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 restart 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">promote</arg>
82 <arg>-D <replaceable>datadir</replaceable></arg>
86 <command>pg_ctl</command>
87 <arg choice="plain">reload</arg>
89 <arg>-D <replaceable>datadir</replaceable></arg>
93 <command>pg_ctl</command>
94 <arg choice="plain">status</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>
120 <arg>-o <replaceable>options</replaceable></arg>
124 <command>pg_ctl</command>
125 <arg choice="plain">unregister</arg>
126 <arg>-N <replaceable>servicename</replaceable></arg>
131 <refsect1 id="app-pg-ctl-description">
132 <title>Description</title>
134 <application>pg_ctl</application> is a utility for initializing a
135 <productname>PostgreSQL</productname> database cluster, starting,
136 stopping, or restarting the <productname>PostgreSQL</productname>
137 database server (<xref linkend="app-postgres">), or displaying the
138 status of a running server. Although the server can be started
139 manually, <application>pg_ctl</application> encapsulates tasks such
140 as redirecting log output and properly detaching from the terminal
141 and process group. It also provides convenient options for
146 The <option>init</option> or <option>initdb</option> mode creates a new
147 <productname>PostgreSQL</productname> database cluster. A database
148 cluster is a collection of databases that are managed by a single
149 server instance. This mode invokes the <command>initdb</command>
150 command. See <xref linkend="app-initdb"> for details.
154 In <option>start</option> mode, a new server is launched. The
155 server is started in the background, and its standard input is attached
156 to <filename>/dev/null</filename> (or <literal>nul</> on Windows).
157 On Unix-like systems, by default, the server's standard output and
158 standard error are sent to <application>pg_ctl</application>'s
159 standard output (not standard error). The standard output of
160 <application>pg_ctl</application> should then be redirected to a
161 file or piped to another process such as a log rotating program
162 like <application>rotatelogs</>; otherwise <command>postgres</command>
163 will write its output to the controlling terminal (from the
164 background) and will not leave the shell's process group. On
165 Windows, by default the server's standard output and standard error
166 are sent to the terminal. These default behaviors can be changed
167 by using <option>-l</option> to append the server's output to a log file.
168 Use of either <option>-l</option> or output redirection is recommended.
172 In <option>stop</option> mode, the server that is running in
173 the specified data directory is shut down. Three different
174 shutdown methods can be selected with the <option>-m</option>
175 option. <quote>Smart</quote> mode (the default) waits for all active
176 clients to disconnect and any online backup to finish.
177 If the server is in hot standby, recovery and streaming replication
178 will be terminated once all clients have disconnected.
179 <quote>Fast</quote> mode does not wait for clients to disconnect and
180 will terminate an online backup in progress. All active transactions are
181 rolled back and clients are forcibly disconnected, then the
182 server is shut down. <quote>Immediate</quote> mode will abort
183 all server processes immediately, without a clean shutdown.
184 This will lead to a crash-recovery run on the next restart.
188 <option>restart</option> mode effectively executes a stop followed
189 by a start. This allows changing the <command>postgres</command>
190 command-line options.
194 In <option>promote</option> mode, the standby server that is
195 running in the specified data directory is commanded to exit
196 recovery and begin read-write operations.
200 <option>reload</option> mode simply sends the
201 <command>postgres</command> process a <systemitem>SIGHUP</>
202 signal, causing it to reread its configuration files
203 (<filename>postgresql.conf</filename>,
204 <filename>pg_hba.conf</filename>, etc.). This allows changing of
205 configuration-file options that do not require a complete restart
210 <option>status</option> mode checks whether a server is running in
211 the specified data directory. If it is, the <acronym>PID</acronym>
212 and the command line options that were used to invoke it are
217 <option>kill</option> mode allows you to send a signal to a specified
218 process. This is particularly valuable for <productname>Microsoft Windows</>
219 which does not have a <application>kill</> command. Use
220 <literal>--help</> to see a list of supported signal names.
224 <option>register</option> mode allows you to register a system service
225 on <productname>Microsoft Windows</>. The <option>-S</option> option
226 allows selection of service start type, either <quote>auto</quote> (start
227 service automatically on system startup) or <quote>demand</quote> (start
232 <option>unregister</option> mode allows you to unregister a system service
233 on <productname>Microsoft Windows</>. This undoes the effects of the
234 <option>register</option> command.
238 <refsect1 id="app-pg-ctl-options">
239 <title>Options</title>
244 <term><option>-c</option></term>
247 Attempt to allow server crashes to produce core files, on platforms
248 where this is possible, by lifting any soft resource limit placed on
250 This is useful in debugging or diagnosing problems by allowing a
251 stack trace to be obtained from a failed server process.
257 <term><option>-D <replaceable class="parameter">datadir</replaceable></option></term>
260 Specifies the file system location of the database files. If
261 this is omitted, the environment variable
262 <envar>PGDATA</envar> is used.
268 <term><option>-l <replaceable class="parameter">filename</replaceable></option></term>
271 Append the server log output to
272 <replaceable>filename</replaceable>. If the file does not
273 exist, it is created. The <systemitem>umask</> is set to 077,
274 so access to the log file is disallowed to other users by default.
280 <term><option>-m <replaceable class="parameter">mode</replaceable></option></term>
283 Specifies the shutdown mode. <replaceable>mode</replaceable>
284 can be <literal>smart</literal>, <literal>fast</literal>, or
285 <literal>immediate</literal>, or the first letter of one of
286 these three. If this is omitted, <literal>smart</literal> is used.
292 <term><option>-o <replaceable class="parameter">options</replaceable></option></term>
295 Specifies options to be passed directly to the
296 <command>postgres</command> command.
299 The options should usually be surrounded by single or double
300 quotes to ensure that they are passed through as a group.
306 <term><option>-o <replaceable class="parameter">initdb-options</replaceable></option></term>
309 Specifies options to be passed directly to the
310 <command>initdb</command> command.
313 The options should usually be surrounded by single or double
314 quotes to ensure that they are passed through as a group.
320 <term><option>-p <replaceable class="parameter">path</replaceable></option></term>
323 Specifies the location of the <filename>postgres</filename>
324 executable. By default the <filename>postgres</filename> executable is taken from the same
325 directory as <command>pg_ctl</command>, or failing that, the hard-wired
326 installation directory. It is not necessary to use this
327 option unless you are doing something unusual and get errors
328 that the <filename>postgres</filename> executable was not found.
332 In <literal>init</literal> mode, this option analogously
333 specifies the location of the <filename>initdb</filename>
340 <term><option>-s</option></term>
343 Print only errors, no informational messages.
349 <term><option>-t</option></term>
352 The maximum number of seconds to wait when waiting for startup or
353 shutdown to complete. The default is 60 seconds.
359 <term><option>-w</option></term>
362 Wait for the startup or shutdown to complete.
363 Waiting is the default option for shutdowns, but not startups.
364 When waiting for startup, <command>pg_ctl</command> repeatedly
365 attempts to connect to the server.
366 When waiting for shutdown, <command>pg_ctl</command> waits for
367 the server to remove its <acronym>PID</acronym> file.
368 <command>pg_ctl</command> returns an exit code based on the
369 success of the startup or shutdown.
375 <term><option>-W</option></term>
378 Do not wait for startup or shutdown to complete. This is the
379 default for start and restart modes.
385 <refsect2 id="app-pg-ctl-windows-options">
386 <title>Options for Windows</title>
390 <term><option>-N <replaceable class="parameter">servicename</replaceable></option></term>
393 Name of the system service to register. The name will be used
394 as both the service name and the display name.
400 <term><option>-U <replaceable class="parameter">username</replaceable></option></term>
403 User name for the user to start the service. For domain users, use the
404 format <literal>DOMAIN\username</literal>.
410 <term><option>-P <replaceable class="parameter">password</replaceable></option></term>
413 Password for the user to start the service.
419 <term><option>-S <replaceable class="parameter">start-type</replaceable></option></term>
422 Start type of the system service to register. start-type can
423 be <literal>auto</literal>, or <literal>demand</literal>, or
424 the first letter of one of these two. If this is omitted,
425 <literal>auto</literal> is used.
436 <title>Environment</title>
440 <term><envar>PGDATA</envar></term>
444 Default data directory location.
452 <command>pg_ctl</command>, like most other <productname>PostgreSQL</>
454 also uses the environment variables supported by <application>libpq</>
455 (see <xref linkend="libpq-envars">).
456 For additional server variables, see <xref linkend="app-postgres">.
466 <term><filename>postmaster.pid</filename></term>
470 The existence of this file in the data directory is used to help
471 <application>pg_ctl</application> determine if the server is
478 <term><filename>postmaster.opts</filename></term>
481 <para>If this file exists in the data directory,
482 <application>pg_ctl</application> (in <option>restart</option> mode)
483 will pass the contents of the file as options to
484 <application>postgres</application>, unless overridden
485 by the <option>-o</option> option. The contents of this file
486 are also displayed in <option>status</option> mode.
495 <refsect1 id="R1-APP-PGCTL-2">
496 <title>Examples</title>
498 <refsect2 id="R2-APP-PGCTL-3">
499 <title>Starting the Server</title>
504 <prompt>$</prompt> <userinput>pg_ctl start</userinput>
509 To start the server, waiting until the server is
510 accepting connections:
512 <prompt>$</prompt> <userinput>pg_ctl -w start</userinput>
517 To start the server using port 5433, and
518 running without <function>fsync</function>, use:
520 <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>$</prompt> <userinput>pg_ctl stop -m fast</userinput>
540 <refsect2 id="R2-APP-PGCTL-5">
541 <title>Restarting the Server</title>
544 Restarting the server is almost equivalent to stopping the
545 server and starting it again,
546 except that <command>pg_ctl</command> saves and reuses the command line options that
547 were passed to the previously running instance. To restart
548 the server in the simplest form, use:
550 <prompt>$</prompt> <userinput>pg_ctl restart</userinput>
555 To restart the server,
556 waiting for it to shut down and restart:
558 <prompt>$</prompt> <userinput>pg_ctl -w restart</userinput>
563 To restart using port 5433, disabling <function>fsync</> upon restart:
565 <prompt>$</prompt> <userinput>pg_ctl -o "-F -p 5433" restart</userinput>
570 <refsect2 id="R2-APP-PGCTL-6">
571 <title>Showing the Server Status</title>
574 Here is sample status output from
575 <application>pg_ctl</application>:
577 <prompt>$</prompt> <userinput>pg_ctl status</userinput>
579 pg_ctl: server is running (PID: 13718)
580 /usr/local/pgsql/bin/postgres "-D" "/usr/local/pgsql/data" "-p" "5433" "-B" "128"
583 This is the command line that would be invoked in restart mode.
590 <title>See Also</title>
592 <simplelist type="inline">
593 <member><xref linkend="app-initdb"></member>
594 <member><xref linkend="app-postgres"></member>