Focus on Linux
Sendmail/Blacklists rejecting authenticated users Jan 10 2006 06:58PM
Michael Knox (mikeknox lcse umn edu) (5 replies)
Re: Sendmail/Blacklists rejecting authenticated users Jan 12 2006 09:48PM
Łukasz Kwiek (woo suntar pl)
Re: Sendmail/Blacklists rejecting authenticated users Jan 12 2006 03:10AM
Glynn Clements (glynn gclements plus com)
Re: Sendmail/Blacklists rejecting authenticated users Jan 11 2006 11:59PM
Robert BARABAS (dc ktk bme hu)
Re: Sendmail/Blacklists rejecting authenticated users Jan 11 2006 09:47PM
Scott Gifford (sgifford suspectclass com) (1 replies)
Re: Sendmail/Blacklists rejecting authenticated users Jan 12 2006 09:42PM
Bill Weiss houdini+focus-linux (at) clanspum (dot) net [email concealed] (houdini+focus-linux clanspum net) (1 replies)
Re: Sendmail/Blacklists rejecting authenticated users Jan 16 2006 01:18AM
Scott Gifford (sgifford suspectclass com)
Re: Sendmail/Blacklists rejecting authenticated users Jan 11 2006 09:35PM
Kurt Seifried (bt seifried org)
> 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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