A DNS Rcode describes the result of a DNS request. If EDNS is not in use, then the rcode is encoded solely in the DNS header. If EDNS is in use, then the rcode is encoded using bits form both the header and the EDNS OPT RR.
dns.rcode.NOERROR
dns.rcode.FORMERR
dns.rcode.SERVFAIL
dns.rcode.NXDOMAIN
dns.rcode.NOTIMP
dns.rcode.REFUSED
dns.rcode.YXDOMAIN
dns.rcode.YXRRSET
dns.rcode.NXRRSET
dns.rcode.NOTAUTH
dns.rcode.NOTZONE
dns.rcode.BADVERS
dns.rcode.from_text
dns.rcode.to_text
dns.rcode.from_flags
dns.rcode.to_flags