On Thu, 2008-02-21 at 13:48 +0100, Yves Goergen wrote: > I don't know anybody who really cares about that RFC postmaster account.
Well... there's a lot that can be said about this, but it's been said elsewhere so I'll leave that argument for another time. > My idea was, letting the initial SMTP sender wait a bit shouldn't be too > hard. So can't Exim just get the message and try to deliver it at once > instead of confirming it and delivering later? So when somebody passes > my server a message, an SMTP chain is established with the message going > forward and possible errors passed back. This way no bounce messages are > necessary. It can be problematic for long chains, but usually it's the > common way "sender" -> "[EMAIL PROTECTED]" -> "[EMAIL PROTECTED]" > and then it ends. Problematic in so many ways: you don't know how long the forward chain is, you don't know how many servers are involved, you don't know whether or not they will respond in a timely fashion, you don't know whether or not their network is reachable, you don't know if at some point in the chain someone is doing "accept-n-bounce", you don't know if somewhere down the line the message is being handled by a mailing list or other alias type "exploder" which generates tens, hundreds, thousands of messages... to list just a few. SMTP is a "best efforts", store-and-forward protocol, by definition. It isn't a real-time messaging system (which would have the safeguards you want built in). What you *can* do, which emulates the requirement you have, is to do call-forward verification using something like: require verify = recipient/callout,<callout options> but you should *only* use this if you know where the messages are going - do not use it for sender verification, or you'll quickly end up listed on some DNSBLs (again, another argument, another time, several other places). You will only be able to do this if the forwarding is done in a redirect router, and I recommend you read the docs to work out the best way for you. Graeme -- ## List details at http://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
