[Mimedefang] Verifying mailbox...

[Matthew.van.Eerde at hbinc.com]

> From: Ashley M. Kirchner [mailto:ashley at pcraft.com]
> So, my question now is, from within mimedefang, is there some way I 
> can have it validate a recipient's address PRIOR to attempting 
> delivery?  Like somehow contacting the spool and see if that user 
> exists, and if not simply bounce the message before it even gets onto 
> our network.
> 

Yup.  Two ways, in fact.

I) use md_check_against_smtp_server to validate the recipient address.
and/or
II) build a sendmail "access" file based on directory listings from the
downstream mail servers.  These would look like

joe at sitea.example.org OK (or RELAY)
ethel at sitea.example.org OK (or RELAY)
...
@sitea.example.org REJECT (no unknown users @sitea.example.org!)

jane at siteb.example.org OK (or RELAY)
fred at siteb.example.org OK (or RELAY)
...
@siteb.example.org REJECT

postmaster at example.org OK (or RELAY)
...
@example.org REJECT

II) has nothing to do with MIMEDefang and is a purely sendmail technique.

Depending on internal connection speed vs. email longevity one or the other
approach might be better for your particular network.

Matthew.van.Eerde at hbinc.com                      805.964.4554 x902
Hispanic Business Inc./HireDiversity.com         Software Engineer
perl -e"map{y/a-z/l-za-k/;print}shift" "Jjhi pcdiwtg Ptga wprztg,"