I want to limit DNS over TCP 53 to the servers that do zone transfers with me. Will this in any way affect resolvers that get responses bigger than a UDP packet will allow ? The DNS rfc states that the TC bit is set in the DNS header, but it does not specify what if any action is taken by the resolver subsequent to that; i remember hearing that the resolver then uses TCP as the transport for the query.
Can anyone help me on this one ? novitiate
