Keep-alive connections parameters

PostgreSQL® keep-alive connection parameters are useful to manage Idle connections. The following is a reference to the default Aiven for PostgreSQL® parameters on the server side, and what keep-alive parameters can be used at the client side.

Keep-alive server side parameters

Currently, the following default keep-alive timeouts are used on the server-side:

Parameter (server)	Value	Description
tcp_keepalives_idle	180	Specifies the amount of time with no network activity after which the operating system should send a TCP keepalive message to the client.
tcp_keepalives_count	6	Specifies the number of TCP keepalive messages that can be lost before the server’s connection to the client is considered dead.
tcp_keepalives_interval	10	Specifies the amount of time after which a TCP keepalive message that has not been acknowledged by the client should be retransmitted.

Keep-alive client side parameters

The client-side keep-alive parameters can be set to whatever values you want.

Parameter (client)	Description
keepalives	Controls whether client-side TCP keepalives are used. The default value is 1, meaning on.
keepalives_idle	Controls the number of seconds of inactivity after which TCP should send a keepalive message to the server.
keepalive_count	Controls the number of TCP keepalives that can be lost before the client’s connection to the server is considered dead.
keepalives_interval	Controls the number of seconds after which a TCP keepalive message that is not acknowledged by the server should be retransmitted.

Even though TCP connections usually stay open for extended periods of time, you should also make sure that your applications can reconnect, since TCP connections are liable to break at times. Also, when reconnecting you should make sure that your client always resolves the DNS address on connection, since the underlying address will change during automatic failover when a primary node fails.