Specifies a connection string to be used for the standby server
to connect with the primary. This string is in the format
accepted by the libpq PQconnectdb
function,
described in Section 31.1. If any option is
unspecified in this string, then the corresponding environment
variable (see Section 31.13) is checked. If the
environment variable is not set either, then
defaults are used.
The connection string should specify the host name (or address)
of the primary server, as well as the port number if it is not
the same as the standby server's default.
Also specify a user name corresponding to a role that has the
REPLICATION and LOGIN privileges on the
primary (see
Section 25.2.5.1).
A password needs to be provided too, if the primary demands password
authentication. It can be provided in the
primary_conninfo string, or in a separate
~/.pgpass file on the standby server (use
replication as the database name).
Do not specify a database name in the
primary_conninfo string.
This setting has no effect if standby_mode is off.