On Wed, Aug 15, 2007 at 05:28:10AM -0700, Alexander Perlis wrote:
> Instead, the upstream anti-spam RBLs are disappearing entirely (perhaps
> due to DDoS attack)
>
> So I ask again: does anyone know how to get Exim to keep track of
> timed-out DNS lookups against the local cache and not repeatedly retry
> such lookups on each SMTP conversation?
If I had the same problem, I'd probably consider something along the lines of
having Exim only attempt the RBL lookup if a flag is set somewhere (e.g. as
indicated by the existence of a file: say, /var/local/do-rbl). Then have some
external script periodically attempt an RBL lookup, and set the flag if it
succeeded, and clear the flag if it failed.
In other words, take the problem away from Exim.
Just a thought. Of course, you may already have, or be offered, a better
solution.
--
Dave Evans
Power Internet Limited, registered in England #03053650 at Norfolk House,
82 Saxon Gate West, Central Milton Keynes, Buckinghamshire, MK9 2DL.
For more information, see
http://www.powernet.co.uk/~davide/about-powernet
