Hi Faris, if they uses a firewall with nat/pat maybe...
But this is not a generally problem, because many of our customers uses
Exchange and they uses our spamdyke as frontend.
I think they have to check their configuration of DNS/IIS (OWA) and so on.
Regards,
Ulrich
msp informations
technologie UG (haftungsbeschränkt)
--.--..-.-.-..-.--.--.-..-.-.--..--.--.-
Adresse Im Hofacker 21
D-79194 Gundelfingen
Telefon 0761 / 456 26 23 –0
Telefax 0761 / 456 26 23 –99
Mobil 0151 / 174 33 239
ICQ 21358399
E-Mail [email protected]
Internet http://www.msp-it.de/
Geschäftsführer Ulrich C. Manns
Eingetragen beim Amtsgericht Freiburg
HRB 704165
USt-ID-Nr. DE266213113
Am 12.02.2010 um 15:45 schrieb Faris Raouf:
> I had a very interesting conversation with a sysadmin who is in charge of
> mail server whose emails our Spamdyke servers are rejecting because their
> PTR has no corresponding A record (reject-unresolvable-rdns in
> spamdyke.conf).
>
> The sending server runs MS Exchange 2007, and apparently when they add an A
> record for their PTR, their webmail (whether accessed externally or
> internally) stops working.
>
> Does anybody have any experience of Exchange 2007? Does this make any sense?
> It doesn't to me. But I don't know enough about how Exchange works and how
> its webmail thing works either to make any real comment. My only guess is
> that it has something to do with the exchange server using a local private
> IP for the webmail server internally, and when this is effectively changed
> to a public IP it all falls down? I don't know why they can't just change
> the external DNS and leave the internal stuff alone, unless the Exchange
> server actually runs the external DNS too? Argh. It makes my head hurt just
> thinking about it.
>
> Obviously we can whitelist them - problem solved - but not everybody will do
> that for them and they are going to face some serious problems before long
> as more and more ISPs and mail servers come to reject on an unresolvable
> RDNS.
>
> And if it is a generic problem with Exchange then that's going to be a
> bigger problem for us and others.
>
> Faris.
>
>
>
>
>
>
>
>
> _______________________________________________
> spamdyke-users mailing list
> [email protected]
> http://www.spamdyke.org/mailman/listinfo/spamdyke-users
smime.p7s
Description: S/MIME cryptographic signature
_______________________________________________ spamdyke-users mailing list [email protected] http://www.spamdyke.org/mailman/listinfo/spamdyke-users
