Re: Losing My SPAM Battle
- On 1 Apr 2008, at 08:54, Carlos Williams wrote:
I am running Postfix 2.3 as a corporate email server. I love running Postfix and don't want to switch to something else however SPAM is getting way out of control on my companies domain. Everyone is complaining about SPAM and I have to find a solution to this.
Does anyone have a complete guide or anything they recommend?Whilst this is a little more OpenBSD specific it worked fine for me:For the parts where you have to install the packages you can just use yum on CentOS but the configuration may be the same.Before all that have you turned on the RBL checks in Postfix, as well as all the other suggested anti-spam measures? Here's a good starting point:/etc/postfix/main.cf:...smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_non_fqdn_sender, reject_unlisted_sender, reject_unauth_destination, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_unauth_pipelining, reject_unknown_sender_domain, reject_rbl_client zen.spamhaus.org, reject_rbl_client list.dsbl.org, reject_rbl_client dul.dnsbl.sorbs.net,smtpd_helo_required = yesI have found dspam/ClamAV/Amavisd-new to be quite effective. I also use the OpenBSD dspam tarpit daemon as well. Very easy to setup, bounces about 75% of the spam straight off.Gaby.
- On Fri April 4 2008 20:02:50 Bill Cole wrote:
> >Although I don't intentionally use Comcast's nameservers, it's quiteYou are of course correct, and there was even a clue in my post: I
> >possible that they have transparently proxied DNS traffic.
> That would be a spectacularly evil thing to do.
> It seems within the realm of possibility (and far less evil) that
> Spamhaus has filtered all of Comcast's residential space from being
> able to query their servers, given the prevalence of zombies in that
fixed my issue by forwarding queries to my own remote servers. One of
these is through a VPN, but the others are reached using port 53, and
all are tested, answering my queries from there.
I am, however, familiar with at least one ISP that redirects DNS
traffic to its own servers: HughesNet home satellite. I bet it was a
matter of incompetence rather than malice; it's difficult to make a
laggy satellite connection work like ADSL or cable.
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