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Re: Sendmail/Blacklists rejecting authenticated users

Subject: Re: Sendmail/Blacklists rejecting authenticated users
Date: Wed, 11 Jan 2006 14:35:41 -0700
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? I have already done a fair amount of googling but haven't come up with anything workable, nor can I think of a good way to test (since I don't have access to a blacklisted network).
Thanks,
Mike

Several options:

1) Use the submission port (587) and configure it to allow authenticated users only (no other restrictions)

2) Setup postfix/etc ocrrectly so that authenticated use is allowed even if the IP is on DNSRBL (i.e. the order of smtpd_recipient_restrictions or whatever you are using matters).

3) Stop using DNSRBL (I find OpenBSD's spamd does a MUCH better job in any event, it's catching about 90% of my inbound spam and pretty much all the viruses with no false positives) however by protecting port 25 to all your mail servers you will need to setup something for sending email (either submission port or a mail relay with user authentication).

-Kurt

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