Barry Dwyer wrote: > > Would this reverse-DNS entry (apparently there for the convenience of > the ISP's reseller) be preventing some mail servers from forwarding to > ours? I noticed that your provider is a backup mailserver for you: dream:/usr/src # nslookup -type=MX nethan.com nethan.com preference = 500, mail exchanger = mail2.sohoskyway.net nethan.com preference = 1, mail exchanger = mail.nethan.com You may have the same problem I did at one time. Our provider was a backup mailer for us, and they didn't have their MS Exchange server setup to correctly route mail to me (I had to research the subject and TEACH them how to do this, btw, UGH...) - which would normally not be a problem since our Frame Relay is (supposed to be) up all the time - the backup mailer is _supposed_ to come into play only when the primary one is down. The normal way a mailer is supposed work is to try contacting the best preferrence mailserver, and if that doesn't work, the next preference, and so on... Well, MS Exchange doesn't do that - MS uses the get-mail-the-hell-out-as-fast-as-possible-and-screw-the-consquences approach: it opens a connection to _all_ mailers for a given domain, and hands off the mail to whichever mailer responds the fastest. So domains running MS Exchains servers were sending mail through my provider (because his connection to the outside is naturally much faster than mine), and the provider wasn't setup to relay for me, so the mail never got through. Some domains, running other mailers, got through just fine. And the really frustrating aspect was that even the domains that _were_ running MS Exchains would get mail through some of the time, when they happened to get directly into my server faster. It was horrible... Anyway, I dunno if this is your problem, but to check, try going to a machine outside your provider's domain, telnet to your provider's SMTP port, and try relaying mail through it into your domain. If his mailer refuses to relay for you, it might be the cause (it's a problem in any case). Eric
