On Sat, Jul 24, 2021, at 09:14, Xavier Beaudouin via mailop wrote: > Hello, > > >> But it seems they never trys the best preference first..... > >> > > > > Are you greylisting or running pregreet tests on your MXes? > > > > Here's what I think is happening. MS first tries the priority 10 MX, > > and postscreen (or such) issues some tests that delay the transaction, > > so then MS tries the next (next, next...) priority MX and eventually > > ends up on your highest priority MX. > > I use greylisting... BUT... there is not log trace from microsoft servers on > the 10 MX... so they didn't bother about greylisting... > Maybe they had some issue... I changed the priority to 50... let's see > if there is something different...
One consideration is that Microsoft seems to cache connection failures, possibly quite aggressively, so you shouldn't expect to see much further traffic once your primary MX gets on the list. I do similar on my own server, although not as aggressively, and I've had a few cases where someone was yelling at my postmaster@ for hitting their lower priority MX when their primary MX was "working perfectly" and it turned out the primary MX was definitely not. _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
