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By setting this parameter to 0, this is turned off.","BodyHTML":"\u003cdiv\u003e\u003cdl\u003e\u003cdt id=\"LIBPQ-CONNECT-SSLSNI\"\u003e\u003cspan\u003e\u003ccode\u003esslsni\u003c/code\u003e\u003c/span\u003e \u003c/dt\u003e\u003cdd\u003e\n\u003cp\u003eIf set to 1 (default), libpq sets the TLS extension \u003cspan\u003e“\u003cspan\u003eServer Name Indication\u003c/span\u003e”\u003c/span\u003e (SNI) on SSL-enabled connections. By setting this parameter to 0, this is turned off.\u003c/p\u003e\n\u003cp\u003eThe Server Name Indication can be used by SSL-aware proxies to route connections without having to decrypt the SSL stream. (Note that unless the proxy is aware of the PostgreSQL protocol handshake this would require setting \u003ccode\u003esslnegotiation\u003c/code\u003e to \u003ccode\u003edirect\u003c/code\u003e.) However, SNI makes the destination host name appear in cleartext in the network traffic, so it might be undesirable in some cases.\u003c/p\u003e\n\u003c/dd\u003e\u003c/dl\u003e\u003c/div\u003e","SourceRevision":"ee8d1a3612338fd9adf250730cb640fcc5233b5491337cc00a316a44e3a0b9f8","ContentHash":"e9090861bdf2b7c2c36b258438ff2010304b96ab9f6818345ec0fe0ccad85115","Payload":{"description":["If set to 1 (default), libpq sets the TLS extension “ Server Name Indication ” ( SNI ) on SSL-enabled connections. By setting this parameter to 0, this is turned off."],"manual_html":"\u003cdiv\u003e\u003cdl class=\"variablelist\"\u003e\u003cdt id=\"LIBPQ-CONNECT-SSLSNI\"\u003e\u003cspan class=\"term\"\u003e\u003ccode class=\"literal\"\u003esslsni\u003c/code\u003e\u003c/span\u003e \u003c/dt\u003e\u003cdd\u003e\n\u003cp\u003eIf set to 1 (default), libpq sets the TLS extension \u003cspan class=\"quote\"\u003e“\u003cspan class=\"quote\"\u003eServer Name Indication\u003c/span\u003e”\u003c/span\u003e (SNI) on SSL-enabled connections. By setting this parameter to 0, this is turned off.\u003c/p\u003e\n\u003cp\u003eThe Server Name Indication can be used by SSL-aware proxies to route connections without having to decrypt the SSL stream. (Note that unless the proxy is aware of the PostgreSQL protocol handshake this would require setting \u003ccode class=\"literal\"\u003esslnegotiation\u003c/code\u003e to \u003ccode class=\"literal\"\u003edirect\u003c/code\u003e.) However, SNI makes the destination host name appear in cleartext in the network traffic, so it might be undesirable in some cases.\u003c/p\u003e\n\u003c/dd\u003e\u003c/dl\u003e\u003c/div\u003e","related":[{"label":"Connection service file","url":"/docs/18/libpq-pgservice.html"},{"label":"Password file","url":"/docs/18/libpq-pgpass.html"},{"label":"All libpq environment variables","url":"/docs/18/libpq-envars.html"}],"sections":[{"paragraphs":["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. 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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."],"title":"Default resolution and service-file precedence"},{"paragraphs":["PGSSLSNI behaves the same as the sslsni connection parameter."],"title":"Environment variable evidence"}],"tables":[{"columns":[{"key":"name","label":"Variable"},{"key":"description","label":"Documented behavior"}],"key":"environment","rows":[{"description":"PGSSLSNI behaves the same as the sslsni connection parameter.","name":{"text":"PGSSLSNI","url":"/docs/18/libpq-envars.html"}}],"title":"Environment fallback"}]}},"RequestedLocale":"zh-Hans","Fallback":true,"Versions":["14","15","16","17","18","19","20"],"Locales":["en"],"Signatures":null,"Spellings":null,"SQLState":null,"Evidence":null}