<?xml version='1.0'?> <!--*-nxml-*-->

<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"

"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<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">MATCH</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 a match argument is passed the output is

filtered accordingly. A match is in the format

<literal>FIELD=VALUE</literal>,

e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>. See

<citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>7</manvolnum></citerefentry>

for a list of well-known fields.</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 continously 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>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 structered entry items

with all

fiels. <literal>export</literal>

serializes the journal into a binary

(but mostly text-based) stream

suitable for backups and network

transfer. <literal>json</literal>

formats entries as JSON data

structures. <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 inaccessable system

journals when run as normal

user.</para></listitem>

</varlistentry>

<varlistentry>

<term><option>--local</option></term>

<term><option>-l</option></term>

<listitem><para>Show only locally

generated messages.</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 opearte on the

specified journal directory instead of

the default runtime and system journal

paths.</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>

</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>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>