duplicate suppression, sieve, loops, redirect and lost email

[Lawrence Greenfield]

   Date: Fri, 30 Aug 2002 11:37:53 -0400
   From: Ken Murchison <ken at oceana.com>
[...]
   > I believe that (in an ideal world) Cyrus should tolerate a redirect
   > "myself at example.com" and treat it as a keep.

   Should we treat it as a keep, or fail with an appropriate warning?  If
   we do a keep without complaining, aren't we just promoting bad sieve
   behavior?

I think it should do a keep.  that said...

   BTW, has this issue ever been discussed on mta-filters?

Not to my knowledge.

[...]
   A (overly?) simple approach is to take the unqualified envelope rcpt
   along with recursively broader-scoped pieces of the server hostname and
   compare them to the redirect address, ie:

   leg at cyrus.andrew.cmu.edu
   leg at andrew.cmu.edu
   leg at cmu.edu

   The problem is that these might be different users in some
   installations.  Another problem is aliases.  What if I redirect to
   arm at andrew.cmu.edu and this is an aliases to leg at ...?

It's also very possible for leg at ... to redirect to different
mailboxes. (Maybe my real primary account is leg at cs.cmu.edu, which
uses their own Cyrus server.)

   I also haven't thought about how these solutions might work with
   virtdomains.

   I agree that it would be nice to to some behind the scenese magic, but I
   still think that preventing the problem (ie, don't do that) is far
   easier than trying to fix it.

I don't see any reasonable fix for now, so we should just file a bug
and hope for enlightenment down the road.

Larry