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Negative Caching of DNS Resolution Failures

Document Type Replaced Internet-Draft (dnsop WG)
Expired & archived
Authors Duane Wessels , William Carroll , Matthew Thomas
Last updated 2022-07-27 (Latest revision 2022-07-26)
Replaced by draft-ietf-dnsop-caching-resolution-failures
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Additional resources Mailing list discussion
Stream WG state Adopted by a WG
Document shepherd (None)
IESG IESG state Replaced by draft-ietf-dnsop-caching-resolution-failures
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


In the DNS, resolvers employ caching to reduce both latency for end users and load on authoritative name servers. The process of resolution may result in one of three types of responses: (1) a response containing the requested data; (2) a response indicating the requested data does not exist; or (3) a non-response due to a resolution failure in which the resolver does not receive any useful information regarding the data's existence. This document concerns itself only with the third type. RFC 2308 specifies requirements for DNS negative caching. There, caching of type (1) and (2) responses is mandatory and caching of type (3) responses is optional. This document updates RFC 2308 to require negative caching for DNS resolution failures.


Duane Wessels
William Carroll
Matthew Thomas

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)