On Wed, 27 Jul 2005, Brent Clark wrote:
> From: Brent Clark <bclark@???>
> To: exim <exim-users@???>
> Date: Wed, 27 Jul 2005 14:59:48 +0200
> Subject: [exim] interesting precheck
>
> I need to perform a tenet check on port 25 on a mail server, and I came
> across this:
>
> telnet mail.server.com 25
> Trying 1.2.3.4...
> Connected to mail.server.com.
> Escape character is '^]'.
> 220 mail.server.com ESMTP Exim 4.52 Wed, 27 Jul 2005 14:44:51 +0200
> mail.server.com
> 250 mail.server.com Hello mymail.mymailserver.com [10.11.12.13]
> mail from:<abc@???>
> 250 OK
> rcpt to xyz@???
> 500 unrecognized command
> rcpt to:<xyz@???>
> 550-Verification failed for <abc@???>
> 550-Called: 192.195.66.32
> 550-Sent: RCPT TO:<abc@???>
> 550-Response: 550 No such address
> 550 Sender verification callout failed.
>
> So basically it does mail from: lookup, before accepting the mail.
>
> Would anyone know how to achieve this.
>
> I bet its going to be something simple, but if someone would be
> so kind as to share how to do this, it would be great fully be
> appreciated.
It's using callout verification. Described in Section 39.31 of the
exim manual.
--
Dennis Davis, BUCS, University of Bath, Bath, BA2 7AY, UK
D.H.Davis@??? Phone: +44 1225 386101