[Info-vax] Anything wrong with this anti-spam measure?

[Neil Rieck]

On Oct 19, 4:44 am, hel... at astro.multiCLOTHESvax.de (Phillip Helbig---
remove CLOTHES to reply) wrote:
> Running an SMTP server at home, I get a lot of SMTP connections.  Most
> are spam.  I get about one connection per second.  Using the
> spamhaus.org RBL and setting Symbiont-Checks-Deliverability: to FALSE in
> SMTP.CONFIG gets rid of most of it before it even gets to VMS MAIL.  
> Most of the stuff is from addresses in the RBL or to a non-existent user
> or both.
>
> Unfortunately, I am still at TCPIP V5.4, so an email to a non-existent
> user which is NOT a syntactically correct username gets through
> (assuming it doesn't come from an RBL address).  I hope to upgrade VMS
> and TCPIP by the end of the year.  IIRC, this has been fixed in a newer
> TCPIP.  Right?
>
> Until recently, this was not a problem, but for a few weeks now I have
> been getting A LOT of spam to three addresses.  This is a pain, and the
> rejection messages probably generate backscatter spam.  Thus, I did the
> following (IIRC, this was originally suggested here by JF): create an
> empty file called NL.DIS in TCPIP$SMTP_COMMON, then do this:
>
>    MAIL> SET FORWARD/USER=<non-existent user> SMTP%"N... at multivax.de"
>
> Although the mail does get as far as VMS MAIL and thus consumes more
> resources, otherwise it seems to work OK, i.e. it disappears silently
> and has no side effects.  Can anyone think of any potential problems
> with this approach?
>
> (By the way, I recommend defining TCPIP$SMTP_COMMON to be a search list
> containing the default SYS$SPECIFIC:[TCPIP$SMTP] as well as a
> user-defined directory for use with all nodes in the cluster.  .DIS
> files and so on can go into this common directory.)

Not sure about HP's stack, but on a system running TCPware there is a
designated "post master" which receives all mail with no account. For
years now this has been defined as NEIL. At the beginning of this year
I decided to do the following:

1) Create a bogus account name that no one could ever guess
2) Install DELIVER from the OpenVMS freeware disc
4) In the bogus account, I created a file named MAIL.DELIVERY which
contains rules to ignore (throw away) the biggest SPAM sources, SPAM
destinations, or SPAM subjects. All others are transferred to account
NEIL. With about 30 lines I throw away more than 90% of the SPAM
hitting my system

http://www3.sympatico.ca/n.rieck/docs/openvms_notes_deliver.html

Neil Rieck
Kitchener / Waterloo / Cambridge,
Ontario, Canada.
http://www3.sympatico.ca/n.rieck/OpenVMS.html