A recent thread about an RHSBL just got me thinking. There seems little point in lots of Bytemark customers running their own mirror zones of all the same RBLs. Would it not be much more sensible and efficient if Bytemark were to make all the most common zones available on their resolvers instead? Just one copy of each zone required instead of many and each customer gets the local lookup for zero effort.
Then I thought, “maybe they do this already”, because I can’t think of an easy way to tell if the result returned by the Bytemark resolvers is authoritative-local, authoritative-recursive or cached.
So, do you do this already? And if not why not?