Selects the cryptographic algorithm. The value of algorithm must be one of RSASHA1, NSEC3RSASHA1, RSASHA256, RSASHA512, ECDSAP256SHA256, ECDSAP384SHA384, ED25519 or ED448.

If no algorithm is specified, then RSASHA1 will be used by default, unless the -3 option is specified, in which case NSEC3RSASHA1 will be used instead. (If -3 is used and an algorithm is specified, that algorithm will be checked for compatibility with NSEC3.)

These values are case insensitive. In some cases, abbreviations are supported, such as ECDSA256 for ECDSAP256SHA256 and ECDSA384 for ECDSAP384SHA384. If RSASHA1 is specified along with the -3 option, then NSEC3RSASHA1 will be used instead.

As of BIND 9.12.0, this option is mandatory except when using the -S option (which copies the algorithm from the predecessory key). Previously, the default for newly generated keys was RSASHA1.

Use an NSEC3-capable algorithm to generate a DNSSEC key. If this option is used with an algorithm that has both NSEC and NSEC3 versions, then the NSEC3 version will be used; for example, dnssec-keygen -3a RSASHA1 specifies the NSEC3RSASHA1 algorithm.

Specifies the cryptographic hardware to use.

When BIND is built with OpenSSL PKCS#11 support, this defaults to the string "pkcs11", which identifies an OpenSSL engine that can drive a cryptographic accelerator or hardware service module. When BIND is built with native PKCS#11 cryptography (--enable-native-pkcs11), it defaults to the path of the PKCS#11 provider library specified via "--with-pkcs11".

Specifies the label for a key pair in the crypto hardware.

When BIND 9 is built with OpenSSL-based PKCS#11 support, the label is an arbitrary string that identifies a particular key. It may be preceded by an optional OpenSSL engine name, followed by a colon, as in "pkcs11:keylabel".

When BIND 9 is built with native PKCS#11 support, the label is a PKCS#11 URI string in the format "pkcs11:keyword=value[;keyword=value;...]" Keywords include "token", which identifies the HSM; "object", which identifies the key; and "pin-source", which identifies a file from which the HSM's PIN code can be obtained. The label will be stored in the on-disk "private" file.

If the label contains a pin-source field, tools using the generated key files will be able to use the HSM for signing and other operations without any need for an operator to manually enter a PIN. Note: Making the HSM's PIN accessible in this manner may reduce the security advantage of using an HSM; be sure this is what you want to do before making use of this feature.

Specifies the owner type of the key. The value of nametype must either be ZONE (for a DNSSEC zone key (KEY/DNSKEY)), HOST or ENTITY (for a key associated with a host (KEY)), USER (for a key associated with a user(KEY)) or OTHER (DNSKEY). These values are case insensitive.

Compatibility mode: generates an old-style key, without any metadata. By default, dnssec-keyfromlabel will include the key's creation date in the metadata stored with the private key, and other dates may be set there as well (publication date, activation date, etc). Keys that include this data may be incompatible with older versions of BIND; the -C option suppresses them.

Indicates that the DNS record containing the key should have the specified class. If not specified, class IN is used.

Set the specified flag in the flag field of the KEY/DNSKEY record. The only recognized flags are KSK (Key Signing Key) and REVOKE.

Generate a key, but do not publish it or sign with it. This option is incompatible with -P and -A.

Prints a short summary of the options and arguments to dnssec-keyfromlabel.

Sets the directory in which the key files are to be written.

Generate KEY records rather than DNSKEY records.

Sets the default TTL to use for this key when it is converted into a DNSKEY RR. If the key is imported into a zone, this is the TTL that will be used for it, unless there was already a DNSKEY RRset in place, in which case the existing TTL would take precedence. Setting the default TTL to 0 or none removes it.

Sets the protocol value for the key. The protocol is a number between 0 and 255. The default is 3 (DNSSEC). Other possible values for this argument are listed in RFC 2535 and its successors.

Generate a key as an explicit successor to an existing key. The name, algorithm, size, and type of the key will be set to match the predecessor. The activation date of the new key will be set to the inactivation date of the existing one. The publication date will be set to the activation date minus the prepublication interval, which defaults to 30 days.

Indicates the use of the key. type must be one of AUTHCONF, NOAUTHCONF, NOAUTH, or NOCONF. The default is AUTHCONF. AUTH refers to the ability to authenticate data, and CONF the ability to encrypt data.

Sets the debugging level.

Prints version information.

Allows DNSSEC key files to be generated even if the key ID would collide with that of an existing key, in the event of either key being revoked. (This is only safe to use if you are sure you won't be using RFC 5011 trust anchor maintenance with either of the keys involved.)

Sets the date on which a key is to be published to the zone. After that date, the key will be included in the zone but will not be used to sign it. If not set, and if the -G option has not been used, the default is "now".

Sets the date on which the CDS and CDNSKEY records which match this key are to be published to the zone.

Sets the date on which the key is to be activated. After that date, the key will be included in the zone and used to sign it. If not set, and if the -G option has not been used, the default is "now".

Sets the date on which the key is to be revoked. After that date, the key will be flagged as revoked. It will be included in the zone and will be used to sign it.

Sets the date on which the key is to be retired. After that date, the key will still be included in the zone, but it will not be used to sign it.

Sets the date on which the key is to be deleted. After that date, the key will no longer be included in the zone. (It may remain in the key repository, however.)

Sets the date on which the CDS and CDNSKEY records which match this key are to be deleted.

Sets the prepublication interval for a key. If set, then the publication and activation dates must be separated by at least this much time. If the activation date is specified but the publication date isn't, then the publication date will default to this much time before the activation date; conversely, if the publication date is specified but activation date isn't, then activation will be set to this much time after publication.

If the key is being created as an explicit successor to another key, then the default prepublication interval is 30 days; otherwise it is zero.

As with date offsets, if the argument is followed by one of the suffixes 'y', 'mo', 'w', 'd', 'h', or 'mi', then the interval is measured in years, months, weeks, days, hours, or minutes, respectively. Without a suffix, the interval is measured in seconds.