pg_ctlpg_ctl1Applicationpg_ctlinitialize, start, stop, or control a PostgreSQL serverpg_ctldatadirinitdb-optionspg_ctlsecondsdatadirfilenameoptionspathpg_ctlsecondsdatadirpg_ctlsecondsdatadiroptionspg_ctldatadirpg_ctldatadirpg_ctldatadirpg_ctlsignal_nameprocess_idpg_ctlservicenameusernamepassworddatadirsecondsoptionspg_ctlservicenameDescriptionpg_ctl is a utility for initializing a
PostgreSQL database cluster, starting,
stopping, or restarting the PostgreSQL
database server (), or displaying the
status of a running 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.
The or mode creates a new
PostgreSQL database cluster. A database
cluster is a collection of databases that are managed by a single
server instance. This mode invokes the initdb
command. See for details.
In mode, a new server is launched. The
server is started in the background, and its standard input is attached
to /dev/null (or nul> on Windows).
On Unix-like systems, by default, the server's standard output and
standard error are sent to pg_ctl's
standard output (not standard error). The standard output of
pg_ctl should then 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. On
Windows, by default the server's standard output and standard error
are sent to the terminal. These default behaviors can be changed
by using to append the server's output to a log file.
Use of either or output redirection is recommended.
In mode, the server that is running in
the specified data directory is shut down. Three different
shutdown methods can be selected with the
option. Smart mode (the default) waits for all active
clients to disconnect and any online backup to finish.
If the server is in hot standby, recovery and streaming replication
will be terminated once all clients have disconnected.
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 immediately, without a clean shutdown.
This will lead to a crash-recovery run on the next restart.
mode effectively executes a stop followed
by a start. This allows changing the postgres
command-line options. might fail if
relative paths specified were specified on the command-line during
server start.
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.
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. If the server is not running, the process returns an
exit status of 3. If an accessible data directory is not specified,
the process returns an exit status of 4.
In mode, the standby server that is
running in the specified data directory is commanded to exit
recovery and begin read-write operations.
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.
mode allows you to register a system service
on Microsoft Windows>. The option
allows selection of service start type, either auto (start
service automatically on system startup) or demand (start
service on demand).
mode allows you to unregister a system service
on Microsoft Windows>. This undoes the effects of the
command.
Options
Attempt to allow server crashes to produce core files, on platforms
where this is possible, by lifting any soft resource limit placed on
core files.
This is useful in debugging or diagnosing problems by allowing a
stack trace to be obtained from a failed server process.
Specifies the file system location of the database configuration files. If
this is omitted, the environment variable
PGDATA is used.
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 is disallowed to other users by default.
Specifies the shutdown mode. mode
can be smart, fast, or
immediate, or the first letter of one of
these three. If this is omitted, smart is used.
Specifies options to be passed directly to the
postgres command.
The options should usually be surrounded by single or double
quotes to ensure that they are passed through as a group.
Specifies options to be passed directly to the
initdb command.
The options should usually be surrounded by single or double
quotes to ensure that they are passed through as a group.
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.
In init mode, this option analogously
specifies the location of the initdb
executable.
Print only errors, no informational messages.
The maximum number of seconds to wait when waiting for startup or
shutdown to complete. The default is 60 seconds.
Print the pg_ctl version and exit.
Wait for the startup or shutdown to complete.
Waiting is the default option for shutdowns, but not startups.
When waiting for startup, pg_ctl repeatedly
attempts to connect to the server.
When waiting for shutdown, pg_ctl waits for
the server to remove its PID file.
This option allows the entry of an SSL> passphrase on startup.
pg_ctl returns an exit code based on the
success of the startup or shutdown.
Do not wait for startup or shutdown to complete. This is the
default for start and restart modes.
Show help about pg_ctl command line
arguments, and exit.
Options for Windows
Name of the event source for pg_ctl to use
for logging to the event log when running as a Windows service. The
default is PostgreSQL. Note that this only controls
the logging from pg_ctl itself - once
started, the server will use the event source specified
by . Should the server fail during
early startup, it may also log using the default event
source PostgreSQL.
Name of the system service to register. The name will be used
as both the service name and the display name.
Password for the user to start the service.
Start type of the system service to register. start-type can
be auto, or demand, or
the first letter of one of these two. If this is omitted,
auto is used.
User name for the user to start the service. For domain users, use the
format DOMAIN\username.
EnvironmentPGDATA
Default data directory location.
pg_ctl, like most other PostgreSQL>
utilities,
also uses the environment variables supported by libpq>
(see ).
For additional server variables, see .
Filespostmaster.pid
The existence of this file in the data directory is used to help
pg_ctl determine if the server is
currently running.
postmaster.optsIf this file exists in the data directory,
pg_ctl (in mode)
will pass the contents of the file as options to
postgres, unless overridden
by the option. The contents of this file
are also displayed in mode.
ExamplesStarting the Server
To start the server:
$pg_ctl start
To start the server, waiting until the server is
accepting connections:
$pg_ctl -w start
To start the server using port 5433, and
running without fsync, use:
$pg_ctl -o "-F -p 5433" startStopping the Server
To stop the server, use:
$pg_ctl stop
The option allows control over
how the server shuts down:
$pg_ctl stop -m fastRestarting 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 the server,
waiting for it to shut down and restart:
$pg_ctl -w restart
To restart using port 5433, disabling fsync> upon restart:
$pg_ctl -o "-F -p 5433" restartShowing the Server Status
Here is sample status output from
pg_ctl:
$pg_ctl status
pg_ctl: server is running (PID: 13718)
/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