-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Robert Blayzor Sent: August 21, 2002 10:53 PM To: 'Vivien M.'; nanog@nanog.org Subject: RE: IETF SMTP Working Group Proposal at smtpng.org
Running a mail server off a dynamically assigned dialup *CAN* work, but it really isn't the thing to do even if you put in a low TTL on the A record. Sure it works. But what about all the messages that will requeue on remote mail servers and depending on the remote queueing strategy of the remote mail server, it can take hours before mail could be re-attempted for delivery. A dynamically assigned MX box isn't really the best thing to do. If you want to do that then you should at least have a lower preference backup MX that is on 24/7 that will accept mail on your behalf, and when your server dynamic SMTP server comes online it can simply do an ETRN to requeue the mail on the backup MX.
Having one MX on a dynamic DNS mail server is just rude to remote mail servers that try to deliver mail. Why should my servers consume more resources to benefit your customers?
You're assuming that these people aren't permanently online. I expect most of our users (I hesitate to call them customers, simply because a lot of them haven't paid anything) are using 24/7 type connections. Certainly, running your own mail server and being online two hours a day is foolish. However, this has NOTHING to do with IP allocation. A friend, years ago, had a static IP dialup with an ISP that billed him for an X hour/month package, where I think X was 120 or so. He could have run a mail server that met your static IP standard of approval, and yet was (unless he wanted to pay extra) only online 1/6th of the time. Now, most of our users may not have static IPs, but they're most likely online 24/7 or close enough. Which of the two uses more resources on your servers? I'm willing to bet the static IP dialup person will, so there goes your argument. Running mail servers on non-permanent dialup connections is foolish, I'll grant you that any day, but that wasn't the point you were making. Your point was that mail servers on dynamic IPs (and you never answered my question on how you define dynamic) are bad, no matter the circumstances surrounding them, and that's just plain not true. Oh, and BTW, you're not benefiting our users by having your servers queue mail for our users. You're benefitting YOUR customers who presumably want to be able to send mail to our users, and who expect your servers to queue mail. Vivien -- Vivien M. vivienm@dyndns.org Assistant System Administrator Dynamic DNS Network Services http://www.dyndns.org/