Rick DeNatale wrote:
Intelligent mail systems (like Gmail, presumably) will send your message to one of a dozen or more "outgoing" smtp relays. That message then gets queued up on that machine for delivery, and that one machine is responsible for the final delivery of that message. Each delivery attempt will come from that one machine, with it's IP address. This is by far the easiest way to scale this solution, as it only requires a lot of boxes, and one round-robin DNS entry.For those of us who use things like gmail, which no doubt use email server farms, it might take a while for all of those ip addresses to get greylisted.
In other words the "you" in "the first time you send a message to the list." is a bit fuzzy in these cases.
At least it looks like the mail will get a soft bounce, and not a hard bounce.
Less intelligent systems may do as you fear, and have one large queue, and any of a dozen machines can pull out the message and send it. Not only is this method more difficult to implement, it's much messier and has a central point of failure (that big central queue). As the popularity of greylisting spreads, people will stop doing brain-dead things like that. :) Most of them already have. In the very unlikely case that turns out to be a problem, we have the flexibility to add exceptions to the grey-listing, based on IP address or IP address range, which allows us to work around the stupidity of others.
Aaron S. Joyner -- TriLUG mailing list : http://www.trilug.org/mailman/listinfo/trilug TriLUG Organizational FAQ : http://trilug.org/faq/ TriLUG Member Services FAQ : http://members.trilug.org/services_faq/ TriLUG PGP Keyring : http://trilug.org/~chrish/trilug.asc
