Re: [swinog] Nice to know for ISPs: Exchange 2003 SP2 Greylisting bug
Martin Blapp wrote: We just had a case where we missed some mails from a vendor, and those mails now have arrived with three month delay. After some investigation we found the reason for the delay: the vendor is using Exchange 2003 SP2, which has a known, still unfixed bug. It causes outbound mail to domains that implement greylisting to be jailed in a black hole until the SMTP service is restarted. I can't believe that even Exchange would be unable to do a retry - there are plenty of situations where a server might return a temporary 45x error. -- /Per Jessen, Zürich ___ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
Re: [swinog] Nice to know for ISPs: Exchange 2003 SP2 Greylisting bug
Hi, I can't believe that even Exchange would be unable to do a retry - there are plenty of situations where a server might return a temporary 45x error. The error isn't easy to reproduce. It seems that some conditions are necessary. It might be a race condition. Exchange never managed it to 100% comply with the existing RFCs. That hasn't changed at all. And it still looks like Microsoft doesn't handle bugs seriously if only a small to average userbase is affected. This bug has only made it up to the second level support of Microsoft. -- Martin ___ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
Re: [swinog] Nice to know for ISPs: Exchange 2003 SP2 Greylisting bug
Am Donnerstag, den 21.06.2007, 09:49 +0200 schrieb Martin Blapp: Exchange never managed it to 100% comply with the existing RFCs. That hasn't changed at all. And it still looks like Microsoft doesn't handle bugs seriously if only a small to average userbase is affected. This bug has only made it up to the second level support of Microsoft. I think, proposal #4 should work for all ;) If you have crappy software, remove it. -- Mit freundlichen Gruessen Andre Timmermann Nine Internet Solutions AG, nine.ch Letzigraben 77, CH-8003 Zuerich Tel +41 44 481 16 42, Fax +41 44 481 16 43 ___ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
Re: [swinog] Nice to know for ISPs: Exchange 2003 SP2 Greylisting bug
Martin Blapp wrote: Hi, I can't believe that even Exchange would be unable to do a retry - there are plenty of situations where a server might return a temporary 45x error. The error isn't easy to reproduce. It seems that some conditions are necessary. It might be a race condition. Exchange never managed it to 100% comply with the existing RFCs. That I can easily believe, but it just seems incredible that it wouldn't be able to deal with a retry. Which is why I doubt it should somehow be related to greylisting. -- /Per Jessen, Zürich ___ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
Re: [swinog] Nice to know for ISPs: Exchange 2003 SP2 Greylisting bug
4. remove MS Exchange as its unable to fulfill internet capabilities. or 5. use a smarthost instead of connecting MS Exchange directly to the internet :-) -- Martin ___ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
Re: [swinog] Nice to know for ISPs: Exchange 2003 SP2 Greylisting bug
WORKAROUNDS === 1. Write a script to restart the SMTP service at least once a day. 2. Modify the registry on the sender Exchange server, to change the Glitch Retry key. 3. Clarify that there is no 3rd party AV software in the environment which could be causing the issue. 4. remove MS Exchange as its unable to fulfill internet capabilities. smime.p7s Description: S/MIME cryptographic signature ___ swinog mailing list swinog@lists.swinog.ch http://lists.swinog.ch/cgi-bin/mailman/listinfo/swinog
