Am 16.01.2014 13:13, schrieb k...@jromiak.com.ar: > El 16/01/2014 08:52 a.m., James Day escribió: >> Hello Postfix User List, >> >> I'm struggling to work out why postfix is unable to forward >> this message when there is a valid MX record. > > It is *not* Postfix problem, but solely DNS problem. > > cbhc.uk.com uses 2 DNS servers: NS1.NSNOC.COM and NS2.NSNOC.COM > The problem is that NS2.NSNOC.COM responds to queries about > cbhc.uk.com, while NS1.NSNOC.COM doesn't. > >> The error states that there is no A record for the domain name >> (which is correct) but I would have thought Postfix should be >> looking for an MX record as well. > > Postfix searches for MX records 1st, then for A. But apparently > NS1.NSNOC.COM (bad luck!) was queried. and NS1.NSNOC.COM said that > there's not MX record, well, then Postfix tried to find A record, > as should, but A record doesn't exist too... (as thinks NS1.NSNOC.COM). > > Advise cbhc.uk.com to fix their DNS, NS1.NSNOC.COM and > NS2.NSNOC.COM *must* have the same data. Or you'll see > random troubles: sometimes mail works, sometimes doesn't, depends > on which of 2 DNS servers was queried. And remember about cached > and reused DNS data... > > Regards. >
after all dont use 8.8.8.8 in mailservers, you might fail with rbl lookups ( if you like to use that ), use some dns caching only software with your upstream dns server etc Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein
