I can't speak for anyone else, but those two filters have been very good 
for my users.  On a typical day, 30-60% of all connections to my server 
are blocked with DENIED_IP_IN_CC_RDNS.  Another 5-20% are blocked by 
DENIED_IP_IN_RDNS.  I've had to whitelist a few IP addresses with bad 
rDNS names but that's been very rare so far (less than 5 total).

However, servers with larger user populations and more international 
correspondence might have different experiences.

-- Sam Clippinger

Marcin Orlowski wrote:
> Hi,
>
> Anyone by any chance did sort of research if DENIED_IP_IN_*_RDNS helps
> his users or causes more problems? I formerly thought that this is
> more helpful, as IP in RDNS is most likely appear for home dsls, dialups
> and other stuff not supposed to run smtp server i shall trust, and if
> it's my users mail netline, then they shall authenticate while talkign 
> to me anyway. But now I see that some telecoms offer dsls with static 
> IPs (contrary to dyniamic one, rotated 24hs, that is addressed to home 
> users) which is primarily used by companies, and therefore it's less 
> likely for them to be spam source (due to botnes, zombies etc). I even 
> saw a data center which named their rack hosts that way. I therefore 
> think that it might be extremely useful to try to build a kind of 
> database of providers who one may consider whitelisting even, they would 
> otherwise fall into IP_IN_RDNS or IP_IN_CC_RDNS trap. Any thoughts?
>
> Marcin
> _______________________________________________
> spamdyke-users mailing list
> [email protected]
> http://www.spamdyke.org/mailman/listinfo/spamdyke-users
>   
_______________________________________________
spamdyke-users mailing list
[email protected]
http://www.spamdyke.org/mailman/listinfo/spamdyke-users

Reply via email to