man/journalctl.xml

   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
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   6   This file is part of systemd.
   7
   8   Copyright 2012 Lennart Poettering
   9
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  11   under the terms of the GNU General Public License as published by
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  23
  24 <refentry id="journalctl">
  25
  26         <refentryinfo>
  27                 <title>journalctl</title>
  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>
  41                 <refentrytitle>journalctl</refentrytitle>
  42                 <manvolnum>1</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>journalctl</refname>
  47                 <refname>systemd-journalctl</refname>
  48                 <refpurpose>Query the systemd journal</refpurpose>
  49         </refnamediv>
  50
  51         <refsynopsisdiv>
  52                 <cmdsynopsis>
  53                         <command>journalctl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt">MATCH</arg></command>
  54                 </cmdsynopsis>
  55         </refsynopsisdiv>
  56
  57         <refsect1>
  58                 <title>Description</title>
  59
  60                 <para><command>journalctl</command> may be
  61                 used to query the contents of the
  62                 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  63                 journal.</para>
  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
  69                 <para>If a match argument is passed the output is
  70                 filtered accordingly. A match is in the format
  71                 <literal>FIELD=VALUE</literal>,
  72                 e.g. <literal>_SYSTEMD_UNIT=httpd.service</literal>.</para>
  73
  74                 <para>Output is interleaved from all accessible
  75                 journal files, whether they are rotated or currently
  76                 being written, and regardless whether they belong to the
  77                 system itself or are accessible user journals.</para>
  78
  79                 <para>All users are granted access to their private
  80                 per-user journals. However, by default only root and
  81                 users who are members of the <literal>adm</literal>
  82                 group get access to the system journal and the
  83                 journals of other users.</para>
  84         </refsect1>
  85
  86         <refsect1>
  87                 <title>Options</title>
  88
  89                 <para>The following options are understood:</para>
  90
  91                 <variablelist>
  92                         <varlistentry>
  93                                 <term><option>--help</option></term>
  94                                 <term><option>-h</option></term>
  95
  96                                 <listitem><para>Prints a short help
  97                                 text and exits.</para></listitem>
  98                         </varlistentry>
  99
 100                         <varlistentry>
 101                                 <term><option>--version</option></term>
 102
 103                                 <listitem><para>Prints a short version
 104                                 string and exits.</para></listitem>
 105                         </varlistentry>
 106
 107                         <varlistentry>
 108                                 <term><option>--no-pager</option></term>
 109
 110                                 <listitem><para>Do not pipe output into a
 111                                 pager.</para></listitem>
 112                         </varlistentry>
 113
 114                         <varlistentry>
 115                                 <term><option>--all</option></term>
 116                                 <term><option>-a</option></term>
 117
 118                                 <listitem><para>Show all fields in
 119                                 full, even if they include unprintable
 120                                 characters or are very
 121                                 long.</para></listitem>
 122                         </varlistentry>
 123
 124                         <varlistentry>
 125                                 <term><option>--follow</option></term>
 126                                 <term><option>-f</option></term>
 127
 128                                 <listitem><para>Show only most recent
 129                                 journal entries, and continously print
 130                                 new entries as they are appended to
 131                                 the journal.</para></listitem>
 132                         </varlistentry>
 133
 134                         <varlistentry>
 135                                 <term><option>--lines=</option></term>
 136                                 <term><option>-n</option></term>
 137
 138                                 <listitem><para>Controls the number of
 139                                 journal lines to show, counting from
 140                                 the most recent ones. Takes a positive
 141                                 integer argument. In follow mode
 142                                 defaults to 10, otherwise is unset
 143                                 thus not limiting how many lines are
 144                                 shown.</para></listitem>
 145                         </varlistentry>
 146
 147                         <varlistentry>
 148                                 <term><option>--no-tail</option></term>
 149
 150                                 <listitem><para>Show all stored output
 151                                 lines, even in follow mode. Undoes the
 152                                 effect of
 153                                 <option>--lines=</option>.</para></listitem>
 154                         </varlistentry>
 155
 156                         <varlistentry>
 157                                 <term><option>--output=</option></term>
 158                                 <term><option>-o</option></term>
 159
 160                                 <listitem><para>Controls the
 161                                 formatting of the journal entries that are
 162                                 shown. Takes one of
 163                                 <literal>short</literal>,
 164                                 <literal>short-monotonic</literal>,
 165                                 <literal>verbose</literal>,
 166                                 <literal>export</literal>,
 167                                 <literal>json</literal>,
 168                                 <literal>cat</literal>. <literal>short</literal>
 169                                 is the default and generates an output
 170                                 that is mostly identical to the
 171                                 formatting of classic syslog log
 172                                 files, showing one line per journal
 173                                 entry. <literal>short-monotonic</literal>
 174                                 is very similar but shows monotonic
 175                                 timestamps instead of wallclock
 176                                 timestamps. <literal>verbose</literal>
 177                                 shows the full structered entry items
 178                                 with all
 179                                 fiels. <literal>export</literal>
 180                                 serializes the journal into a binary
 181                                 (but mostly text-based) stream
 182                                 suitable for backups and network
 183                                 transfer. <literal>json</literal>
 184                                 formats entries as JSON data
 185                                 structures. <literal>cat</literal>
 186                                 generates a very terse output only
 187                                 showing the actual message of each
 188                                 journal entry with no meta data, not
 189                                 even a timestamp.</para></listitem>
 190                         </varlistentry>
 191
 192                         <varlistentry>
 193                                 <term><option>--quiet</option></term>
 194                                 <term><option>-q</option></term>
 195
 196                                 <listitem><para>Suppresses any warning
 197                                 message regarding inaccessable system
 198                                 journals when run as normal
 199                                 user.</para></listitem>
 200                         </varlistentry>
 201
 202                         <varlistentry>
 203                                 <term><option>--local</option></term>
 204                                 <term><option>-l</option></term>
 205
 206                                 <listitem><para>Show only locally
 207                                 generated messages.</para></listitem>
 208                         </varlistentry>
 209
 210                         <varlistentry>
 211                                 <term><option>--new-id128</option></term>
 212
 213                                 <listitem><para>Instead of showing
 214                                 journal contents generate a new 128
 215                                 bit ID suitable for identifying
 216                                 messages. This is intended for usage
 217                                 by developers who need a new
 218                                 identifier for a new message they
 219                                 introduce and want to make
 220                                 recognizable. Will print the new ID in
 221                                 three different formats which can be
 222                                 copied into source code or
 223                                 similar.</para></listitem>
 224                         </varlistentry>
 225
 226                 </variablelist>
 227         </refsect1>
 228
 229         <refsect1>
 230                 <title>Exit status</title>
 231
 232                 <para>On success 0 is returned, a non-zero failure
 233                 code otherwise.</para>
 234         </refsect1>
 235
 236         <refsect1>
 237                 <title>Environment</title>
 238
 239                 <variablelist>
 240                         <varlistentry>
 241                                 <term><varname>$SYSTEMD_PAGER</varname></term>
 242                                 <listitem><para>Pager to use when
 243                                 <option>--no-pager</option> is not given;
 244                                 overrides <varname>$PAGER</varname>.  Setting
 245                                 this to an empty string or the value
 246                                 <literal>cat</literal> is equivalent to passing
 247                                 <option>--no-pager</option>.</para></listitem>
 248                         </varlistentry>
 249                 </variablelist>
 250         </refsect1>
 251
 252         <refsect1>
 253                 <title>See Also</title>
 254                 <para>
 255                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 256                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 257                         <citerefentry><refentrytitle>systemd-journald.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 258                 </para>
 259         </refsect1>
 260
 261 </refentry>