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Re: Sendmail/Blacklists rejecting authenticated users

From: Glynn Clements (glynngclements.plus.com)
Date: Wed Jan 11 2006 - 21:10:49 CST


Michael Knox wrote:

> Quick question regarding dnsbl's... The other day I was in the
> Pittsburgh airport trying to send an email using their free wifi.
> Unsurprisingly this network's ip range is listed on a few of the
> blacklists. This resulted in my mail server rejecting my connection when
> I tried to send some emails. Does anyone know how I can configure
> sendmail/procmail to not check the IP addresses against the dnsbls for
> authenticated users?

The dnsbl feature is implemented in the check_relay ruleset, which is
called as soon as an inbound SMTP connection is made, before
authentication has occurred. If it rejects the connection, you won't
get a chance to authenticate.

You would need to re-implement the dnsbl feature in a later ruleset,
e.g. check_rcpt (this is the ruleset normally used to control
relaying).

If you need to access any of your services remotely, you may be better
off implementing a VPN.

--
Glynn Clements <glynngclements.plus.com>