2 doc/src/sgml/ref/pg_ctl-ref.sgml
3 PostgreSQL documentation
6 <refentry id="app-pg-ctl">
8 <refentrytitle><application>pg_ctl</application></refentrytitle>
9 <manvolnum>1</manvolnum>
10 <refmiscinfo>Application</refmiscinfo>
14 <refname>pg_ctl</refname>
15 <refpurpose>initialize, start, stop, or control a <productname>PostgreSQL</productname> server</refpurpose>
18 <indexterm zone="app-pg-ctl">
19 <primary>pg_ctl</primary>
24 <command>pg_ctl</command>
25 <arg choice="plain">init[db]</arg>
27 <arg>-D <replaceable>datadir</replaceable></arg>
28 <arg>-o <replaceable>initdb-options</replaceable></arg>
32 <command>pg_ctl</command>
33 <arg choice="plain">start</arg>
35 <arg>-t <replaceable>seconds</replaceable></arg>
37 <arg>-D <replaceable>datadir</replaceable></arg>
38 <arg>-l <replaceable>filename</replaceable></arg>
39 <arg>-o <replaceable>options</replaceable></arg>
40 <arg>-p <replaceable>path</replaceable></arg>
45 <command>pg_ctl</command>
46 <arg choice="plain">stop</arg>
48 <arg>-t <replaceable>seconds</replaceable></arg>
50 <arg>-D <replaceable>datadir</replaceable></arg>
52 <group choice="plain">
55 <arg>i[mmediate]</arg>
61 <command>pg_ctl</command>
62 <arg choice="plain">restart</arg>
64 <arg>-t <replaceable>seconds</replaceable></arg>
66 <arg>-D <replaceable>datadir</replaceable></arg>
69 <group choice="plain">
72 <arg>i[mmediate]</arg>
75 <arg>-o <replaceable>options</replaceable></arg>
79 <command>pg_ctl</command>
80 <arg choice="plain">reload</arg>
82 <arg>-D <replaceable>datadir</replaceable></arg>
86 <command>pg_ctl</command>
87 <arg choice="plain">status</arg>
88 <arg>-D <replaceable>datadir</replaceable></arg>
92 <command>pg_ctl</command>
93 <arg choice="plain">promote</arg>
95 <arg>-D <replaceable>datadir</replaceable></arg>
99 <command>pg_ctl</command>
100 <arg choice="plain">kill</arg>
101 <arg choice="plain"><replaceable>signal_name</replaceable></arg>
102 <arg choice="plain"><replaceable>process_id</replaceable></arg>
106 <command>pg_ctl</command>
107 <arg choice="plain">register</arg>
108 <arg>-N <replaceable>servicename</replaceable></arg>
109 <arg>-U <replaceable>username</replaceable></arg>
110 <arg>-P <replaceable>password</replaceable></arg>
111 <arg>-D <replaceable>datadir</replaceable></arg>
113 <group choice="plain">
119 <arg>-t <replaceable>seconds</replaceable></arg>
121 <arg>-o <replaceable>options</replaceable></arg>
125 <command>pg_ctl</command>
126 <arg choice="plain">unregister</arg>
127 <arg>-N <replaceable>servicename</replaceable></arg>
132 <refsect1 id="app-pg-ctl-description">
133 <title>Description</title>
135 <application>pg_ctl</application> is a utility for initializing a
136 <productname>PostgreSQL</productname> database cluster, starting,
137 stopping, or restarting the <productname>PostgreSQL</productname>
138 database server (<xref linkend="app-postgres">), or displaying the
139 status of a running server. Although the server can be started
140 manually, <application>pg_ctl</application> encapsulates tasks such
141 as redirecting log output and properly detaching from the terminal
142 and process group. It also provides convenient options for
147 The <option>init</option> or <option>initdb</option> mode creates a new
148 <productname>PostgreSQL</productname> database cluster. A database
149 cluster is a collection of databases that are managed by a single
150 server instance. This mode invokes the <command>initdb</command>
151 command. See <xref linkend="app-initdb"> for details.
155 In <option>start</option> mode, a new server is launched. The
156 server is started in the background, and its standard input is attached
157 to <filename>/dev/null</filename> (or <literal>nul</> on Windows).
158 On Unix-like systems, by default, the server's standard output and
159 standard error are sent to <application>pg_ctl</application>'s
160 standard output (not standard error). The standard output of
161 <application>pg_ctl</application> should then be redirected to a
162 file or piped to another process such as a log rotating program
163 like <application>rotatelogs</>; otherwise <command>postgres</command>
164 will write its output to the controlling terminal (from the
165 background) and will not leave the shell's process group. On
166 Windows, by default the server's standard output and standard error
167 are sent to the terminal. These default behaviors can be changed
168 by using <option>-l</option> to append the server's output to a log file.
169 Use of either <option>-l</option> or output redirection is recommended.
173 In <option>stop</option> mode, the server that is running in
174 the specified data directory is shut down. Three different
175 shutdown methods can be selected with the <option>-m</option>
176 option. <quote>Smart</quote> mode (the default) waits for all active
177 clients to disconnect and any online backup to finish.
178 If the server is in hot standby, recovery and streaming replication
179 will be terminated once all clients have disconnected.
180 <quote>Fast</quote> mode does not wait for clients to disconnect and
181 will terminate an online backup in progress. All active transactions are
182 rolled back and clients are forcibly disconnected, then the
183 server is shut down. <quote>Immediate</quote> mode will abort
184 all server processes immediately, without a clean shutdown.
185 This will lead to a crash-recovery run on the next restart.
189 <option>restart</option> mode effectively executes a stop followed
190 by a start. This allows changing the <command>postgres</command>
191 command-line options.
195 <option>reload</option> mode simply sends the
196 <command>postgres</command> process a <systemitem>SIGHUP</>
197 signal, causing it to reread its configuration files
198 (<filename>postgresql.conf</filename>,
199 <filename>pg_hba.conf</filename>, etc.). This allows changing of
200 configuration-file options that do not require a complete restart
205 <option>status</option> mode checks whether a server is running in
206 the specified data directory. If it is, the <acronym>PID</acronym>
207 and the command line options that were used to invoke it are
212 In <option>promote</option> mode, the standby server that is
213 running in the specified data directory is commanded to exit
214 recovery and begin read-write operations.
218 <option>kill</option> mode allows you to send a signal to a specified
219 process. This is particularly valuable for <productname>Microsoft Windows</>
220 which does not have a <application>kill</> command. Use
221 <literal>--help</> to see a list of supported signal names.
225 <option>register</option> mode allows you to register a system service
226 on <productname>Microsoft Windows</>. The <option>-S</option> option
227 allows selection of service start type, either <quote>auto</quote> (start
228 service automatically on system startup) or <quote>demand</quote> (start
233 <option>unregister</option> mode allows you to unregister a system service
234 on <productname>Microsoft Windows</>. This undoes the effects of the
235 <option>register</option> command.
239 <refsect1 id="app-pg-ctl-options">
240 <title>Options</title>
245 <term><option>-c</option></term>
248 Attempt to allow server crashes to produce core files, on platforms
249 where this is possible, by lifting any soft resource limit placed on
251 This is useful in debugging or diagnosing problems by allowing a
252 stack trace to be obtained from a failed server process.
258 <term><option>-D <replaceable class="parameter">datadir</replaceable></option></term>
261 Specifies the file system location of the database files. If
262 this is omitted, the environment variable
263 <envar>PGDATA</envar> is used.
269 <term><option>-l <replaceable class="parameter">filename</replaceable></option></term>
272 Append the server log output to
273 <replaceable>filename</replaceable>. If the file does not
274 exist, it is created. The <systemitem>umask</> is set to 077,
275 so access to the log file is disallowed to other users by default.
281 <term><option>-m <replaceable class="parameter">mode</replaceable></option></term>
284 Specifies the shutdown mode. <replaceable>mode</replaceable>
285 can be <literal>smart</literal>, <literal>fast</literal>, or
286 <literal>immediate</literal>, or the first letter of one of
287 these three. If this is omitted, <literal>smart</literal> is used.
293 <term><option>-o <replaceable class="parameter">options</replaceable></option></term>
296 Specifies options to be passed directly to the
297 <command>postgres</command> command.
300 The options should usually be surrounded by single or double
301 quotes to ensure that they are passed through as a group.
307 <term><option>-o <replaceable class="parameter">initdb-options</replaceable></option></term>
310 Specifies options to be passed directly to the
311 <command>initdb</command> command.
314 The options should usually be surrounded by single or double
315 quotes to ensure that they are passed through as a group.
321 <term><option>-p <replaceable class="parameter">path</replaceable></option></term>
324 Specifies the location of the <filename>postgres</filename>
325 executable. By default the <filename>postgres</filename> executable is taken from the same
326 directory as <command>pg_ctl</command>, or failing that, the hard-wired
327 installation directory. It is not necessary to use this
328 option unless you are doing something unusual and get errors
329 that the <filename>postgres</filename> executable was not found.
333 In <literal>init</literal> mode, this option analogously
334 specifies the location of the <filename>initdb</filename>
341 <term><option>-s</option></term>
344 Print only errors, no informational messages.
350 <term><option>-t</option></term>
353 The maximum number of seconds to wait when waiting for startup or
354 shutdown to complete. The default is 60 seconds.
360 <term><option>-w</option></term>
363 Wait for the startup or shutdown to complete.
364 Waiting is the default option for shutdowns, but not startups.
365 When waiting for startup, <command>pg_ctl</command> repeatedly
366 attempts to connect to the server.
367 When waiting for shutdown, <command>pg_ctl</command> waits for
368 the server to remove its <acronym>PID</acronym> file.
369 <command>pg_ctl</command> returns an exit code based on the
370 success of the startup or shutdown.
376 <term><option>-W</option></term>
379 Do not wait for startup or shutdown to complete. This is the
380 default for start and restart modes.
386 <refsect2 id="app-pg-ctl-windows-options">
387 <title>Options for Windows</title>
391 <term><option>-N <replaceable class="parameter">servicename</replaceable></option></term>
394 Name of the system service to register. The name will be used
395 as both the service name and the display name.
401 <term><option>-P <replaceable class="parameter">password</replaceable></option></term>
404 Password for the user to start the service.
410 <term><option>-S <replaceable class="parameter">start-type</replaceable></option></term>
413 Start type of the system service to register. start-type can
414 be <literal>auto</literal>, or <literal>demand</literal>, or
415 the first letter of one of these two. If this is omitted,
416 <literal>auto</literal> is used.
422 <term><option>-U <replaceable class="parameter">username</replaceable></option></term>
425 User name for the user to start the service. For domain users, use the
426 format <literal>DOMAIN\username</literal>.
437 <title>Environment</title>
441 <term><envar>PGDATA</envar></term>
445 Default data directory location.
453 <command>pg_ctl</command>, like most other <productname>PostgreSQL</>
455 also uses the environment variables supported by <application>libpq</>
456 (see <xref linkend="libpq-envars">).
457 For additional server variables, see <xref linkend="app-postgres">.
467 <term><filename>postmaster.pid</filename></term>
471 The existence of this file in the data directory is used to help
472 <application>pg_ctl</application> determine if the server is
479 <term><filename>postmaster.opts</filename></term>
482 <para>If this file exists in the data directory,
483 <application>pg_ctl</application> (in <option>restart</option> mode)
484 will pass the contents of the file as options to
485 <application>postgres</application>, unless overridden
486 by the <option>-o</option> option. The contents of this file
487 are also displayed in <option>status</option> mode.
496 <refsect1 id="R1-APP-PGCTL-2">
497 <title>Examples</title>
499 <refsect2 id="R2-APP-PGCTL-3">
500 <title>Starting the Server</title>
505 <prompt>$</prompt> <userinput>pg_ctl start</userinput>
510 To start the server, waiting until the server is
511 accepting connections:
513 <prompt>$</prompt> <userinput>pg_ctl -w start</userinput>
518 To start the server using port 5433, and
519 running without <function>fsync</function>, use:
521 <prompt>$</prompt> <userinput>pg_ctl -o "-F -p 5433" start</userinput>
525 <refsect2 id="R2-APP-PGCTL-4">
526 <title>Stopping the Server</title>
528 To stop the server, use:
530 <prompt>$</prompt> <userinput>pg_ctl stop</userinput>
532 The <option>-m</option> option allows control over
533 <emphasis>how</emphasis> the server shuts down:
535 <prompt>$</prompt> <userinput>pg_ctl stop -m fast</userinput>
539 <refsect2 id="R2-APP-PGCTL-5">
540 <title>Restarting the Server</title>
543 Restarting the server is almost equivalent to stopping the
544 server and starting it again,
545 except that <command>pg_ctl</command> saves and reuses the command line options that
546 were passed to the previously running instance. To restart
547 the server in the simplest form, use:
549 <prompt>$</prompt> <userinput>pg_ctl restart</userinput>
554 To restart the server,
555 waiting for it to shut down and restart:
557 <prompt>$</prompt> <userinput>pg_ctl -w restart</userinput>
562 To restart using port 5433, disabling <function>fsync</> upon restart:
564 <prompt>$</prompt> <userinput>pg_ctl -o "-F -p 5433" restart</userinput>
568 <refsect2 id="R2-APP-PGCTL-6">
569 <title>Showing the Server Status</title>
572 Here is sample status output from
573 <application>pg_ctl</application>:
575 <prompt>$</prompt> <userinput>pg_ctl status</userinput>
577 pg_ctl: server is running (PID: 13718)
578 /usr/local/pgsql/bin/postgres "-D" "/usr/local/pgsql/data" "-p" "5433" "-B" "128"
581 This is the command line that would be invoked in restart mode.
588 <title>See Also</title>
590 <simplelist type="inline">
591 <member><xref linkend="app-initdb"></member>
592 <member><xref linkend="app-postgres"></member>