PG_CTL(1)                                                 PostgreSQL Server Applications                                                 PG_CTL(1)

NAME

       pg_ctl - start, stop, or restart a PostgreSQL server

SYNOPSIS

       pg_ctl start [ -w ]  [ -t seconds ]  [ -s ]  [ -D datadir ]  [ -l filename ]  [ -o options ]  [ -p path ]  [ -c ]

       pg_ctl stop [ -W ]  [ -t seconds ]  [ -s ]  [ -D datadir ]  [ -m
         [ s[mart] ]  [ f[ast] ]  [ i[mmediate] ]
        ]

       pg_ctl restart [ -w ]  [ -t seconds ]  [ -s ]  [ -D datadir ]  [ -c ]  [ -m
         [ s[mart] ]  [ f[ast] ]  [ i[mmediate] ]
        ]  [ -o options ]

       pg_ctl reload [ -s ]  [ -D datadir ]

       pg_ctl status [ -D datadir ]

       pg_ctl kill [ signal_name ]  [ process_id ]

       pg_ctl register [ -N servicename ]  [ -U username ]  [ -P password ]  [ -D datadir ]  [ -w ]  [ -t seconds ]  [ -o options ]

       pg_ctl unregister [ -N servicename ]

DESCRIPTION

       pg_ctl  is  a utility for starting, stopping, or restarting the PostgreSQL backend server (postgres(1)), or displaying the status of a run-
       ning server. Although the server can be started manually, pg_ctl encapsulates tasks such as redirecting log output and  properly  detaching
       from the terminal and process group. It also provides convenient options for controlled shutdown.

       In start mode, a new server is launched. The server is started in the background, and standard input is attached to /dev/null. The standard
       output and standard error are either appended to a log file (if the -l option is used), or redirected  to  pg_ctl's  standard  output  (not
       standard error). If no log file is chosen, the standard output of pg_ctl should be redirected to a file or piped to another process such as
       a log rotating program like rotatelogs; otherwise postgres will write its output to the controlling terminal (from the background) and will
       not leave the shell's process group.

       In  stop  mode,  the  server that is running in the specified data directory is shut down. Three different shutdown methods can be selected
       with the -m option: ``Smart'' mode waits for online backup mode to finish and all the clients to disconnect. This is the default.  ``Fast''
       mode  does  not wait for clients to disconnect and will terminate an online backup in progress. All active transactions are rolled back and
       clients are forcibly disconnected, then the server is shut down. ``Immediate'' mode will abort all server processes without a  clean  shut-
       down. This will lead to a recovery run on restart.

       restart mode effectively executes a stop followed by a start. This allows changing the postgres command-line options.

       reload  mode simply sends the postgres process a SIGHUP signal, causing it to reread its configuration files (postgresql.conf, pg_hba.conf,
       etc.). This allows changing of configuration-file options that do not require a complete restart to take effect.

       status mode checks whether a server is running in the specified data directory. If it is, the PID and the command line  options  that  were
       used to invoke it are displayed.

       kill  mode  allows  you  to send a signal to a specified process. This is particularly valuable for Microsoft Windows which does not have a
       kill command. Use --help to see a list of supported signal names.

       register mode allows you to register a system service on Microsoft Windows.

       unregister mode allows you to unregister a system service on Microsoft Windows, previously registered with the register command.

OPTIONS

       -c     Attempt to allow server crashes to produce core files, on platforms where this available, by lifting any soft resource limit  placed
              on them.  This is useful in debugging or diagnosing problems by allowing a stack trace to be obtained from a failed server process.

       -D datadir
              Specifies the file system location of the database files. If this is omitted, the environment variable PGDATA is used.

       -l filename
              Append  the  server log output to filename. If the file does not exist, it is created. The umask is set to 077, so access to the log
              file from other users is disallowed by default.

       -m mode
              Specifies the shutdown mode. mode can be smart, fast, or immediate, or the first letter of one of these three.

       -o options
              Specifies options to be passed directly to the postgres command.

              The options are usually surrounded by single or double quotes to ensure that they are passed through as a group.

       -p path
              Specifies the location of the postgres executable. By default the postgres executable is taken from the same directory as pg_ctl, or
              failing  that,  the hard-wired installation directory. It is not necessary to use this option unless you are doing something unusual
              and get errors that the postgres executable was not found.

       -s     Only print errors, no informational messages.

       -t     The number of seconds to wait when waiting for start or shutdown to complete.

       -w     Wait for the start or shutdown to complete. The default wait time is 60 seconds. This is the default option for  shutdowns.  A  suc-
              cessful  shutdown  is  indicated  by  removal  of the PID file. For starting up, a successful psql -l indicates success. pg_ctl will
              attempt to use the proper port for psql. If the environment variable PGPORT exists, that is used. Otherwise, it will see if  a  port
              has  been  set  in the postgresql.conf file.  If neither of those is used, it will use the default port that PostgreSQL was compiled
              with (5432 by default). When waiting, pg_ctl will return an accurate exit code based on the success of the startup or shutdown.

       -W     Do not wait for start or shutdown to complete. This is the default for starts and restarts.

   OPTIONS FOR WINDOWS
       -N servicename
              Name of the system service to register. The name will be used as both the service name and the display name.

       -P password
              Password for the user to start the service.

       -U username
              User name for the user to start the service. For domain users, use the format DOMAINusername.

ENVIRONMENT

       PGDATA Default data directory location.

       PGPORT Default port for psql(1) (used by the -w option).

       For additional server variables, see postgres(1).  This utility, like most other PostgreSQL utilities, also uses the environment  variables
       supported by libpq (see in the documentation).

FILES

       postmaster.pid
              The existence of this file in the data directory is used to help pg_ctl determine if the server is currently running or not.

       postmaster.opts
              If  this  file  exists  in  the  data directory, pg_ctl (in restart mode) will pass the contents of the file as options to postgres,
              unless overridden by the -o option. The contents of this file are also displayed in status mode.

       postgresql.conf
              This file, located in the data directory, is parsed to find the proper port to use with psql when the -w is given in start mode.

NOTES

       Waiting for complete start is not a well-defined operation and might fail if access control is set up so that a local client cannot connect
       without  manual  interaction  (e.g., password authentication). For additional connection variables, see in the documentation, and for pass-
       words, also see in the documentation.

EXAMPLES

   STARTING THE SERVER
       To start up a server:

       $ pg_ctl start

       An example of starting the server, blocking until the server has come up is:

       $ pg_ctl -w start

       For a server using port 5433, and running without fsync, use:

       $ pg_ctl -o "-F -p 5433" start

   STOPPING THE SERVER
       $ pg_ctl stop

       stops the server. Using the -m switch allows one to control how the backend shuts down.

   RESTARTING THE SERVER
       Restarting the server is almost equivalent to stopping the server and starting it again except that pg_ctl saves  and  reuses  the  command
       line options that were passed to the previously running instance. To restart the server in the simplest form, use:

       $ pg_ctl restart

       To restart server, waiting for it to shut down and to come up:

       $ pg_ctl -w restart

       To restart using port 5433 and disabling fsync after restarting:

       $ pg_ctl -o "-F -p 5433" restart

   SHOWING THE SERVER STATUS
       Here is a sample status output from pg_ctl:

       $ pg_ctl status
       pg_ctl: server is running (pid: 13718)
       Command line was:
       /usr/local/pgsql/bin/postgres '-D' '/usr/local/pgsql/data' '-p' '5433' '-B' '128'

       This is the command line that would be invoked in restart mode.

SEE ALSO

       postgres(1)

Application                                                         2010-05-14                                                           PG_CTL(1)