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+<chapter xmlns="http://docbook.org/ns/docbook"
+        xmlns:xlink="http://www.w3.org/1999/xlink"
+        xmlns:xi="http://www.w3.org/2001/XInclude"
+        version="5.0"
+        xml:id="sec-logging">
+
+<title>Logging</title>
+
+<para>System-wide logging is provided by systemd’s
+<emphasis>journal</emphasis>, which subsumes traditional logging
+daemons such as syslogd and klogd.  Log entries are kept in binary
+files in <filename>/var/log/journal/</filename>.  The command
+<literal>journalctl</literal> allows you to see the contents of the
+journal.  For example,
+
+<screen>
+$ journalctl -b
+</screen>
+
+shows all journal entries since the last reboot.  (The output of
+<command>journalctl</command> is piped into <command>less</command> by
+default.)  You can use various options and match operators to restrict
+output to messages of interest.  For instance, to get all messages
+from PostgreSQL:
+
+<screen>
+$ journalctl -u postgresql.service
+-- Logs begin at Mon, 2013-01-07 13:28:01 CET, end at Tue, 2013-01-08 01:09:57 CET. --
+...
+Jan 07 15:44:14 hagbard postgres[2681]: [2-1] LOG:  database system is shut down
+-- Reboot --
+Jan 07 15:45:10 hagbard postgres[2532]: [1-1] LOG:  database system was shut down at 2013-01-07 15:44:14 CET
+Jan 07 15:45:13 hagbard postgres[2500]: [1-1] LOG:  database system is ready to accept connections
+</screen>
+
+Or to get all messages since the last reboot that have at least a
+“critical” severity level:
+
+<screen>
+$ journalctl -b -p crit
+Dec 17 21:08:06 mandark sudo[3673]: pam_unix(sudo:auth): auth could not identify password for [alice]
+Dec 29 01:30:22 mandark kernel[6131]: [1053513.909444] CPU6: Core temperature above threshold, cpu clock throttled (total events = 1)
+</screen>
+
+</para>
+
+<para>The system journal is readable by root and by users in the
+<literal>wheel</literal> and <literal>systemd-journal</literal>
+groups.  All users have a private journal that can be read using
+<command>journalctl</command>.</para>
+
+</chapter>
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