Mark Andrews <[email protected]> wrote: > In message <[email protected]>, "John Levine" writes: > > > > >You could apply the technique to any signed zone where you are not > > >worried about not having instant visibility after adding a new name > > >to the zone. > > > > I don't understand this. If I ask for foo.example and get NXDOMAIN, > > and 10 ms later you add a record at foo.example, my negative answer is > > cached for your SOA TTL is. > > For 99.999999999% of names you don't look them up unless you have > a priori knowledge that the name exist.
Having done this myself, I think there are several situations in which it is common to look up a name shortly before adding it to a zone. e.g. you expect a name to exist, whoops, fix the omission, then have to wait a TTL. Or you are trying to come up with a domain name that hasn't already been registered and you forget to send the query to the TLD servers instead of the local cache. Can be quite annoying if the TTL is long. Even so, I like aggressive negative cacheing. Tony. -- f.anthony.n.finch <[email protected]> http://dotat.at/ Forties, Cromarty, Forth, Tyne, Dogger, Fisher, German Bight, Humber: South, veering west, 6 to gale 8, occasionally severe gale 9 in Forties and Fisher, decreasing 4 or 5 for a time. Moderate or rough, occasionally very rough. Occasional rain or snow, fog patches. Moderate or poor, occasionally very poor. _______________________________________________ DNSOP mailing list [email protected] https://www.ietf.org/mailman/listinfo/dnsop
