Re: Defensive liveness testing of DNSBLs

[Arnt Gulbrandsen]

I wrote:
2. Write something to run daily or weekly, parse the postfix 
logs, and alert you if the block rate for any RBL drops to zero.

Or, in light of Wietse's response, modify the lookup code. If the number of 
consecutive OK responses grows implausibly large, check 127.0.0.{1,2} and 
conditionally disable use of that RBL for a day or a week.

Arnt