| <?xml version='1.0'?> <!--*-nxml-*--> |
| <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" |
| "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> |
| <!-- SPDX-License-Identifier: LGPL-2.1+ --> |
| |
| <refentry id="journalctl" |
| xmlns:xi="http://www.w3.org/2001/XInclude"> |
| |
| <refentryinfo> |
| <title>journalctl</title> |
| <productname>systemd</productname> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle>journalctl</refentrytitle> |
| <manvolnum>1</manvolnum> |
| </refmeta> |
| |
| <refnamediv> |
| <refname>journalctl</refname> |
| <refpurpose>Query the systemd journal</refpurpose> |
| </refnamediv> |
| |
| <refsynopsisdiv> |
| <cmdsynopsis> |
| <command>journalctl</command> |
| <arg choice="opt" rep="repeat">OPTIONS</arg> |
| <arg choice="opt" rep="repeat">MATCHES</arg> |
| </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 parameters, it 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, the character <literal>+</literal> may appear |
| as a separate word between other terms on the command line. This |
| causes all matches before and after to be combined in a |
| disjunction (i.e. logical OR).</para> |
| |
| <para>It is also possible to filter the entries by specifying an |
| absolute file path as an argument. The file path may be a file or |
| a symbolic link and the file must exist at the time of the query. If a |
| file path refers to an executable binary, an <literal>_EXE=</literal> |
| match for the canonicalized binary path is added to the query. If a |
| file path refers to an executable script, a <literal>_COMM=</literal> |
| match for the script name is added to the query. If a file path |
| refers to a device node, <literal>_KERNEL_DEVICE=</literal> matches for |
| the kernel name of the device and for each of its ancestor devices is |
| added to the query. Symbolic links are dereferenced, kernel names are |
| synthesized, and parent devices are identified from the environment at |
| the time of the query. In general, a device node is the best proxy for |
| an actual device, as log entries do not usually contain fields that |
| identify an actual device. For the resulting log entries to be correct |
| for the actual device, the relevant parts of the environment at the time |
| the entry was logged, in particular the actual device corresponding to |
| the device node, must have been the same as those at the time of the |
| query. Because device nodes generally change their corresponding devices |
| across reboots, specifying a device node path causes the resulting |
| entries to be restricted to those from the current boot.</para> |
| |
| <para>Additional constraints may be added using options |
| <option>--boot</option>, <option>--unit=</option>, etc., to |
| further limit what entries will be shown (logical AND).</para> |
| |
| <para>Output is interleaved from all accessible journal files, |
| whether they are rotated or currently being written, and |
| regardless of whether they belong to the system itself or are |
| accessible user journals.</para> |
| |
| <para>The set of journal files which will be used can be |
| modified using the <option>--user</option>, |
| <option>--system</option>, <option>--directory</option>, and |
| <option>--file</option> options, see below.</para> |
| |
| <para>All users are granted access to their private per-user |
| journals. However, by default, only root and users who are |
| members of a few special groups are granted access to the system |
| journal and the journals of other users. Members of the groups |
| <literal>systemd-journal</literal>, <literal>adm</literal>, and |
| <literal>wheel</literal> can read all journal files. Note |
| that the two latter groups traditionally have additional |
| privileges specified by the distribution. Members of the |
| <literal>wheel</literal> group can often perform administrative |
| tasks.</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 the |
| <option>--no-pager</option> option and the "Environment" section |
| below.</para> |
| |
| <para>When outputting 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; lines of level DEBUG |
| are colored lighter grey; other lines are displayed normally.</para> |
| </refsect1> |
| |
| <refsect1> |
| <title>Options</title> |
| |
| <para>The following options are understood:</para> |
| |
| <variablelist> |
| <varlistentry> |
| <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> |
| |
| <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> |
| <term><option>-a</option></term> |
| <term><option>--all</option></term> |
| |
| <listitem><para>Show all fields in full, even if they include unprintable characters or are very long. By |
| default, fields with unprintable characters are abbreviated as "blob data". (Note that the pager may escape |
| unprintable characters again.)</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-f</option></term> |
| <term><option>--follow</option></term> |
| |
| <listitem><para>Show only the most recent journal entries, |
| and continuously print new entries as they are appended to |
| the journal.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-e</option></term> |
| <term><option>--pager-end</option></term> |
| |
| <listitem><para>Immediately jump to the end of the journal |
| inside the implied pager tool. This implies |
| <option>-n1000</option> to guarantee that the pager will not |
| buffer logs of unbounded size. This may be overridden with |
| an explicit <option>-n</option> with some other numeric |
| value, while <option>-nall</option> will disable this cap. |
| Note that this option is only supported for the |
| <citerefentry project='man-pages'><refentrytitle>less</refentrytitle><manvolnum>1</manvolnum></citerefentry> |
| pager.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-n</option></term> |
| <term><option>--lines=</option></term> |
| |
| <listitem><para>Show the most recent journal events and |
| limit the number of events shown. If |
| <option>--follow</option> is used, this option is |
| implied. The argument is a positive integer or |
| <literal>all</literal> to disable line limiting. The default |
| value is 10 if no argument is given.</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>-r</option></term> |
| <term><option>--reverse</option></term> |
| |
| <listitem><para>Reverse output so that the newest entries |
| are displayed first.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-o</option></term> |
| <term><option>--output=</option></term> |
| |
| <listitem><para>Controls the formatting of the journal |
| entries that 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-full</option> |
| </term> |
| <listitem> |
| <para>is very similar, but shows timestamps in the format the <option>--since=</option> and |
| <option>--until=</option> options accept. Unlike the timestamp information shown in |
| <option>short</option> output mode this mode includes weekday, year and timezone information in the |
| output, and is locale-independent.</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-iso-precise</option> |
| </term> |
| <listitem> |
| <para>as for <option>short-iso</option> but includes full |
| microsecond precision.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> |
| <option>short-precise</option> |
| </term> |
| <listitem> |
| <para>is very similar, but shows classic syslog 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>short-unix</option> |
| </term> |
| <listitem> |
| <para>is very similar, but shows seconds passed since January 1st 1970 UTC instead of wallclock |
| timestamps ("UNIX time"). The time is shown with microsecond accuracy.</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="https://www.freedesktop.org/wiki/Software/systemd/export">Journal Export Format</ulink> |
| for more information). To import the binary stream back |
| into native journald format use |
| <citerefentry><refentrytitle>systemd-journal-remote</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> |
| <option>json</option> |
| </term> |
| <listitem> |
| <para>formats entries as JSON objects, separated by newline characters (see <ulink |
| url="https://www.freedesktop.org/wiki/Software/systemd/json">Journal JSON Format</ulink> for more |
| information). Field values are generally encoded as JSON strings, with three exceptions: |
| <orderedlist> |
| <listitem><para>Fields larger than 4096 bytes are encoded as <constant>null</constant> values. (This |
| may be turned off by passing <option>--all</option>, but be aware that this may allocate overly long |
| JSON objects.) </para></listitem> |
| |
| <listitem><para>Journal entries permit non-unique fields within the same log entry. JSON does not allow |
| non-unique fields within objects. Due to this, if a non-unique field is encountered a JSON array is |
| used as field value, listing all field values as elements.</para></listitem> |
| |
| <listitem><para>Fields containing non-printable or non-UTF8 bytes are encoded as arrays containing |
| the raw bytes individually formatted as unsigned numbers.</para></listitem> |
| </orderedlist> |
| |
| Note that this encoding is reversible (with the exception of the size limit).</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 by 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>json-seq</option> |
| </term> |
| <listitem> |
| <para>formats entries as JSON data structures, but prefixes them with an ASCII Record Separator |
| character (0x1E) and suffixes them with an ASCII Line Feed character (0x0A), in accordance with <ulink |
| url="https://tools.ietf.org/html/rfc7464">JavaScript Object Notation (JSON) Text Sequences </ulink> |
| (<literal>application/json-seq</literal>). |
| </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 metadata, |
| not even a timestamp.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term> |
| <option>with-unit</option> |
| </term> |
| <listitem> |
| <para>similar to short-full, but prefixes the unit and |
| user unit names instead of the traditional syslog |
| identifier. Useful when using templated instances, as it |
| will include the arguments in the unit names.</para> |
| </listitem> |
| </varlistentry> |
| </variablelist> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--output-fields=</option></term> |
| |
| <listitem><para>A comma separated list of the fields which should be included in the output. This only has an |
| effect for the output modes which would normally show all fields (<option>verbose</option>, |
| <option>export</option>, <option>json</option>, <option>json-pretty</option>, <option>json-sse</option> and |
| <option>json-seq</option>). The <literal>__CURSOR</literal>, <literal>__REALTIME_TIMESTAMP</literal>, |
| <literal>__MONOTONIC_TIMESTAMP</literal>, and <literal>_BOOT_ID</literal> fields are always |
| printed.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--utc</option></term> |
| |
| <listitem><para>Express time in Coordinated Universal Time |
| (UTC).</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--no-hostname</option></term> |
| |
| <listitem><para>Don't show the hostname field of log messages originating from the local host. This switch only |
| has an effect on the <option>short</option> family of output modes (see above).</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-x</option></term> |
| <term><option>--catalog</option></term> |
| |
| <listitem><para>Augment log lines with explanation texts from |
| the message catalog. This will add explanatory help texts to |
| log messages in the output where this is available. These |
| short help texts will explain the context of an error or log |
| event, possible solutions, as well as pointers to support |
| forums, developer documentation, and any other relevant |
| manuals. Note that help texts are not available for all |
| messages, but only for selected ones. For more information on |
| the message catalog, please refer to the |
| <ulink url="https://www.freedesktop.org/wiki/Software/systemd/catalog">Message Catalog Developer 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> |
| <term><option>-q</option></term> |
| <term><option>--quiet</option></term> |
| |
| <listitem><para>Suppresses all informational messages |
| (i.e. "-- Logs begin at …", "-- Reboot --"), |
| any warning messages regarding |
| inaccessible system journals when run as a normal |
| user.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-m</option></term> |
| <term><option>--merge</option></term> |
| |
| <listitem><para>Show entries interleaved from all available |
| journals, including remote ones.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-b <optional><optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional>|<constant>all</constant></optional></option></term> |
| <term><option>--boot<optional>=<optional><replaceable>ID</replaceable></optional><optional><replaceable>±offset</replaceable></optional>|<constant>all</constant></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 an |
| 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 chronological order, <constant>2</constant> the |
| second and so on; while <constant>-0</constant> is the last |
| boot, <constant>-1</constant> the boot before last, 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 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> |
| |
| <para>The special argument <constant>all</constant> can be |
| used to negate the effect of an earlier use of |
| <option>-b</option>.</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 |
| <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 |
| identifier |
| <replaceable>SYSLOG_IDENTIFIER</replaceable>.</para> |
| |
| <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>Â (0), |
| <literal>alert</literal>Â (1), <literal>crit</literal>Â (2), |
| <literal>err</literal>Â (3), <literal>warning</literal>Â (4), |
| <literal>notice</literal>Â (5), <literal>info</literal>Â (6), |
| <literal>debug</literal>Â (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>-g</option></term> |
| <term><option>--grep=</option></term> |
| |
| <listitem><para>Filter output to entries where the <varname>MESSAGE=</varname> |
| field matches the specified regular expression. PERL-compatible regular expressions |
| are used, see |
| <citerefentry><refentrytitle>pcre2pattern</refentrytitle><manvolnum>3</manvolnum></citerefentry> |
| for a detailed description of the syntax.</para> |
| |
| <para>If the pattern is all lowercase, matching is case insensitive. |
| Otherwise, matching is case sensitive. This can be overridden with the |
| <option>--case-sensitive</option> option, see below.</para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--case-sensitive<optional>=BOOLEAN</optional></option></term> |
| |
| <listitem><para>Make pattern matching case sensitive or case insenstive.</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>--cursor-file=<replaceable>FILE</replaceable></option></term> |
| |
| <listitem><para>If <replaceable>FILE</replaceable> exists and contains a |
| cursor, start showing entries <emphasis>after</emphasis> this location. |
| Otherwise the show entries according the other given options. At the end, |
| write the cursor of the last entry to <replaceable>FILE</replaceable>. Use |
| this option to continually read the journal by sequentially calling |
| <command>journalctl</command>.</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>--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 the oldest 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.</para> |
| |
| <para><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> |
| |
| <para>These three switches may also be combined with <option>--rotate</option> into one command. If so, all |
| active files are rotated first, and the requested vacuuming operation is executed right after. The rotation has |
| the effect that all currently active files are archived (and potentially new, empty journal files opened as |
| replacement), and hence the vacuuming operation has the greatest effect as it can take all log data written so |
| far into account.</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 (but see |
| <option>--relinquish-var</option> below), 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>--relinquish-var</option></term> |
| |
| <listitem><para>Asks the journal daemon for the reverse operation to <option>--flush</option>: if |
| requested the daemon will write further log data to <filename>/run/log/journal/</filename> and stops |
| writing to <filename>/var/log/journal/</filename>. A subsequent call to <option>--flush</option> |
| causes the log output to switch back to <filename>/var/log/journal/</filename>, see |
| above.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--smart-relinquish-var</option></term> |
| |
| <listitem><para>Similar to <option>--relinquish-var</option> but executes no operation if the root file |
| system and <filename>/var/lib/journal/</filename> reside on the same mount point. This operation is |
| used during system shutdown in order to make the journal daemon stop writing data to |
| <filename>/var/log/journal/</filename> in case that directory is located on a mount point that needs |
| to be unmounted.</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. Journal file rotation has the effect that all currently active journal files are marked |
| as archived and renamed, so that they are never written to in future. New (empty) journal files are then |
| created in their place. This operation may be combined with <option>--vacuum-size=</option>, |
| <option>--vacuum-time=</option> and <option>--vacuum-file=</option> into a single command, see |
| above.</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 |
| journalctl _SYSTEMD_CGROUP=/user.slice/user-42.slice/session-c1.scope</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>To show all fields emitted <emphasis>by</emphasis> a unit and <emphasis>about</emphasis> |
| the unit, option <option>-u</option>/<option>--unit=</option> should be used. |
| <command>journalctl -u <replaceable>name</replaceable></command> |
| expands to a complex filter similar to |
| <programlisting>_SYSTEMD_UNIT=<replaceable>name</replaceable>.service |
| + UNIT=<replaceable>name</replaceable>.service _PID=1 |
| + OBJECT_SYSTEMD_UNIT=<replaceable>name</replaceable>.service _UID=0 |
| + COREDUMP_UNIT=<replaceable>name</replaceable>.service _UID=0 MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1 |
| </programlisting> |
| (see <citerefentry><refentrytitle>systemd.journal-fields</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for an explanation of those patterns). |
| </para> |
| |
| <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>, |
| <citerefentry><refentrytitle>systemd-journal-remote.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, |
| <citerefentry><refentrytitle>systemd-journal-upload.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
| </para> |
| </refsect1> |
| </refentry> |