Tim Sherburne mused: > > I would be nice to get a more coherent picture of the problems faced by some > folks on the list. I suspect that the problems can be traced back to sys > admins trying to stem the flood of spam they receive.
I rather doubt it. I receive my PDML mail on an account I have at panix.com They are scrupulously careful to ensure that every piece of email that enters their systems addressed to me ends up in my incoming mail file. I process the mail myself, using a .procmailrc that whitelists mail sent (or copied) to pentax-discuss as the first step, well before any spam-detecting software gets a chance to play with it. But, despite this, I'm not getting 100% of the messages. Panix take email delivery seriously. The only time they have filtered any mail recently was to junk one particularly agressive virus (which typically dumped 100MB or more of email into a mailbox; this blew out mail and disk quotas, causing valid email messages to be refused). Even that filtering only lasted a day or so. So, basically, if the list server (host24.websitesource.com?) opened an SMTP connection to mail.panix.com, and was told that any message addresed to me was successfully accepted, I'm absolutely sure that I would see it. The fact that I don't see all the messages suggests there may be other problems; what does the listserver do if it can't establish a connection? What if the connection gets established, but the handshake saying "I got that" never makes it back to the listserver? Or if the whole process just takes too long, and somebody times out? It's in the recovery from those sorts of problems that I believe the problem lies. We know that too many bounces, or other sorts of "mail undeliverable" problems, get you dropped from the list; we also know that when everything is running smoothly the messages _do_ get delivered. BUt what happens in between? Is there a particular path through the recovery from transient problems that can cause a message to be dropped? Nowadays it's unlikely to be a mail routing issue; most email is delivered point-to-point over a direct socket connection between the originating and destination mail servers. I really doubt that the problem lies in the TCP/IP socket protocols, or in the SMTP layer used to transfer the messages.
