Re: [exim] multi-stage fallback

Ian P. Christian wrote:
> Hi all,
>
> I'm trying to implement a multistage fallback as our current fallback
> server's queue is too big, and I think this is causing a few issues
> with things like greylisting (as it's not re-trying fast enough to hit
> some peoples greylist cache).
>
> I've had a bit of a google and I've not managed to find much on
> implementing such a system.
>
> Can anyone suggest a method?
>
> Thanks,
>
> Ian
>

Method depends on the 'why' of what you have now.

Are you not triggering queue runners often enough?

Is your queue full of icebergs in the form of undeliverables you should
have rejected up-front?

Are your retry rules altered from default?

Do you have reliable DNS resolvers available?

Are you saturating your bandwidth, or is it so dodgy that traffic cannot
reliably get out on each attempt?

Exim should be able to transit around 100,000 typical messages a day and
not stress typical hardware enough to kick the fans into high-speed.

A million per day - or letting spam 'too deep' into the machinery
before spitting it out, is another matter.

What are your numbers?

Bill