[vox-tech] Anyone running a mail server on a dynamic IP?

[Brian Lavender]

On Wed, Jun 16, 2004 at 10:15:18PM -0700, Rod Roark wrote:
> Seems like most of the spam that I (and thus LUGOD) are not
> successfully filtering out these days is from dynamic IPs -
> dialup, cable modem, and dynamic DSL.
> 
> So I'm wondering if it's reasonable to refuse mail from
> servers that connect directly from a dynamic IP.  Is anyone
> here running such a server?  And if you are, are you finding
> that many sites are refusing your mail?
> 
> Please reply off-list unless you think that what you have to
> say is of general interest.  Also if you're not sure if your
> IP is considered dynamic, you can check it at
> "http://www.dnsbl.us.sorbs.net/cgi-bin/lookup?IP=".

Well, consider this. You have a valid send who is sending you email from
a dynamic IP. You would want to receive that email, right?!!

The answer lies in SpamAssassin. I believe it scores on this blacklist.
SpamAssassin has been 100% effective with over 300+ spams in the last
24+ hours! The next question is, do you want to process this email? I
don't. That's why I have been testing SA-Exim. If it gets flagrant
spam from an IP, it can put in a temporary reject. Or, it can put in a
permanent reject. Or....  if it's really bad spam, you can teergrub it.
Or, say I do have a sender who does use mail server on a dynamic IP. I
can whitelist him and get his email.

I am doing a talk on integrating SpamAssassin at the SMTP layer. The
implementation is SA-Exim. http://www.saclug.org/

brian


-- 
Brian Lavender
http://www.brie.com/brian/