/usr/bin/nsd-checkconf: invalid option -- '-'
usage: nsd-checkconf [-v|-h] [-o option] [-z zonename]
                     [-s keyname] [-t tlsauthname] <configfilename>
       Checks NSD configuration file for errors.
       Version 4.15.4. Report bugs to <https://github.com/NLnetLabs/nsd/issues or nsd-bugs@nlnetlabs.nl>.

Use with a configfile as argument to check syntax.
Use with -o, -z, -t or -s options to query the configuration.

-v			Verbose, echo settings that take effect to std output.
-h			Print this help information.
-f			Use with -o to print final pathnames, ie. with chroot.
-o option		Print value of the option specified to stdout.
-p pattern		Print option value for the pattern given.
-z zonename		Print option value for the zone given.
-a keyname		Print algorithm name for the TSIG key.
-s keyname		Print base64 secret blob for the TSIG key.
-t tls-auth-name	Print auth domain name for the tls-auth clause.