On Mon, 05 Feb 2018 17:12:08 +0100 Benny Pedersen wrote: > Kevin A. McGrail skrev den 2018-02-05 16:53: > > > I don't think that will apply will it because it will be looking up > > something like 1.2.3.4.bb.barracuda.blah which isn't cached. > > the first qurry can make a qurry with very low ttl, so it would not > be cached, that means number 2 query still mkae dns query to that > zone :(
SA sends its DNS requests out early in rapid succession. The chances are that the local DNS cache would see the second request as a duplicate of a pending look-up. In that case caching is not needed. > > Anyway, we're debating a rule that's removed :) > lastexternal is still a mistake imho :=) lastexternal is correct, that's what RCVD_IN_BRBL_LASTEXT does. Making use of deep checks on lists containing dynamic addresses is risky, and likely to vary a lot between different mail flows. David's rules are not appropriate as a general replacement for RCVD_IN_BRBL_LASTEXT IMO.
