Re: educating rDNS violators

From: Derek Schaible (dschaible_at_cssiinc.com)
Date: 08/28/04

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    To: Mark Reis <mcr2z@cs.virginia.edu>
Date: Sat, 28 Aug 2004 10:13:59 -0400

    On Wed, 2004-08-25 at 21:36, Mark Reis wrote:
    > A question for those who have implemented rDNS restrictions.
    >
    > In the case of a mail server with roaming users, how do you deal with
    > roaming users? A majority of our users travel to conferences and use
    > secure IMAP and SMTP to send their mail. Perhaps this is a
    > misconception, but I thought that some mail clients attempt to portray
    > themselves as a SMTP server relaying through the main mail server. If
    > we have users off traveling and having their email is blocked while they
    > were connected at a hotel with bad rDNS entries, I'd be getting ticked
    > off calls.
    >
    > Any suggestions?

    If you are providing a secure SMTP server that requires authentication
    for your road warriors, rDNS will have no effect on their ability to use
    it for out-bound mail. When they authenticate, they are added to the
    valid list of relay clients which will bypass these filters on the
    server. This is exactly how we provide smtp service for our traveling
    userbase.

    HTH 

    -- 
Derek Schaible <dschaible@cssiinc.com>
CSSI, Inc.

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