On Tue, 29 Jul 2003, Alexander Sabourenkov wrote:
> ODHIAMBO G. Washington wrote:
> > Some clever? spammers are lurking around, for example I did receive
> > which looks like this:
> >
> >
>
> [...]
>
> > Now that IP is not in our netblock, and so I believe their helo should
> > have been blocked if I was bright enough. The problem is, they are
> > one step ahead of me.
> >
> > To keep off spammers, I'd like to do reverse lookups on envelope senders
> > and separately, to deny any envelope senders who say they are from our
> > domain (wananchi.com) but are sending from another IP range other than
> > our a.b.c.d/19 and e.f.g.h/25 *unless* they use ASMTP.
> >
> > Anyone already doing this???
>
> Beware of roaming/remote users using their own/other than your relays.
And watch out for mail from your domain sent to a remote address which
is then forwarded back to your domain.
--
Dr. Andrew C. Aitchison Computer Officer, DPMMS, Cambridge
A.C.Aitchison@??? http://www.dpmms.cam.ac.uk/~werdna
