Sleuth is a perl script designed for easy checking of DNS zones for
common errors and also for processing of secondary name service
requests. It was written after examination of at least a dozen of
utilities claiming to do this job, finding that all of them are either
unable to discover most zone bugs or too ugly to maintain. Sleuth also
lists the corresponding RFC references with most of its error messages,
so that the people upset with their zones being buggy can simply look
up what is exactly going wrong and how to fix it.