PostgreSQL version:

ssl_dh_params_file

Specifies the name of the file containing Diffie-Hellman parameters used for so-called ephemeral DH family of SSL ciphers. The default is empty, in which case compiled-in default DH parameters used. Using custom DH parameters reduces the exposure if an attacker manages to crack the well-known compiled-in DH parameters. You can create your own DH parameters file with the command openssl dhparam -out dhparams.pem 2048.

This parameter can only be set in the postgresql.conf file or on the server command line.

Recommendations

According to your SSL configuration, which maybe provided by your installer.

Comments