You want to set the maximum time to complete client authentication to 10 seconds. Which parameter should you configure?

The authenticationtimeout parameter is the specific server setting in PostgreSQL used to control the maximum time allowed for a client to complete the authentication process. The value is specified in seconds. Setting authenticationtimeout = 10s in the postgresql.conf file ensures that if a client does not successfully authenticate within 10 seconds of connecting, the server will close the connection. This prevents connections from lingering indefinitely in the authentication phase, which is a crucial security and resource management measure.

B. authtimeout is not a valid or recognized server configuration parameter in PostgreSQL.

C. clienttimeout is a deprecated alias for statementtimeout, which governs the maximum duration for any single SQL statement, not the authentication process.

D. connectiontimeout is a client-side connection string parameter used to set a timeout for establishing the initial network connection, not a server-side authentication setting.

1. PostgreSQL 16 Documentation, Chapter 20. Server Configuration, Section 20.4. Connection and Authentication:

Parameter: authenticationtimeout (integer)

Description: "Maximum time to complete client authentication, in seconds. If a client has not completed the authentication protocol in this much time, the server closes the connection. This prevents stuck clients from occupying a connection indefinitely. The default is one minute (1m)."

Source: PostgreSQL Documentation: Connection Settings

2. PostgreSQL 16 Documentation, Chapter 20. Server Configuration, Section 20.11. Client Connection Defaults:

Parameter: statementtimeout (integer)

Description: "Abort any statement that takes more than the specified amount of time... A value of zero (the default) turns this off. The clienttimeout setting is a deprecated alias for this." (This confirms option C is incorrect).

Source: PostgreSQL Documentation: Client Connection Defaults

3. PostgreSQL 16 Documentation, Chapter 34. libpq - C Library, Section 34.2. Database Connection Control Functions:

Parameter: connecttimeout

Description: "Maximum time to wait for connection, in seconds (write as a decimal integer string). Zero, negative, or not specified means wait indefinitely. The minimum timeout is 2 seconds. This timeout applies to each host name or IP address individually." (This confirms connectiontimeout is a client-side concept, referenced here as connecttimeout in libpq).

Source: PostgreSQL Documentation: libpq Connection Strings