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sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a033.18 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n
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sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a034.18 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n
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sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a033.18 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 33.18 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "38794556e5c17260bc16d5edeadb50f04215a636905a7d42df500810e55cd5c2", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/13/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a033.18 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 33.18 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "38794556e5c17260bc16d5edeadb50f04215a636905a7d42df500810e55cd5c2", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/14/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a034.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 34.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "4d20c905793a5b4ccea1d7d61f7e0b9ae13e62051c1892e4f266befa09d319cd", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/15/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a034.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/16/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a034.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 34.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/17/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a032.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "8cee88b057502e1ab1559e9a8b0b8bdc555df07335cf7edfdd1c462963812a19", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/18/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a032.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "8cee88b057502e1ab1559e9a8b0b8bdc555df07335cf7edfdd1c462963812a19", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified using the servicefile key word in a libpq connection string or by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/19/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a032.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "8cee88b057502e1ab1559e9a8b0b8bdc555df07335cf7edfdd1c462963812a19", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified using the servicefile key word in a libpq connection string or by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/devel/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a032.18 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.18 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "dede55281820600f051891279d911d3d76ecda6a0ffaaf5c1318682e4324bea7", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . 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These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, {"title": "Environment variable evidence", "paragraphs": ["PGSSLMODE behaves the same as the sslmode connection parameter."]}], "signature": "sslmode", "documented": true, "description": ["This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:"], "environment": [{"name": "PGSSLMODE", "source_url": "/docs/18/libpq-envars.html", "description": "PGSSLMODE behaves the same as the sslmode connection parameter."}], "manual_html": "
sslmode
\n

This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes:

\n
\n
\n
disable
\n
\n

only try a non-SSL connection

\n
\n
allow
\n
\n

first try a non-SSL connection; if that fails, try an SSL connection

\n
\n
prefer (default)
\n
\n

first try an SSL connection; if that fails, try a non-SSL connection

\n
\n
require
\n
\n

only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified

\n
\n
verify-ca
\n
\n

only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority (CA)

\n
\n
verify-full
\n
\n

only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate

\n
\n
\n
\n

See Section\u00a032.19 for a detailed description of how these options work.

\n

sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require, verify-ca, or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection.

\n

Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode. To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable.

\n
", "manual_path": "libpq-connect.html#LIBPQ-CONNECT-SSLMODE", "source_option": {"keyword": "sslmode", "declaration": "\"sslmode\", \"PGSSLMODE\", DefaultSSLMode, NULL, \"SSL-Mode\", \"\", 12, offsetof(struct pg_conn, sslmode)", "environment": "PGSSLMODE", "source_notes": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_data": {"keyword": "sslmode", "definition": "This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .", "documented": true, "environment": "PGSSLMODE", "default_evidence": [], "compiled_default_expression": "DefaultSSLMode"}, "comparison_hash": "8cee88b057502e1ab1559e9a8b0b8bdc555df07335cf7edfdd1c462963812a19", "default_evidence": [], "precedence_evidence": ["The following environment variables can be used to select default connection parameter values, which will be used by PQconnectdb , PQsetdbLogin and PQsetdb if no value is directly specified by the calling code. These are useful to avoid hard-coding database connection information into simple client applications, for example.", "Service names can be defined in either a per-user service file or a system-wide file. If the same service name exists in both the user and the system file, the user file takes precedence. By default, the per-user service file is named ~/.pg_service.conf . 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For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "comparison": {"left": "19", "right": "20", "status": "changed", "diff": "--- PostgreSQL 19\n+++ PostgreSQL 20\n@@ -1,7 +1,7 @@\n {\n \"compiled_default_expression\": \"DefaultSSLMode\",\n \"default_evidence\": [],\n- \"definition\": \"This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.19 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .\",\n+ \"definition\": \"This option determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server. There are six modes: disable only try a non- SSL connection allow first try a non- SSL connection; if that fails, try an SSL connection prefer (default) first try an SSL connection; if that fails, try a non- SSL connection require only try an SSL connection. If a root CA file is present, verify the certificate in the same way as if verify-ca was specified verify-ca only try an SSL connection, and verify that the server certificate is issued by a trusted certificate authority ( CA ) verify-full only try an SSL connection, verify that the server certificate is issued by a trusted CA and that the requested server host name matches that in the certificate See Section 32.18 for a detailed description of how these options work. sslmode is ignored for Unix domain socket communication. If PostgreSQL is compiled without SSL support, using options require , verify-ca , or verify-full will cause an error, while options allow and prefer will be accepted but libpq will not actually attempt an SSL connection. Note that if GSSAPI encryption is possible, that will be used in preference to SSL encryption, regardless of the value of sslmode . To force use of SSL encryption in an environment that has working GSSAPI infrastructure (such as a Kerberos server), also set gssencmode to disable .\",\n \"documented\": true,\n \"environment\": \"PGSSLMODE\",\n \"keyword\": \"sslmode\""}}