PG_ISREADY(1) PostgreSQL 9.5.5 Documentation PG_ISREADY(1)
pg_isready – check the connection status of a PostgreSQL server
pg_isready [connection-option…] [option…]
pg_isready is a utility for checking the connection status of a
PostgreSQL database server. The exit status specifies the result of the
Specifies the name of the database to connect to.
If this parameter contains an = sign or starts with a valid URI
prefix (postgresql:// or postgres://), it is treated as a conninfo
string. See Section 31.1.1, “Connection Strings”, in the
documentation for more information.
Specifies the host name of the machine on which the server is
running. If the value begins with a slash, it is used as the
directory for the Unix-domain socket.
Specifies the TCP port or the local Unix-domain socket file
extension on which the server is listening for connections.
Defaults to the value of the PGPORT environment variable or, if not
set, to the port specified at compile time, usually 5432.
Do not display status message. This is useful when scripting.
The maximum number of seconds to wait when attempting connection
before returning that the server is not responding. Setting to 0
disables. The default is 3 seconds.
Connect to the database as the user username instead of the
Print the pg_isready version and exit.
Show help about pg_isready command line arguments, and exit.
pg_isready returns 0 to the shell if the server is accepting
connections normally, 1 if the server is rejecting connections (for
example during startup), 2 if there was no response to the connection
attempt, and 3 if no attempt was made (for example due to invalid
pg_isready, like most other PostgreSQL utilities, also uses the
environment variables supported by libpq (see Section 31.14,
“Environment Variables”, in the documentation).
It is not necessary to supply correct user name, password, or database
name values to obtain the server status; however, if incorrect values
are provided, the server will log a failed connection attempt.
/tmp:5432 – accepting connections
$ echo $?
Running with connection parameters to a PostgreSQL cluster in startup:
$ pg_isready -h localhost -p 5433
localhost:5433 – rejecting connections
$ echo $?
Running with connection parameters to a non-responsive PostgreSQL
$ pg_isready -h someremotehost
someremotehost:5432 – no response
$ echo $?
PostgreSQL 9.5.5 2016 PG_ISREADY(1)