Creating DH parameters for additional security. This may take a very long time. There will be another message once this process is completed Generating DH parameters, 2048 bit long safe prime, generator 2 This is going to take a long time
Yeah, the dhparams part can take a long time (up to 2 hours on an arm box) or it could be 10 seconds, that's cryptography for you
For those using an arm device If you don't want to wait always can generate the dhparams.pem in other machine with:
$ openssl dhparam -out dhparams.pem 2048
and then, in this case, copy the resulting file to:
Any modern x64 PC will complete this operation in less than a minute instead of hours.
Once you copy the file there, each time the container is started it's init scripts will check if is already there and skip this step unless you change the default DHLEVEL Only then needs to be regenerated.