On Fri, Jun 14, 2013 at 02:27:50PM +0000, Manson, John <John.Manson at mail.house.gov> wrote a message of 138 lines which said: > We are running Bind 9.9.2 and would like to invoke the rate-limit > option but named says 'unknown option'. RRL (Response Rate Limiting) is an unofficial patch. You'll have to patch the source first.