<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>
+ users who are members of the <literal>systemd-journal</literal>
group get access to the system journal and the
journals of other users.</para>
+
+ <para>The output is paged through
+ <command>less</command> by default, and long lines are
+ "truncated" to screen width. The hidden part can be
+ viewed by using the left-arrow and right-arrow
+ keys. Paging can be disabled, see
+ <option>--no-pager</option> and section Environment
+ below.</para>
+
+ <para>When outputing to a tty, lines are colored
+ according to priority: lines of level ERROR and higher
+ are colored red, lines of level NOTICE and higher are
+ highlighted, and other lines are displayed normally.
+ </para>
</refsect1>
<refsect1>
</varlistentry>
<varlistentry>
- <term><option>-l</option></term>
+ <term><option>--no-full</option></term>
<term><option>--full</option></term>
+ <term><option>-l</option></term>
+
+ <listitem><para>Ellipsize fields when
+ they do not fit in available columns.
+ The default is to show full fields,
+ allowing them to wrap or be truncated
+ by the pager if one is used.</para>
- <listitem><para>Show all (printable) fields in
- full.</para></listitem>
+ <para>The old options
+ <option>-l</option>/<option>--full</option>
+ are not useful anymore, except to undo
+ <option>--no-full</option>.</para></listitem>
</varlistentry>
<varlistentry>
<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>json-sse</literal>,
- <literal>cat</literal>. <literal>short</literal>
- is the default and generates an output
- that is mostly identical to the
- formatting of classic syslog
- 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 (see <ulink
- url="http://www.freedesktop.org/wiki/Software/systemd/json">Journal
- JSON Format</ulink> for more
- information). <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>json-sse</literal>
- also formats entries as JSON data
- structures, but wraps them in a format
- suitable for <ulink
- url="https://developer.mozilla.org/en-US/docs/Server-sent_events/Using_server-sent_events">Server-Sent
- Events</ulink>. <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>
+ are shown. Takes one of the following options:
+ </para>
+ <variablelist>
+ <varlistentry>
+ <term>
+ <option>short</option>
+ </term>
+ <listitem>
+ <para>is the default
+ and generates an output
+ that is mostly identical
+ to the formatting of
+ classic syslog files,
+ showing one line per
+ journal entry.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>short-iso</option>
+ </term>
+ <listitem>
+ <para>is very similar,
+ but shows ISO 8601
+ wallclock timestamps.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>short-precise</option>
+ </term>
+ <listitem>
+ <para>is very similar,
+ but shows timestamps
+ with full microsecond
+ precision.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>short-monotonic</option>
+ </term>
+ <listitem>
+ <para>is very similar,
+ but shows monotonic
+ timestamps instead of
+ wallclock timestamps.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>verbose</option>
+ </term>
+ <listitem>
+ <para>shows the
+ full-structured entry
+ items with all fields.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>export</option>
+ </term>
+ <listitem>
+ <para>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).</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>json</option>
+ </term>
+ <listitem>
+ <para>formats entries
+ as JSON data structures,
+ one per line (see <ulink
+ url="http://www.freedesktop.org/wiki/Software/systemd/json">Journal
+ JSON Format</ulink> for
+ more information).</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>json-pretty</option>
+ </term>
+ <listitem>
+ <para>formats entries as
+ JSON data structures,
+ but formats them in
+ multiple lines in order
+ to make them more
+ readable for humans.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>json-sse</option>
+ </term>
+ <listitem>
+ <para>formats entries as
+ JSON data structures,
+ but wraps them in a
+ format suitable for <ulink
+ url="https://developer.mozilla.org/en-US/docs/Server-sent_events/Using_server-sent_events">Server-Sent
+ Events</ulink>.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>
+ <option>cat</option>
+ </term>
+ <listitem>
+ <para>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>
+ </variablelist>
+ </listitem>
</varlistentry>
<varlistentry>
context of an error or log event,
possible solutions, as well as
pointers to support forums, developer
- documentation and any other relevant
+ documentation, and any other relevant
manuals. Note that help texts are not
available for all messages, but only
for selected ones. For more
please refer to the <ulink
url="http://www.freedesktop.org/wiki/Software/systemd/catalog">Message
Catalog Developer
- Documentation</ulink>.</para></listitem>
+ Documentation</ulink>.</para>
+
+ <para>Note: when attaching
+ <command>journalctl</command> output
+ to bug reports, please do
+ <emphasis>not</emphasis> use
+ <option>-x</option>.</para>
+ </listitem>
</varlistentry>
<varlistentry>
</varlistentry>
<varlistentry>
- <term><option>-b</option></term>
- <term><option>--this-boot</option></term>
+ <term><option>-b <optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional></option></term>
+ <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 add a match for
+ <literal>_BOOT_ID=</literal>.</para>
+
+ <para>The argument may be empty, in which case
+ logs for the current boot will be shown.</para>
+
+ <para>If the boot ID is omitted, a positive
+ <replaceable>offset</replaceable> will look up
+ the boots starting from the beginning of the
+ journal, and a equal-or-less-than zero
+ <replaceable>offset</replaceable> will look up
+ boots starting from the end of the
+ journal. Thus, <constant>1</constant> means the
+ first boot found in the journal in the
+ chronological order, <constant>2</constant> the
+ second and so on; while <constant>-0</constant>
+ is the last boot, <constant>-1</constant> the
+ boot before that, and so 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 <option>--directory</option> was
+ specified to look at logs from a different
+ machine).</para>
+
+ <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 a 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><para>Show data only from
- current boot. This will add a match
- for <literal>_BOOT_ID=</literal> for
- the current boot ID of the
- kernel.</para></listitem>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>--list-boots</option></term>
+
+ <listitem><para>Show a tabular list of
+ boot numbers (relative to 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 kernel messages from
- current boot. This implies <option>-b</option>
- and adds the match <literal>_TRANSPORT=kernel</literal>.
+ <listitem><para>Show only kernel messages. This
+ implies <option>-b</option> and adds the match
+ <literal>_TRANSPORT=kernel</literal>.
</para></listitem>
</varlistentry>
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 this cursor.
+ </para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><option>--since=</option></term>
<term><option>--until=</option></term>
<programlisting>journalctl /dev/sda</programlisting>
+ <para>Show all kernel logs from previous boot:</para>
+
+ <programlisting>journalctl -k -b -1</programlisting>
+
</refsect1>
<refsect1>