Arrogant RBL list maintainers

Jack Bates jbates at
Wed Dec 16 09:32:37 CST 2009

Valdis.Kletnieks at wrote:
> When the hostname at that IP address is exactly one incremented character
> different than the preceding address, and one decremented character different
> than the following address, and that pattern holds across a /24, they're
> probably not mail servers.  Nobody has 256 'frzzmabs-1'..'frzzzmabs-256'
> servers in the same /24  for *anything* user-facing.

Mental note, don't setup 253 generic servers in the same /24 for dynamic 
allocation and usage by the load balancers and proxy servers.



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