Should env_To checksums work with greylisting?

Vernon Schryver
Mon Dec 8 02:19:31 UTC 2003

> From: Gary Mills <mills@cc.UManitoba.CA>

> Today, I enabled greylisting on our mail servers.  It seems to work
> very nicely.  The reduction in spam is dramatic.

That's good to hear.

> One thing that I noticed was mail to my spam trap addresses has also
> been greatly reduced.  These addresses are all whitelisted by env_To
> in the dccm client whitelist.  I'm wondering if mail to those addresses
> is now being embargoed by DCC?  My spam traps issue automatic complaints
> to the sender's ISP, so I'l like them to continue to work.  Is this no
> longer possible?

Dccm consults the local whitelist first, the greylist system second,
and DCC servers third.  The first unambiguous white/black or accept/reject
answer obtained rules and aborts later consultations (with some
complications to allow initial, greylisted transmissions to be reported
to and counted by the DCC).

If your traps are whitelisted by the local or dccm whiteclnt files,
then greylisting does not apply to listed addresses or other listed

Wasn't UManitoba.CA using the deprecated server-side DCC whitelists
because of limitations in the sizes of IP address CIDR blocks for
client-side whitelists?  I kludged large CIDR blocks into dccm whitelists
in version 1.2.15.

Vernon Schryver

P.S.  I recently spent most of a week switching my main system from
  BSD/OS 4.2 to FreeBSD 4.9.  Escaping the BSDI mmap() and other bugs
  is great, but you may have seen problems with the DCC mailing lists.
  Please let me know if I didn't fix them all.

More information about the DCC mailing list

Contact by mail or use the form.