[rbldnsd] TTLs and negative caching

[Jeff Chan]

On Tuesday, August 3, 2004, 6:30:31 AM, Michael Tokarev wrote:
> When tuning the TTLs, just choose numbers (by "try and see"
> method which is easiest to perform) that will generate
> acceptable load on nameservers while still having acceptable
> "response time" (false positives and negatives).  For a
> relatively static data (like SBL for example), a TTL of several
> hours (1..3, maybe even 6) seems to be acceptable.  I don't
> know how it applies to surbl data - that is, how much spam
> a spammer able to send using new domain while it will be
> expiring from ob.surbl.org caches.

Thanks much for your data, graphs and thoughts Michael and Jon.
It seems we are in somewhat uncharted territory, but we will do
some testing and see how things behave.  That should let us tune
our TTLs better.

Cheers,

Jeff C.
-- 
Jeff Chan
mailto:jeffc at surbl.org
http://www.surbl.org/