Juliano - USP - Using Greylist on DCC server

Vernon Schryver vjs@rhyolite.com
Thu Dec 4 23:03:55 UTC 2014

> From: Juliano Alves Guidini <jguidini@usp.br>

> We intend to change our greylist system on our MX. 
> I read the documentation about using greylist, but I still have a doubt. We have 3 DCC servers, for checksum messages, in this servers can I enable greylist? Or i need another DCC server, separated form my DCC cluster? 

The greylisting mechanism in the DCC clients (dccm and dccifd) uses
the same programs as a DCC server, but separate data and a separate
process that uses a different port number.

When the DCC greylisting code is used, it is common to run both a DCC
server and a greylist server on the same computer.  A single computer
with enough RAM should have no trouble running both a DCC server and
a greylist server for 10 million incoming mail messages per day.

Using the same computers for both DCC and greylist servers makes
it easy to back-up or load-share the greylist servers.
Use `cdcc "add dcc.example.com Greylist 32768 SECRET" to 
add the common DNS name dcc.example.com to the /var/dcc/map file.
Put lines like
    dcc1.example.com    12345 1000
    dcc2.example.com    12346 1000
    dcc3.example.com    12347 1000
in /var/dcc/grey_flod files to ensure that all of the greylist servers
have the same data.
You can use the same server-IDs for the DCC and greylist servers on a 
host because they are in different ID spaces.

Enable the greylist server and greylist checking by dccm or dccifd
in /var/dcc/dcc_conf.

Vernon Schryver    vjs@rhyolite.com

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