--On 13 August 2009 09:09:36 -0500 schmerold2@??? wrote:
> My Exim box is a front end filter for 10 domains using different mail
> servers (Exchange, cPanel, ClarkConnect & Groupwise). Dictionary attacks
> are taking their toll on the filter, so I would like to build a
> recipient list into the filter. Three of the domains are getting most of
> the spam. What I envision is a text file like this:
...
> Where the domains getting all the spam have a recipient list that is
> kept up to date, rest of the domains will accept and forward all clean
> mail. Any ideas?
Recipient callouts are by far the best way to do this, provided that your
recipient servers will reject mail that's destined for non-existant
accounts. They all should be configured like that. Even if some aren't,
you'll get better results by implementing recipient callouts where possible.
See section 40.42 of the documentation.
<
http://exim.org/exim-html-current/doc/html/spec_html/ch40.html#SECTcallver>
For domains that you can't do callouts on, there are various ways that you
can store user details locally, but first you should think about direct
queries on their user databases. For example, you could query an Active
Directory server for Exchange setups. Or other LDAP servers, for other
setups.
In the last resort, you might attempt to keep a local copy of your client's
user list, but be sure that your clients understand that their email
provisioning will become more difficult.
--
Ian Eiloart
IT Services, University of Sussex
01273-873148 x3148
For new support requests, see
http://www.sussex.ac.uk/its/help/
