This is nbd-server version 3.15.2

nbd-server: unrecognized option '--help' This is nbd-server version 3.15.2 Usage: [ip:|ip6@]port file_to_export [size][kKmM] [-l authorize_file] [-r] [-m] [-c] [-C configuration file] [-p PID file name] [-o section name] [-M max connections] [-V] -r|--read-only read only -m|--multi-file multiple file -c|--copy-on-write copy on write -C|--config-file specify an alternate configuration file -l|--authorize-file file with list of hosts that are allowed to connect. -p|--pid-file specify a filename to write our PID to -o|--output-config output a config file section for what you specified on the command line, with the specified section name -M|--max-connections specify the maximum number of opened connections -V|--version output the version and exit if port is set to 0, stdin is used (for running from inetd). if file_to_export contains '%s', it is substituted with the IP address of the machine trying to connect if ip is set, it contains the local IP address on which we're listening. if not, the server will listen on all local IP addresses Using configuration file /etc/nbd-server/config