Author: Gedalya Date: To: exim-users Subject: Re: [exim] Idea: a retry which is more expansive,
uses the set of mx hosts
On 10/21/22 05:07, Ian Kelling via Exim-users wrote: > Sorry for the long email here. Let me know if anything isn't clear.
>
> In the spec, 32.4 sending to a.b.c.example is retried to another mx
> host. I've had yahoo return a temporary error which says roughly "don't
> email any of our mx hosts for a while".
Do they say that in response to RCPT TO:, making exim treat it as a per-address failure rather than a host failure? Otherwise I don't see why a retry rule for e.g. *.yahoodns.net. won't work.
I have indeed had situations where it would have been desirable to have exim process per-host retry rules even though the deferrals come after RCPT TO:.
> I'm imagining a new feature that would upon a delivery failure,
> record the recipient domain, and it's mx hosts, and then for any future
> delivery which is to that domain or if that domains mx list has any of
> previously failed hosts, then defer. Am I missing something?
> You might be able to implement that using the Events facility (ch. 61) with the help of an external database.
I'm still kind of fuzzy about the exact nature of the problem though.
