Re: [nznog] Continued problems with xtra email

On 8/31/07, Joe Abley wrote:

On 29-Aug-2007, at 0431, Blair Harrison wrote:

...

On 8/29/07, Don Stokes wrote:

...

I've always advised that if a secondary MX host isn't going to do anything useful with incoming mail other than re-queue it for delivery, then just don't bother.

I'd have to wholeheartedly agree with that.

[A] --------- [B] \ / X / X / \ / [C]

[A], [B] and [C] are different networks on the Internet. I have a priority-0 MX installed at [A], and another one at [B]. The MX at [A] has a lower number in its RDATA than the one at [B] (i.e. the one at [B] is the backup).

Suppose some device at [C] tries to send me mail, and at the time it chooses to attempt delivery, there's a network problem which prevents traffic from getting through. It instead delivers to the backup MX at [B]. There is no network problem between [B] and [A], so mail is forwarded on straight away.

Please tell us that both [A] and [B] know all your users and domains (in other words: they reject e-mails for non existent users during the SMTP session). If not, I would say that [B] causes more problems for the world than it helps you because it probably generates zillion bounces per day ... Bojan