When a server instance is configured to use HTTPS, it generates an ephemeral DH key at startup. Generating the DH key at startup provides more security than reading it from a file on disk. However, this can add a couple of minutes to a server instance's startup time.
If you need the server instance to startup without delay and
are not concerned about the loss of security, you can configure the
server instance to read the ephemeral DH key from a file using the ssl-tmp-dh-param configuration
property. The ssl-tmp-dh-param property specifies
the file storing the DH key in PEM format.