[Mimedefang] Reject without PTR record

[Jim McCullars]

On Fri, 16 Jan 2004 dimon at intellinetinc.com wrote:

> What do you think folks, is that a good idea to reject emails from relays with
> no PTR record?

   It didn't work for me.  Funny you should bring this up now, I tried it
just a couple of days ago, adding a local ruleset to my sendmail.mc file
that would tempfail any emails that resulted in a temporary or permanent
DNS failure.  My idea was to watch it for a day or two and if it worked
out, change it to reject mail when there was a permanent DNS error.  That
way, any mail that was attempted during my test would hopefully get
re-sent if I decided to take it out.  As it turned out, I did take it out.
I looked at the sendmail log the next day and found that there is a lot of
screwed up DNS out there.  We were tempfailing legitimate higher-ed
related newsletters, as well as email from a large credit union in our
town (in fact, it is the largest credit union in Alabama).  I would still
like to do this one day, but I figured that this was not my ditch to die
in on this particular day :-)

   HTH...

Jim McCullars