SPF DNS Error / R_SPF_DNSFAIL

[Bernardo Reino]

On Mon, 19 Dec 2022, Carlos Mogas da Silva wrote:

> Hi list.
>
> My incoming messages are getting R_SPF_DNSFAIL and an error on the 
> Authentication-Results header:
>
> spf=temperror
> (mail01.r3pek.org: error in processing during lookup of
> no-reply at cttexpresso.pt: DNS error)
>
> I see the DNS request on my DNS server and a "working" reply going out. What 
> can cause this error and/or how can I debug it?

How (which program) is the SPF check being done?

Dovecot doesn't do that (AFAIK anyway), so maybe you want to check which program 
(e.g. a postfix milter, such as rspamd) is doing that and check the logs of that 
program to see what went wrong.

But I'm 99.9% sure this has nothing to do with dovecot :)

Cheers,
Bernardo