dnssec-keygen: invalid argument --
Usage:
    dnssec-keygen [options] name

Version: 9.20.30
    name: owner of the key
Options:
    -K <directory>: write keys into directory
    -k <policy>: generate keys for dnssec-policy
    -l <file>: configuration file with dnssec-policy statement
    -a <algorithm>:
        RSASHA1 (deprecated) | NSEC3RSASHA1 (deprecated) |
        RSASHA256 | RSASHA512 |
        ECDSAP256SHA256 | ECDSAP384SHA384 |
        ED25519 | ED448
    -3: use NSEC3-capable algorithm
    -b <key size in bits>:
        RSASHA1 (deprecated) :	[1024..4096]
        NSEC3RSASHA1 (deprecated) :	[1024..4096]
        RSASHA256:	[1024..4096]
        RSASHA512:	[1024..4096]
        ECDSAP256SHA256:	ignored
        ECDSAP384SHA384:	ignored
        ED25519:	ignored
        ED448:	ignored
        (key size defaults are set according to
        algorithm and usage (ZSK or KSK)
    -n <nametype>: ZONE | HOST | ENTITY | USER | OTHER
        (DNSKEY generation defaults to ZONE)
    -c <class>: (default: IN)
    -d <digest bits> (0 => max, default)
    -E <engine>:
        name of an OpenSSL engine to use
    -f <keyflag>: ZSK | KSK | REVOKE
    -F: FIPS mode
    -L <ttl>: default key TTL
    -M <min>:<max>: allowed Key ID range
    -p <protocol>: (default: 3 [dnssec])
    -s <strength>: strength value this key signs DNS records with (default: 0)
    -T <rrtype>: DNSKEY | KEY (default: DNSKEY; use KEY for SIG(0))
    -t <type>: AUTHCONF | NOAUTHCONF | NOAUTH | NOCONF (default: AUTHCONF)
    -h: print usage and exit
    -m <memory debugging mode>:
       usage | trace | record
    -v <level>: set verbosity level (0 - 10)
    -V: print version information
Timing options:
    -P date/[+-]offset/none: set key publication date (default: now)
    -P sync date/[+-]offset/none: set CDS and CDNSKEY publication date
    -A date/[+-]offset/none: set key activation date (default: now)
    -R date/[+-]offset/none: set key revocation date
    -I date/[+-]offset/none: set key inactivation date
    -D date/[+-]offset/none: set key deletion date
    -D sync date/[+-]offset/none: set CDS and CDNSKEY deletion date
    -G: generate key only; do not set -P or -A
    -C: generate a backward-compatible key, omitting all dates
    -S <key>: generate a successor to an existing key
    -i <interval>: prepublication interval for successor key (default: 30 days)
Output:
     K<name>+<alg>+<id>.key, K<name>+<alg>+<id>.private