NAMEs consist of an ordered sequence of one or more NAMEs are specific to a CLASS as described NAME is an owner name, i.e., the name of the node to which this DNS Resource RecordsĪll RRs have the same top level format shown in the figure below RFC 2929 DNS IANA Considerations September 2000 3. Since it is important that RCODEs be understood for interoperability,Īssignment of new RCODE listed above as "available for assignment" See table below.ģ NXDomain Non-Existent Domain Ħ YXDomain Name Exists when it should not ħ YXRRSet RR Set Exists when it should not Ĩ NXRRSet RR Set that should exist does not ĩ NotAuth Server Not Authoritative for zone ġ0 NotZone Name not contained in zone ġ6 BADSIG TSIG Signature Failure ġ8 BADTIME Signature out of time window Ģ0 BADNAME Duplicate key name Ģ1 BADALG Algorithm not supported
#Rcode servfail code#
RCODE field and the TSIG and TKEY RRs have a 16 bit RCODE field.Įrror codes appearing in the DNS header and in these three RR typesĪll refer to the same error code space with the single exception ofĮrror code 16 which has a different meaning in the OPT RR from its The OPT RR provides an eight bit extension resulting in a 12 bit However, RCODEs canĪppear not only at the top level of a DNS response but also inside RCODE, or response/error code are available. It would appear from the DNS header above that only four bits of RFC 2929 DNS IANA Considerations September 2000 2.3 RCODE Assignment New OpCode assignments require an IETF Standards Action.Ĭurrently DNS OpCodes are assigned as follows: It is believed that current DNSĪssigning a meaning to the Z bit requires an IETF Standards Action. On in a query meant that only a response from the primary server forĪ zone is acceptable. There have been ancient DNS implementations for which the Z bit being
#Rcode servfail update#
Prerequisite (PRCOUNT), update (UPCOUNT), and additional information Update but are instead the counts for the zone (ZOCOUNT), These fields have the same structure and data type for The unsigned fields query count (QDCOUNT), answer count (ANCOUNT),Īuthority count (NSCOUNT), and additional information count (ARCOUNT)Įxpress the number of records in each section for all opcodes except Such meanings may only be assigned by an IETF
Use a "query" bit with a different meaning in a response or to defineĪ query meaning for a "response" bit is dangerous given existing Of the response header without clearing bits. Many DNS implementations copy the query header as the initial value Only in queries or only in responses, depending on the bit. The AA, TC, RD, RA, AD, and CD bits are each theoretically meaningful The QR bit indicates whether the header is for a query or a response. RFC 2929 DNS IANA Considerations September 2000 The ID field identifies the query and is echoed in the response soĮastlake, et al. |QR| Opcode |AA|TC|RD|RA| Z|AD|CD| RCODE | The header for DNS queries and responses contains field/bits in theįollowing diagram taken from : "IETF Standards Action", "IETF Consensus", "Specification Required",Īnd "Private Use" are as defined in. IANA currently maintains a web page of DNS parameters. Query/response opcode for such considerations if they have been See the specific RFC defining that RR type or There may be additional IANAĬonsiderations that apply to only a particular RR type or
Parameter assignment considerations applying across DNS query and This document covers, either directly or by reference, general IANA This data is structured into CLASSes and zones which can be Hierarchical databases which hierarchically store "resource records" The Domain Name System (DNS) provides replicated distributed secure
RFC 2929 DNS IANA Considerations September 2000 1. (DNS) classes, Resource Record (RR) types, operation codes, errorġ. Internet Assigned Number Authority (IANA) parameter assignmentĬonsiderations are given for the allocation of Domain Name System Distribution of this memo is unlimited.Ĭopyright (C) The Internet Society (2000). Internet Community, and requests discussion and suggestions for This document specifies an Internet Best Current Practices for the RFC 2929: Domain Name System (DNS) IANA Considerations ĭomain Name System (DNS) IANA Considerations
0 kommentar(er)
