP	64
	65	<para>If called without parameter will show the full
	66	contents of the journal, starting with the oldest
	67	entry collected.</para>
	68
cbdca852 LP	69	<para>If one or more match arguments are passed the
	70	output is filtered accordingly. A match is in the
	71	format <literal>FIELD=VALUE</literal>,
	72	e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>,
	73	referring to the components of a structured journal
	74	entry. See
ffa16db0	75	<citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>
cbdca852 LP	76	for a list of well-known fields. If multiple matches
	77	are specified matching different fields the log
	78	entries are filtered by both, i.e. the resulting output
	79	will show only entries matching all the specified
	80	matches of this kind. If two matches apply to the same
	81	field, then they are automatically matched as
	82	alternatives, i.e. the resulting output will show
	83	entries matching any of the specified matches for the
	84	same field. Finally, if the character
	85	"<literal>+</literal>" appears as separate word on the
	86	command line all matches before and after are combined
	87	in a disjunction (i.e. logical OR).</para>
2af777ba	88
b6a34514 LP	89	<para>As shortcuts for a few types of field/value
	90	matches file paths may be specified. If a file path
	91	refers to an executable file, this is equivalent to an
	92	<literal>_EXE=</literal> match for the canonicalized
	93	binary path. Similar, if a path refers to a device
	94	node, this is equivalent to a
	95	<literal>_KERNEL_DEVICE=</literal> match for the
	96	device.</para>
	97
2af777ba LP	98	<para>Output is interleaved from all accessible
	99	journal files, whether they are rotated or currently
	100	being written, and regardless whether they belong to the
	101	system itself or are accessible user journals.</para>
	102
	103	<para>All users are granted access to their private
	104	per-user journals. However, by default only root and
	105	users who are members of the <literal>adm</literal>
	106	group get access to the system journal and the
	107	journals of other users.</para>
	108	</refsect1>
	109
	110	<refsect1>
	111	<title>Options</title>
	112
	113	<para>The following options are understood:</para>
	114
	115	<variablelist>
	116	<varlistentry>
	117	<term><option>--help</option></term>
	118	<term><option>-h</option></term>
	119
	120	<listitem><para>Prints a short help
	121	text and exits.</para></listitem>
	122	</varlistentry>
	123
	124	<varlistentry>
	125	<term><option>--version</option></term>
	126
	127	<listitem><para>Prints a short version
	128	string and exits.</para></listitem>
	129	</varlistentry>
	130
	131	<varlistentry>
	132	<term><option>--no-pager</option></term>
	133
0e25e94e KS	134	<listitem><para>Do not pipe output into a
	135	pager.</para></listitem>
	136	</varlistentry>
2af777ba LP	137
	138	<varlistentry>
	139	<term><option>--all</option></term>
	140	<term><option>-a</option></term>
	141
	142	<listitem><para>Show all fields in
	143	full, even if they include unprintable
	144	characters or are very
	145	long.</para></listitem>
	146	</varlistentry>
	147
	148	<varlistentry>
	149	<term><option>--follow</option></term>
	150	<term><option>-f</option></term>
	151
	152	<listitem><para>Show only most recent
49f43d5f	153	journal entries, and continuously print
5c3246b1 LP	154	new entries as they are appended to
5c3246b1 LP	155	the journal.</para></listitem>
2af777ba LP	156	</varlistentry>
	157
	158	<varlistentry>
	159	<term><option>--lines=</option></term>
	160	<term><option>-n</option></term>
	161
	162	<listitem><para>Controls the number of
	163	journal lines to show, counting from
	164	the most recent ones. Takes a positive
	165	integer argument. In follow mode
	166	defaults to 10, otherwise is unset
	167	thus not limiting how many lines are
	168	shown.</para></listitem>
	169	</varlistentry>
	170
	171	<varlistentry>
	172	<term><option>--no-tail</option></term>
	173
	174	<listitem><para>Show all stored output
	175	lines, even in follow mode. Undoes the
	176	effect of
	177	<option>--lines=</option>.</para></listitem>
	178	</varlistentry>
	179
	180	<varlistentry>
	181	<term><option>--output=</option></term>
	182	<term><option>-o</option></term>
	183
	184	<listitem><para>Controls the
f8813ec7 LP	185	formatting of the journal entries that
f8813ec7 LP	186	are shown. Takes one of
2af777ba LP	187	<literal>short</literal>,
	188	<literal>short-monotonic</literal>,
	189	<literal>verbose</literal>,
	190	<literal>export</literal>,
	191	<literal>json</literal>,
a6e87e90	192	<literal>json-pretty</literal>,
2af777ba LP	193	<literal>cat</literal>. <literal>short</literal>
	194	is the default and generates an output
	195	that is mostly identical to the
	196	formatting of classic syslog log
	197	files, showing one line per journal
	198	entry. <literal>short-monotonic</literal>
	199	is very similar but shows monotonic
	200	timestamps instead of wallclock
	201	timestamps. <literal>verbose</literal>
49f43d5f	202	shows the full structured entry items
2af777ba	203	with all
49f43d5f	204	fields. <literal>export</literal>
2af777ba LP	205	serializes the journal into a binary
	206	(but mostly text-based) stream
	207	suitable for backups and network
f8813ec7 LP	208	transfer (see <ulink
	209	url="http://www.freedesktop.org/wiki/Software/systemd/export">Journal
	210	Export Format</ulink> for more
	211	information). <literal>json</literal>
2af777ba	212	formats entries as JSON data
a6e87e90 LP	213	structures, one per
	214	line. <literal>json-pretty</literal>
	215	also formats entries as JSON data
	216	structures, but formats them in
	217	multiple lines in order to make them
	218	more readable for
	219	humans. <literal>cat</literal>
2af777ba LP	220	generates a very terse output only
	221	showing the actual message of each
	222	journal entry with no meta data, not
	223	even a timestamp.</para></listitem>
	224	</varlistentry>
	225
	226	<varlistentry>
	227	<term><option>--quiet</option></term>
	228	<term><option>-q</option></term>
	229
	230	<listitem><para>Suppresses any warning
49f43d5f	231	message regarding inaccessible system
2af777ba LP	232	journals when run as normal
	233	user.</para></listitem>
	234	</varlistentry>
	235
2bd3c38a	236	<varlistentry>
9e8a535f LP	237	<term><option>--merge</option></term>
9e8a535f LP	238	<term><option>-m</option></term>
2bd3c38a	239
9e8a535f LP	240	<listitem><para>Show entries
	241	interleaved from all available
	242	journals, including remote
	243	ones.</para></listitem>
2bd3c38a LP	244	</varlistentry>
2bd3c38a LP	245
59cea26a LP	246	<varlistentry>
	247	<term><option>--this-boot</option></term>
	248	<term><option>-b</option></term>
	249
	250	<listitem><para>Show data only from
931974af	251	current boot.</para></listitem>
59cea26a LP	252	</varlistentry>
59cea26a LP	253
a963990f LP	254	<varlistentry>
	255	<term><option>--directory=</option></term>
	256	<term><option>-D</option></term>
	257
	258	<listitem><para>Takes an absolute
	259	directory path as argument. If
14a65d65	260	specified will operate on the
a963990f LP	261	specified journal directory instead of
	262	the default runtime and system journal
	263	paths.</para></listitem>
	264	</varlistentry>
	265
941e990d LP	266	<varlistentry>
	267	<term><option>-p</option></term>
	268	<term><option>--priority=</option></term>
	269
	270	<listitem><para>Filter output by
	271	message priorities or priority
	272	ranges. Takes either a single numeric
	273	or textual log level (i.e. between
	274	0/<literal>emerg</literal> and
	275	7/<literal>debug</literal>), or a
	276	range of numeric/text log levels in
	277	the form FROM..TO. The log levels are
	278	the usual syslog log levels as
	279	documented in
	280	<citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
	281	i.e. <literal>emerg</literal> (0),
	282	<literal>alert</literal> (1),
	283	<literal>crit</literal> (2),
	284	<literal>err</literal> (3),
	285	<literal>warning</literal> (4),
	286	<literal>notice</literal> (5),
	287	<literal>info</literal> (6),
	288	<literal>debug</literal> (7). If a
	289	single log level is specified all
	290	messages with this log levels or a
	291	lower (hence more important) log level
	292	are shown. If a range is specified all
	293	messages within the range are shown,
	294	including both the start and the end
	295	value of the range.</para></listitem>
	296	</varlistentry>
	297
31094aae LP	298	<varlistentry>
	299	<term><option>--new-id128</option></term>
	300
	301	<listitem><para>Instead of showing
	302	journal contents generate a new 128
	303	bit ID suitable for identifying
	304	messages. This is intended for usage
	305	by developers who need a new
	306	identifier for a new message they
	307	introduce and want to make
	308	recognizable. Will print the new ID in
	309	three different formats which can be
	310	copied into source code or
	311	similar.</para></listitem>
	312	</varlistentry>
	313
	314	<varlistentry>
	315	<term><option>--header</option></term>
	316
	317	<listitem><para>Instead of showing
	318	journal contents show internal header
	319	information of the journal fiels
	320	accessed.</para></listitem>
a1a03e30 LP	321	</varlistentry>
	322
	323	<varlistentry>
	324	<term><option>--disk-usage</option></term>
	325
	326	<listitem><para>Shows the current disk
	327	usage of all
	328	journal files.</para></listitem>
31094aae LP	329	</varlistentry>
	330
	331	<varlistentry>
	332	<term><option>--setup-keys</option></term>
	333
	334	<listitem><para>Instead of showing
	335	journal contents generate a new key
	336	pair for Forward Secure Sealing
	337	(FSS). This will generate a sealing
	338	key and a verification key. The
	339	sealing key is stored in the journal
	340	data directory and shall remain on the
	341	host. The verification key should be
	342	stored externally.</para></listitem>
	343	</varlistentry>
	344
	345	<varlistentry>
	346	<term><option>--interval=</option></term>
	347
	348	<listitem><para>Specifies the change
	349	interval for the sealing key, when
	350	generating an FSS key pair with
	351	<option>--setup-keys</option>. Shorter
	352	intervals increase CPU consumption but
	353	shorten the time range of
	354	undetectable journal
	355	alterations. Defaults to
	356	15min.</para></listitem>
	357	</varlistentry>
	358
	359	<varlistentry>
	360	<term><option>--verify</option></term>
	361
	362	<listitem><para>Check the journal file
	363	for internal consistency. If the
	364	file has been generated with FSS
	365	enabled, and the FSS verification key
	366	has been specified with
	367	<option>--verify-key=</option>
	368	authenticity of the journal file is
	369	verified.</para></listitem>
	370	</varlistentry>
	371
	372	<varlistentry>
	373	<term><option>--verify-key=</option></term>
	374
	375	<listitem><para>Specifies the FSS
	376	verification key to use for the
	377	<option>--verify</option>
	378	operation.</para></listitem>
	379	</varlistentry>
	380
2af777ba LP	381	</variablelist>
	382	</refsect1>
	383
	384	<refsect1>
	385	<title>Exit status</title>
	386
	387	<para>On success 0 is returned, a non-zero failure
	388	code otherwise.</para>
	389	</refsect1>
	390
	391	<refsect1>
	392	<title>Environment</title>
	393
	394	<variablelist>
	395	<varlistentry>
	396	<term><varname>$SYSTEMD_PAGER</varname></term>
	397	<listitem><para>Pager to use when
	398	<option>--no-pager</option> is not given;
	399	overrides <varname>$PAGER</varname>. Setting
	400	this to an empty string or the value
	401	<literal>cat</literal> is equivalent to passing
	402	<option>--no-pager</option>.</para></listitem>
	403	</varlistentry>
	404	</variablelist>
	405	</refsect1>
	406
cbdca852 LP	407	<refsect1>
	408	<title>Examples</title>
	409
	410	<para>Without arguments all collected logs are shown
	411	unfiltered:</para>
	412
	413	<programlisting>journalctl</programlisting>
	414
	415	<para>With one match specified all entries with a field matching the expression are shown:</para>
	416
	417	<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service</programlisting>
	418
	419	<para>If two different fields are matched only entries matching both expressions at the same time are shown:</para>
	420
	421	<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097</programlisting>
	422
	423	<para>If two matches refer to the same field all entries matching either expression are shown:</para>
	424
	425	<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _SYSTEMD_UNIT=dbus.service</programlisting>
	426
	427	<para>If the separator "<literal>+</literal>" is used
	428	two expression may be combined in a logical OR. The
	429	following will show all messages from the Avahi
	430	service process with the PID 28097 plus all messages
	431	from the D-Bus service (from any of its
	432	processes):</para>
	433
	434	<programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097 + _SYSTEMD_UNIT=dbus.service</programlisting>
	435
b6a34514 LP	436	<para>Show all logs generated by the D-Bus executable:</para>
	437
	438	<programlisting>journalctl /usr/bin/dbus-daemon</programlisting>
	439
	440	<para>Show all logs of the kernel device node <filename>/dev/sda</filename>:</para>
	441
	442	<programlisting>journalctl /dev/sda</programlisting>
	443
cbdca852 LP	444	</refsect1>
cbdca852 LP	445
2af777ba LP	446	<refsect1>
	447	<title>See Also</title>
	448	<para>
	449	<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
01cf0ca8	450	<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
2af777ba	451	<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
ffa16db0	452	<citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
18b754d3	453	<citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
2af777ba LP	454	</para>
	455	</refsect1>
	456
	457	</refentry>