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Re: Sendmail/Blacklists rejecting authenticated users

Subject: Re: Sendmail/Blacklists rejecting authenticated users
Date: Thu, 12 Jan 2006 03:10:49 +0000

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 <glynn@gclements.plus.com>

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