Author: mailing Date: To: Exim users mailing list Subject: Re: [exim] [n@@b question] delete email if 550 error
> Kjetil wrote: > I've just been analysing our logs from a greylisting experiment, and it
> turns out quite a few servers will give up delivery after 3 hours. so
> if you can guarantee the server never will be down for more than 2
> hours, you won't lose mail. we don't keep postmasters on 24/7, so this
> could very well happen, although we hope it never will due to the
> redundancy in our setup. a backup MX isn't that hard to set up, anyway.
Thank you for this analysis.
A power failure (or whatever) could easily turn off servers for more than
3 hours (on week-ends, near midnight~).
> (I don't see why the OP doesn't simply turn on spam filtering on the
> backup MX.)
I did turn on a spam filtering feature, but as I said before: the primary
MX is a shared web hosting machine, which I can't control (thus I am not
able to know which anti-spam filters are set on the other side).