Sendmail Sender Verification

[Mike Kercher]

I've got this working now and it appears to be doing a good job here as
well!  Thanks again for the link!

Mike


> -----Original Message-----
> From: MailScanner mailing list
> [mailto:MAILSCANNER at JISCMAIL.AC.UK] On Behalf Of Rose, Bobby
> Sent: Tuesday, March 30, 2004 8:35 AM
> To: MAILSCANNER at JISCMAIL.AC.UK
> Subject: Re: Sendmail Sender Verification
>
> I've been using milter-sender with sendmail for quite awhile
> to do this with good success.
>
> http://www.snert.com/Software/milter-sender/
>
> But it still won't stop a spammer or virus from using a valid
> email address but will stop bogus ones.  It also can do some
> other checks on the sending system.
>
> -----Original Message-----
> From: MailScanner mailing list
> [mailto:MAILSCANNER at JISCMAIL.AC.UK] On Behalf Of Mike Kercher
> Sent: Tuesday, March 30, 2004 1:28 AM
> To: MAILSCANNER at JISCMAIL.AC.UK
> Subject: OT: Sendmail Sender Verification
>
> I've been noticing more and more log entries from aol.com
> lately similar to the following:
>
> Mar 29 22:18:24 avwall sendmail[29603]: i2U4INJU029603:
> from=<>, size=3001, class=0, nrcpts=1,
> msgid=<200403300421.XAG19946 at rly-xk01.mx.aol.com>,
> proto=ESMTP, daemon=MTA, relay=omr-m11.mx.aol.com
> [64.12.138.23] Mar 29 22:18:30 avwall sendmail[29620]: i2U4INJU029603:
> to=<username at somedomain.com>, delay=00:00:07,
> xdelay=00:00:00, mailer=local, pri=123001, dsn=2.0.0, stat=Sent
>
> I assume that the omr- stands for Open Mail Relay or
> something of the sort and I also assume that it is verifying
> that the email address is deliverable prior to delivering an
> email from an address to the final AOL recipient.  I suspect
> they are doing something like this to combat their massive spam flow.
>
> Has anyone implemented anything like this with sendmail.  I
> know it would introduce additional network traffic, but might
> it be worth the trade-off?
> Thoughts?
>
> Mike
>