On Tuesday, July 27, 2004, 8:29:24 AM, Rob McEwen wrote:
RE: TTL/turnaround times for SURBL
In particular, Jeff noted that Outblaze updates their data very fast in response to fast analysis of their spam-trap data. But the OutBlaze feed at SURBL get updated every six hours? Doesn't that defeat the purpose. Would it be possible to speed up the ob.surbl.org refresh so that we can reap more benefits from their quick responsiveness?
I think that would be done by lowering the TTL. The time to live appears to indicated to DNS how quickly new information should be served up. Do any DNS gurus know if that's correct? In other words if we lower the TTLs on our zone files should we expect new entries to be visible sooner.
Also, it was mentioned that the sc.surbl.org data updates every ten minutes? Is there really substantial new or different data in this feed to justify this? (in other words, is there a system where very, very new data causes quick updates to sc.surbl.org)
Yes, sc.surbl.org gets new data sometimes as often as every two minutes. The SpamCop data is close to a real time feed.
Finally, has any progress been made speeding up the refresh times for multi.surbl.org?
It's certainly something that can be done rather easily but I'd like to get some feedback about the impact on our nameservers as a result. Do shorter TTLs mean more DNS traffic? Does it cause positive caches to expire sooner and therefore cause more querying of authoritative name servers?
Jeff C.