Re: [Exim] Delay 220 greeting to reduce spam?

On Jun 2, 2004, at 12:43, Andrew - Supernews wrote:

>>>>>> "Tor" == Tor Slettnes <tor@???> writes:
>
> Tor> Beware that this will interfere with sites that do callout
> Tor> verification (the timeout for which is 30 seconds by default).
>
> Timing out after 30 seconds is an explicit violation of the RFC.
> You lose, especially since mail.slett.net is sitting in the Comcast
> cesspit from which no sane person accepts mail connections without
> extremely stringent checks.

The server on which I do sender callout checks is actually a different
one: plain.knkco.com.

Exim's default timeout for callout checks is 30s; see section 38.22 in
spec.txt.

RFC2821 does not deal with callouts, and further uses the verb "SHOULD"
regarding the per-command timeout values (section 4.5.3.2). That
leaves ample room for interpretation as to appropriate timeout values
for sender verification.

-tor