Re: Uptick in spam

[Bill Cole]

On 1 Apr 2015, at 17:26, Amir Caspi wrote:

On Apr 1, 2015, at 3:03 PM, Kevin Miller  
wrote:


You can reject on RDNS (or lack thereof) in sendmail depending on the 
version.  Search for "require_rdns".


Thanks, I'll look into it.  Sadly I don't think I have time to 
manually whitelist misconfigured servers, since I suspect there are 
not a few of them... a lot of people fail to put rDNS entries on their 
mail servers (including my own $DAYJOB employer, who only fixed it 
once I complained).


That experience may bias your expectations. When I was handling spam 
control for a corporate system that had a million SMTP sessions per day  
and legit inbound mail in 5 digits per day with prominent public retail 
brand domains, our policy was to reject mail from IP's without valid 
rDNS. From 2004-2008 we had to whitelist *zero* sending systems and only 
had a handful of cases where we were the "bully" to get senders to fix 
their DNS. In the 7 years since I've been handling a much smaller 
corporate mail system of less significance to senders with the same 
policy, where we've seen no need to whitelist anyone and 2 cases where 
we know the policy has played some role in fixing senders' rDNS. 
However, it is a bit more common to have transient false positives due 
to DNS robustness issues (anything from connectivity problems to zone 
file typos) which are the price of any DNS-based filtering policy. The 
more DNS rules you enforce, the more ways DNS carelessness can be 
caught, and there's a richly diverse ecosystem of DNS carelessness.

Re: Irregular Test Reports in SA?

[Bill Cole]

On 31 Mar 2015, at 14:43, Kevin A. McGrail wrote:

But overall, it looks like lunarpages is exceeding some of the RBL 
limits which is immediately going to cause issues.


And to be blunt: that does qualify as "shoddy" in a commercial provider: 
amateurish & unethical. It's one thing for a hobbyist to accidentally 
hit the rate limits by using free shared resolvers like Google's or 
OpenDNS, it is an entirely different matter for a supposedly 
professional hosting operation to behave as leeches on services that 
honest businesses pay to keep running.

Re: TO_IN_SUBJ for username?

[Axb]

On 04/04/2015 07:46 PM, John Hardin wrote:


OK, tuned so it's less-specific about punctuation around the email
address in the Subject, and it attempts to parse an email address out of
the Subject if it appears prior to the To.

As AXB's masscheck host died leading to spam starvation in masschecks, I
don't know how soon the new version will be in updates.


got a dicey replacement... :)