Hi, On 08/03/2019 21:29, Dave Lawrence wrote:
> Huh, My understanding from a hallway conversation with Benno was that > the immediate response is only sent for names that would have been > subject to pre-fetching, such that the immediate response in this case > is sufficiently covered under the guidance of a recent attempt being > made. If that is not the case, and you can get stale answers from > Unbound even without a recent refresh attempt, then I personally think > that is an error in Unbound and not this document. The current implementation of serve stale in Unbound is closely related with the pre-fetching process. It works well for most cases, that is names that are frequently queried for, so the pre-fetch assures for fresh and correct entries in the cache. For names with relative short TTLs and that are not frequently queried for (i.e. less frequent than covered by the TTL), the entry from the cache is stale and only after serving the reply, a pre-fetch (resolve) is initiated to update/re-fresh the entry in the cache. We acknowledge this behavior is not optimal in some situations and will reimplement a part of the re-fresh strategy of cache entries. -- Benno -- Benno J. Overeinder NLnet Labs https://www.nlnetlabs.nl/ _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
