doc/src/sgml/ref/pg_ctl-ref.sgml

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   2 $PostgreSQL$
   3 PostgreSQL documentation
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   5
   6 <refentry id="app-pg-ctl">
   7  <refmeta>
   8   <refentrytitle id="app-pg-ctl-title"><application>pg_ctl</application></refentrytitle>
   9   <manvolnum>1</manvolnum>
  10   <refmiscinfo>Application</refmiscinfo>
  11  </refmeta>
  12
  13  <refnamediv>
  14   <refname>pg_ctl</refname>
  15   <refpurpose>start, stop, or restart a <productname>PostgreSQL</productname> server</refpurpose>
  16  </refnamediv>
  17
  18  <indexterm zone="app-pg-ctl">
  19   <primary>pg_ctl</primary>
  20  </indexterm>
  21
  22  <refsynopsisdiv>
  23   <cmdsynopsis>
  24
  25    <command>pg_ctl</command>
  26    <arg choice="plain">start</arg>
  27    <arg>-w</arg>
  28    <arg>-t <replaceable>seconds</replaceable></arg>
  29    <arg>-s</arg>
  30    <arg>-D <replaceable>datadir</replaceable></arg>
  31    <arg>-l <replaceable>filename</replaceable></arg>
  32    <arg>-o <replaceable>options</replaceable></arg>
  33    <arg>-p <replaceable>path</replaceable></arg>
  34    <arg>-c</arg>
  35    <sbr>
  36
  37    <command>pg_ctl</command>
  38    <arg choice="plain">stop</arg>
  39    <arg>-W</arg>
  40    <arg>-t <replaceable>seconds</replaceable></arg>
  41    <arg>-s</arg>
  42    <arg>-D <replaceable>datadir</replaceable></arg>
  43    <arg>-m
  44      <group choice="plain">
  45        <arg>s[mart]</arg>
  46        <arg>f[ast]</arg>
  47        <arg>i[mmediate]</arg>
  48      </group>
  49    </arg>
  50    <sbr>
  51
  52    <command>pg_ctl</command>
  53    <arg choice="plain">restart</arg>
  54    <arg>-w</arg>
  55    <arg>-t <replaceable>seconds</replaceable></arg>
  56    <arg>-s</arg>
  57    <arg>-D <replaceable>datadir</replaceable></arg>
  58    <arg>-c</arg>
  59    <arg>-m
  60      <group choice="plain">
  61        <arg>s[mart]</arg>
  62        <arg>f[ast]</arg>
  63        <arg>i[mmediate]</arg>
  64      </group>
  65    </arg>
  66    <arg>-o <replaceable>options</replaceable></arg>
  67    <sbr>
  68
  69    <command>pg_ctl</command>
  70    <arg choice="plain">reload</arg>
  71    <arg>-s</arg>
  72    <arg>-D <replaceable>datadir</replaceable></arg>
  73    <sbr>
  74
  75    <command>pg_ctl</command>
  76    <arg choice="plain">status</arg>
  77    <arg>-D <replaceable>datadir</replaceable></arg>
  78    <sbr>
  79
  80    <command>pg_ctl</command>
  81    <arg choice="plain">kill</arg>
  82    <arg><replaceable>signal_name</replaceable></arg>
  83    <arg><replaceable>process_id</replaceable></arg>
  84    <sbr>
  85
  86    <command>pg_ctl</command>
  87    <arg choice="plain">register</arg>
  88    <arg>-N <replaceable>servicename</replaceable></arg>
  89    <arg>-U <replaceable>username</replaceable></arg>
  90    <arg>-P <replaceable>password</replaceable></arg>
  91    <arg>-D <replaceable>datadir</replaceable></arg>
  92    <arg>-w</arg>
  93    <arg>-t <replaceable>seconds</replaceable></arg>
  94    <arg>-o <replaceable>options</replaceable></arg>
  95    <sbr>
  96
  97    <command>pg_ctl</command>
  98    <arg choice="plain">unregister</arg>
  99    <arg>-N <replaceable>servicename</replaceable></arg>
 100
 101   </cmdsynopsis>
 102  </refsynopsisdiv>
 103
 104
 105  <refsect1 id="app-pg-ctl-description">
 106   <title>Description</title>
 107   <para>
 108    <application>pg_ctl</application> is a utility for starting,
 109    stopping, or restarting the <productname>PostgreSQL</productname>
 110    backend server (<xref linkend="app-postgres">), or displaying the
 111    status of a running server.  Although the server can be started
 112    manually, <application>pg_ctl</application> encapsulates tasks such
 113    as redirecting log output and properly detaching from the terminal
 114    and process group. It also provides convenient options for
 115    controlled shutdown.
 116   </para>
 117
 118   <para>
 119    In <option>start</option> mode, a new server is launched.  The
 120    server is started in the background, and standard input is attached to
 121    <filename>/dev/null</filename>.  The standard output and standard
 122    error are either appended to a log file (if the <option>-l</option>
 123    option is used), or redirected to <application>pg_ctl</application>'s
 124    standard output (not standard error).  If no log file is chosen, the
 125    standard output of <application>pg_ctl</application> should be redirected
 126    to a file or piped to another process such as a log rotating program
 127    like <application>rotatelogs</>; otherwise <command>postgres</command>
 128    will write its output to the controlling terminal (from the background)
 129    and will not leave the shell's process group.
 130   </para>
 131
 132   <para>
 133    In <option>stop</option> mode, the server that is running in
 134    the specified data directory is shut down.  Three different
 135    shutdown methods can be selected with the <option>-m</option>
 136    option: <quote>Smart</quote> mode waits for online backup mode
 137    to finish and all the clients to disconnect.  This is the default.
 138    <quote>Fast</quote> mode does not wait for clients to disconnect and
 139    will terminate an online backup in progress.  All active transactions are
 140    rolled back and clients are forcibly disconnected, then the
 141    server is shut down.  <quote>Immediate</quote> mode will abort
 142    all server processes without a clean shutdown.  This will lead to
 143    a recovery run on restart.
 144   </para>
 145
 146   <para>
 147    <option>restart</option> mode effectively executes a stop followed
 148    by a start.  This allows changing the <command>postgres</command>
 149    command-line options.
 150   </para>
 151
 152   <para>
 153    <option>reload</option> mode simply sends the
 154    <command>postgres</command> process a <systemitem>SIGHUP</>
 155    signal, causing it to reread its configuration files
 156    (<filename>postgresql.conf</filename>,
 157    <filename>pg_hba.conf</filename>, etc.).  This allows changing of
 158    configuration-file options that do not require a complete restart
 159    to take effect.
 160   </para>
 161
 162   <para>
 163    <option>status</option> mode checks whether a server is running in
 164    the specified data directory. If it is, the <acronym>PID</acronym>
 165    and the command line options that were used to invoke it are
 166    displayed.
 167   </para>
 168
 169   <para>
 170    <option>kill</option> mode allows you to send a signal to a specified
 171     process.  This is particularly valuable for <productname>Microsoft Windows</>
 172     which does not have a <application>kill</> command.  Use
 173     <literal>--help</> to see a list of supported signal names.
 174   </para>
 175
 176   <para>
 177    <option>register</option> mode allows you to register a system service
 178    on <productname>Microsoft Windows</>.
 179   </para>
 180
 181   <para>
 182    <option>unregister</option> mode allows you to unregister a system service
 183    on <productname>Microsoft Windows</>, previously registered with the
 184    <option>register</option> command.
 185   </para>
 186  </refsect1>
 187
 188  <refsect1 id="app-pg-ctl-options">
 189   <title>Options</title>
 190
 191     <variablelist>
 192
 193      <varlistentry>
 194       <term><option>-c</option></term>
 195       <listitem>
 196        <para>
 197         Attempt to allow server crashes to produce core files, on platforms
 198         where this available, by lifting any soft resource limit placed on
 199         them.
 200         This is useful in debugging or diagnosing problems by allowing a
 201         stack trace to be obtained from a failed server process.
 202        </para>
 203       </listitem>
 204      </varlistentry>
 205
 206      <varlistentry>
 207       <term><option>-D <replaceable class="parameter">datadir</replaceable></option></term>
 208       <listitem>
 209        <para>
 210         Specifies the file system location of the database files.  If
 211         this is omitted, the environment variable
 212         <envar>PGDATA</envar> is used.
 213        </para>
 214       </listitem>
 215      </varlistentry>
 216
 217      <varlistentry>
 218       <term><option>-l <replaceable class="parameter">filename</replaceable></option></term>
 219       <listitem>
 220        <para>
 221         Append the server log output to
 222         <replaceable>filename</replaceable>.  If the file does not
 223         exist, it is created.  The <systemitem>umask</> is set to 077, so access to
 224         the log file from other users is disallowed by default.
 225        </para>
 226       </listitem>
 227      </varlistentry>
 228
 229      <varlistentry>
 230       <term><option>-m <replaceable class="parameter">mode</replaceable></option></term>
 231       <listitem>
 232        <para>
 233         Specifies the shutdown mode.  <replaceable>mode</replaceable>
 234         can be <literal>smart</literal>, <literal>fast</literal>, or
 235         <literal>immediate</literal>, or the first letter of one of
 236         these three.
 237        </para>
 238       </listitem>
 239      </varlistentry>
 240
 241      <varlistentry>
 242       <term><option>-o <replaceable class="parameter">options</replaceable></option></term>
 243       <listitem>
 244        <para>
 245         Specifies options to be passed directly to the
 246         <command>postgres</command> command.
 247        </para>
 248        <para>
 249         The options are usually surrounded by single or double
 250         quotes to ensure that they are passed through as a group.
 251        </para>
 252       </listitem>
 253      </varlistentry>
 254
 255      <varlistentry>
 256       <term><option>-p <replaceable class="parameter">path</replaceable></option></term>
 257       <listitem>
 258        <para>
 259         Specifies the location of the <filename>postgres</filename>
 260         executable.  By default the <filename>postgres</filename> executable is taken from the same
 261         directory as <command>pg_ctl</command>, or failing that, the hard-wired
 262         installation directory.  It is not necessary to use this
 263         option unless you are doing something unusual and get errors
 264         that the <filename>postgres</filename> executable was not found.
 265        </para>
 266       </listitem>
 267      </varlistentry>
 268
 269      <varlistentry>
 270       <term><option>-s</option></term>
 271       <listitem>
 272        <para>
 273         Only print errors, no informational messages.
 274        </para>
 275       </listitem>
 276      </varlistentry>
 277
 278      <varlistentry>
 279       <term><option>-t</option></term>
 280       <listitem>
 281        <para>
 282         The number of seconds to wait when waiting for start or shutdown
 283         to complete.
 284        </para>
 285       </listitem>
 286      </varlistentry>
 287
 288      <varlistentry>
 289       <term><option>-w</option></term>
 290       <listitem>
 291        <para>
 292         Wait for the start or shutdown to complete.  The default wait time
 293         is 60 seconds.  This is the default option for shutdowns. A successful
 294         shutdown is indicated by removal of the <acronym>PID</acronym>
 295         file. For starting up, a successful <command>psql -l</command>
 296         indicates success. <command>pg_ctl</command> will attempt to
 297         use the proper port for <application>psql</>. If the environment variable
 298         <envar>PGPORT</envar> exists, that is used. Otherwise, it will see if a port
 299         has been set in the <filename>postgresql.conf</filename> file.
 300         If neither of those is used, it will use the default port that
 301         <productname>PostgreSQL</productname> was compiled with
 302         (5432 by default). When waiting, <command>pg_ctl</command> will
 303         return an accurate exit code based on the success of the startup
 304         or shutdown.
 305        </para>
 306       </listitem>
 307      </varlistentry>
 308
 309      <varlistentry>
 310       <term><option>-W</option></term>
 311       <listitem>
 312        <para>
 313         Do not wait for start or shutdown to complete.  This is the
 314         default for starts and restarts.
 315        </para>
 316       </listitem>
 317      </varlistentry>
 318    </variablelist>
 319
 320   <refsect2 id="app-pg-ctl-windows-options">
 321    <title>Options for Windows</title>
 322
 323    <variablelist>
 324     <varlistentry>
 325      <term><option>-N <replaceable class="parameter">servicename</replaceable></option></term>
 326      <listitem>
 327       <para>
 328        Name of the system service to register. The name will be used
 329        as both the service name and the display name.
 330       </para>
 331      </listitem>
 332     </varlistentry>
 333
 334     <varlistentry>
 335      <term><option>-P <replaceable class="parameter">password</replaceable></option></term>
 336      <listitem>
 337       <para>
 338        Password for the user to start the service.
 339       </para>
 340      </listitem>
 341     </varlistentry>
 342
 343     <varlistentry>
 344      <term><option>-U <replaceable class="parameter">username</replaceable></option></term>
 345      <listitem>
 346       <para>
 347        User name for the user to start the service. For domain users, use the
 348        format <literal>DOMAIN\username</literal>.
 349       </para>
 350      </listitem>
 351     </varlistentry>
 352    </variablelist>
 353   </refsect2>
 354
 355  </refsect1>
 356
 357
 358  <refsect1>
 359   <title>Environment</title>
 360
 361   <variablelist>
 362    <varlistentry>
 363     <term><envar>PGDATA</envar></term>
 364
 365     <listitem>
 366      <para>
 367       Default data directory location.
 368      </para>
 369     </listitem>
 370    </varlistentry>
 371
 372    <varlistentry>
 373     <term><envar>PGPORT</envar></term>
 374
 375     <listitem>
 376      <para>
 377       Default port for <xref linkend="app-psql"> (used by the -w option).
 378      </para>
 379     </listitem>
 380    </varlistentry>
 381   </variablelist>
 382
 383   <para>
 384    For additional server variables, see <xref linkend="app-postgres">.
 385    This utility, like most other <productname>PostgreSQL</> utilities,
 386    also uses the environment variables supported by <application>libpq</>
 387    (see <xref linkend="libpq-envars">).
 388   </para>
 389  </refsect1>
 390
 391
 392  <refsect1>
 393   <title>Files</title>
 394
 395   <variablelist>
 396    <varlistentry>
 397     <term><filename>postmaster.pid</filename></term>
 398
 399     <listitem>
 400      <para>
 401       The existence of this file in the data directory is used to help
 402       <application>pg_ctl</application> determine if the server is
 403       currently running or not.
 404      </para>
 405     </listitem>
 406    </varlistentry>
 407
 408    <varlistentry>
 409     <term><filename>postmaster.opts</filename></term>
 410
 411     <listitem>
 412      <para>If this file exists in the data directory,
 413       <application>pg_ctl</application> (in <option>restart</option> mode)
 414       will pass the contents of the file as options to
 415       <application>postgres</application>, unless overridden
 416       by the <option>-o</option> option. The contents of this file
 417       are also displayed in <option>status</option> mode.
 418      </para>
 419     </listitem>
 420    </varlistentry>
 421
 422    <varlistentry>
 423     <term><filename>postgresql.conf</filename></term>
 424
 425     <listitem>
 426      <para>
 427       This file, located in the data directory, is parsed to find the
 428       proper port to use with <application>psql</application> when the
 429       <option>-w</option> is given in <option>start</option> mode.
 430      </para>
 431     </listitem>
 432    </varlistentry>
 433
 434   </variablelist>
 435  </refsect1>
 436
 437
 438  <refsect1>
 439   <title>Notes</title>
 440
 441   <para>
 442    Waiting for complete start is not a well-defined operation and might
 443    fail if access control is set up so that a local client cannot
 444    connect without manual interaction (e.g., password authentication).  For
 445    additional connection variables, see <xref linkend="libpq-envars">,
 446    and for passwords, also see <xref linkend="libpq-pgpass">.
 447   </para>
 448  </refsect1>
 449
 450
 451  <refsect1 id="R1-APP-PGCTL-2">
 452   <title>Examples</title>
 453
 454   <refsect2 id="R2-APP-PGCTL-3">
 455    <title>Starting the Server</title>
 456
 457    <para>
 458     To start up a server:
 459 <screen>
 460 <prompt>$</prompt> <userinput>pg_ctl start</userinput>
 461 </screen>
 462    </para>
 463
 464    <para>
 465     An example of starting the server, blocking until the server has
 466     come up is:
 467 <screen>
 468 <prompt>$</prompt> <userinput>pg_ctl -w start</userinput>
 469 </screen>
 470    </para>
 471
 472    <para>
 473     For a server using port 5433, and
 474     running without <function>fsync</function>, use:
 475 <screen>
 476 <prompt>$</prompt> <userinput>pg_ctl -o "-F -p 5433" start</userinput>
 477 </screen>
 478    </para>
 479   </refsect2>
 480
 481   <refsect2 id="R2-APP-PGCTL-4">
 482    <title>Stopping the Server</title>
 483    <para>
 484 <screen>
 485 <prompt>$</prompt> <userinput>pg_ctl stop</userinput>
 486 </screen>
 487     stops the server. Using the <option>-m</option> switch allows one
 488     to control <emphasis>how</emphasis> the backend shuts down.
 489    </para>
 490   </refsect2>
 491
 492   <refsect2 id="R2-APP-PGCTL-5">
 493    <title>Restarting the Server</title>
 494
 495    <para>
 496     Restarting the server is almost equivalent to stopping the
 497     server and starting it again
 498     except that <command>pg_ctl</command> saves and reuses the command line options that
 499     were passed to the previously running instance.  To restart
 500     the server in the simplest form, use:
 501 <screen>
 502 <prompt>$</prompt> <userinput>pg_ctl restart</userinput>
 503 </screen>
 504    </para>
 505
 506    <para>
 507     To restart server,
 508     waiting for it to shut down and to come up:
 509 <screen>
 510 <prompt>$</prompt> <userinput>pg_ctl -w restart</userinput>
 511 </screen>
 512    </para>
 513
 514    <para>
 515     To restart using port 5433 and disabling <function>fsync</> after restarting:
 516 <screen>
 517 <prompt>$</prompt> <userinput>pg_ctl -o "-F -p 5433" restart</userinput>
 518 </screen>
 519    </para>
 520   </refsect2>
 521
 522   <refsect2 id="R2-APP-PGCTL-6">
 523    <title>Showing the Server Status</title>
 524
 525    <para>
 526     Here is a sample status output from
 527     <application>pg_ctl</application>:
 528 <screen>
 529 <prompt>$</prompt> <userinput>pg_ctl status</userinput>
 530 <computeroutput>
 531 pg_ctl: server is running (pid: 13718)
 532 Command line was:
 533 /usr/local/pgsql/bin/postgres '-D' '/usr/local/pgsql/data' '-p' '5433' '-B' '128'
 534 </computeroutput>
 535 </screen>
 536     This is the command line that would be invoked in restart mode.
 537    </para>
 538   </refsect2>
 539  </refsect1>
 540
 541
 542  <refsect1>
 543   <title>See Also</title>
 544
 545   <para>
 546    <xref linkend="app-postgres">
 547   </para>
 548  </refsect1>
 549
 550 </refentry>