| <?xml version='1.0'?> <!--*-nxml-*--> |
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| Copyright 2012 Lennart Poettering |
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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</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, 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. Similarly, 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 of 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>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> |
| <title>Options</title> |
| |
| <para>The following options are understood:</para> |
| |
| <variablelist> |
| <varlistentry> |
| <term><option>-h</option></term> |
| <term><option>--help</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>-l</option></term> |
| <term><option>--full</option></term> |
| |
| <listitem><para>Show all (printable) fields in |
| full.</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.</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 on the |
| command line. Note that this option is |
| only supported for the |
| <citerefentry><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, |
| a positive integer, is optional, and |
| defaults to 10. </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 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-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> |
| <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="http://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 any warning |
| message regarding inaccessible system |
| journals when run as 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><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> |
| </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>-u</option></term> |
| <term><option>--unit=</option></term> |
| |
| <listitem><para>Show messages for the |
| specified systemd unit. This will add |
| a match for messages from the unit |
| (<literal>_SYSTEMD_UNIT=</literal>) |
| and 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><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>, |
| i.e. <literal>emerg</literal> (0), |
| <literal>alert</literal> (1), |
| <literal>crit</literal> (2), |
| <literal>err</literal> (3), |
| <literal>warning</literal> (4), |
| <literal>notice</literal> (5), |
| <literal>info</literal> (6), |
| <literal>debug</literal> (7). If a |
| single log level is specified, all |
| messages with this log level or a |
| lower (hence more important) log level |
| are shown. If a range is specified, all |
| messages within the range are shown, |
| including both the start and the end |
| value of the range. This will add |
| <literal>PRIORITY=</literal> matches |
| for the specified |
| priorities.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>-c</option></term> |
| <term><option>--cursor=</option></term> |
| |
| <listitem><para>Start showing entries |
| from the location in the journal |
| specified by the passed |
| cursor.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--after-cursor=</option></term> |
| |
| <listitem><para>Start showing entries from the |
| location in the journal |
| <emphasis>after</emphasis> the location |
| specified by the this cursor. |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--since=</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.</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>--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>-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 |
| 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 argument. If specified, journalctl |
| will operate on 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>). |
| </para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--new-id128</option></term> |
| |
| <listitem><para>Instead of showing |
| journal contents, generate a new 128 |
| bit ID suitable for identifying |
| messages. This is intended for usage |
| by developers who need a new |
| identifier for a new message they |
| introduce and want to make |
| recognizable. This will print the new ID in |
| three different formats which can be |
| copied into source code or |
| similar.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--header</option></term> |
| |
| <listitem><para>Instead of showing |
| journal contents, show internal header |
| information of the journal fields |
| accessed.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--disk-usage</option></term> |
| |
| <listitem><para>Shows the current disk |
| usage of all |
| journal files.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--list-catalog |
| <optional><replaceable>ID128...</replaceable></optional> |
| </option></term> |
| |
| <listitem><para>List the contents of |
| the message catalog, as table of |
| message IDs plus their short |
| description strings.</para> |
| |
| <para>If any |
| <replaceable>ID128</replaceable>s are |
| specified, only those entries are shown. |
| </para> |
| </listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--dump-catalog |
| <optional><replaceable>ID128...</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>ID128</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. Also see the |
| <option>Seal=</option> option in |
| <citerefentry><refentrytitle>journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| for details.</para></listitem> |
| </varlistentry> |
| |
| <varlistentry> |
| <term><option>--force</option></term> |
| |
| <listitem><para>When --setup-keys is passed and |
| Forward Secure Sealing has already been set up, |
| 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> |
| |
| </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 class='environment-variables'> |
| <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 expressions may be combined in a logical OR. The |
| following will show all messages from the Avahi |
| service process with the PID 28097 plus all messages |
| from the D-Bus service (from any of its |
| processes):</para> |
| |
| <programlisting>journalctl _SYSTEMD_UNIT=avahi-daemon.service _PID=28097 + _SYSTEMD_UNIT=dbus.service</programlisting> |
| |
| <para>Show all logs generated by the D-Bus executable:</para> |
| |
| <programlisting>journalctl /usr/bin/dbus-daemon</programlisting> |
| |
| <para>Show all logs of the kernel device node <filename noindex='true'>/dev/sda</filename>:</para> |
| |
| <programlisting>journalctl /dev/sda</programlisting> |
| |
| <para>Show all kernel logs from previous boot:</para> |
| |
| <programlisting>journalctl -k -b -1</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> |