dhcpd.conf

...
...
authoritative;
ddns-update-style interim;
key dhcpupdate {
        algorithm hmac-md5;
        secret "fi1HKwB0RqSmyV4WGe4DrQ==";
}
...
zone domain.local {
        primary 10.100.10.5;
        key dhcpupdate;
}
zone 10.100.10.in-addr.arpa {
	key dhcpupdate;
}
...
group {

	option domain-name-servers 10.100.10.5;
	option domain-name "some.domain.local";

	ddns-domainname "home";

	host db1.some.domain.local {
		hardware ethernet 55:55:55:55:11:5b;
                option host-name = "db1.some.domain.local";
		fixed-address 10.100.10.10;
		ddns-hostname "db1";
	}
}