openssl dhparam -help

[saolasosme]

Diffie-Hellman Parameter Management. Obsoleted by dhparam(1).

Generation and Management of Diffie-Hellman Parameters. Superseded by genpkey(1) and pkeyparam(1).

$ openssl dhparam -help
Usage: dhparam [flags] [numbits]
Valid options are:
 -help               Display this summary
 -in infile          Input file
 -inform PEM|DER     Input format, DER or PEM
 -outform PEM|DER    Output format, DER or PEM
 -out outfile        Output file
 -check              Check the DH parameters
 -text               Print a text form of the DH parameters
 -noout              Don't output any DH parameters
 -rand val           Load the file(s) into the random number generator
 -writerand outfile  Write random data to the specified file
 -C                  Print C code
 -2                  Generate parameters using 2 as the generator value
 -5                  Generate parameters using 5 as the generator value
 -dsaparam           Read or generate DSA parameters, convert to DH
 -engine val         Use engine e, possibly a hardware device