No idea where else to ask this and get a real qualified answer but here. Not exactly pure centos question....but...
I am adding blacklists to my postfix smtpd settings. I have the inkling that after the first lookup for a domain or ip that my dns caches the result and I no longer bother the RBL or RHSBL list owners anymore in that instance.
Is that correct? I hate to waste their resources if it is not.
thanks, bob
On 04/04/2012 08:48 PM, Bob Hoffman wrote:
No idea where else to ask this and get a real qualified answer but here. Not exactly pure centos question....but...
I am adding blacklists to my postfix smtpd settings. I have the inkling that after the first lookup for a domain or ip that my dns caches the result and I no longer bother the RBL or RHSBL list owners anymore in that instance.
Is that correct? I hate to waste their resources if it is not.
thanks, bob
CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Not exactly. It is whatever TTL they return, though generally short for two reasons, they and you probably want it so that they can quickly remove entries from the blacklist once issues have been resolved.
They want to know how often you query the blacklist, because they want to charge a fee if you are a large site with high volume queries. I guess they need to fund their service somehow.
Nataraj
On 4/5/2012 12:52 AM, Nataraj wrote:
On 04/04/2012 08:48 PM, Bob Hoffman wrote:
No idea where else to ask this and get a real qualified answer but here. Not exactly pure centos question....but...
I am adding blacklists to my postfix smtpd settings. I have the inkling that after the first lookup for a domain or ip that my dns caches the result and I no longer bother the RBL or RHSBL list owners anymore in that instance.
Is that correct? I hate to waste their resources if it is not.
thanks, bob
CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Not exactly. It is whatever TTL they return, though generally short for two reasons, they and you probably want it so that they can quickly remove entries from the blacklist once issues have been resolved.
They want to know how often you query the blacklist, because they want to charge a fee if you are a large site with high volume queries. I guess they need to fund their service somehow.
Nataraj
CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
yea, I am already sending donations..well worth it. they 100,000 or more queries and then you can have access to the lists to download..though that ranges from 250 to 1000 a year, for each one....yikes. Still, well worth it if you have the cash and have a lot of users.
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Bob Hoffman -
Nataraj