sendmail/saslauthd Domain Blocking

[Ernie Luzar]

Tim Daneliuk wrote:
> I block unwanted domains from sending mail to one of our servers by
> putting it on the reject list in /etc/mail/access.
> 
> I am seeing distributed brute force attempts to use that same
> server as a relay.  These are coming from a few domains.
> So far, these attempts have failed but I'd like to be proactive in
> preventing future such intrusions.
> 
> Is there an equivalent way to block entire domains and/or subdomains
> from ever even connecting to saslauthd?


Look at port dns2blackhole