On Tue, 2021-10-05 at 11:04 -0700, Paul Vixie wrote: > was cache miss deduplication by q-tuple ever standardized? it is a nec'y part > of kaminsky resistance and so ought to be part of whatever BCP corpus comes > about. pending upstream query behaviour would be an expansion on cache miss > dedup by q-tuple, such that a rising tide of timeouts would yield > probabilistic prediction of servfail for cache misses aimed at the affected > <zone,auth>.
https://datatracker.ietf.org/doc/html/rfc5452#section-5 describes the problem, without prescribing a solution. PowerDNS Recursor performs 'query chaining' to prevent those duplicate queries. It is not described in the docs outside of this small phrase: https://doc.powerdns.com/recursor/metrics.html?highlight=chaining#chain-resends Kind regards, -- Peter van Dijk PowerDNS.COM BV - https://www.powerdns.com/ _______________________________________________ dns-operations mailing list [email protected] https://lists.dns-oarc.net/mailman/listinfo/dns-operations
