Zone Transfer

Zone Transfer

Introduction

Perhaps the most popular method for gathering information about all
the computers within a domain is to request a zone transfer from the
authoritative name server for that domain. The name server will hold
information on all the computers for which it is responsible, listing
hostname against IP address.
It is strongly recommended, for reasons of load balancing and fault
tolerance, that there is more than one name server.
The main name server is called the primary name server, and all
subsequent name servers are secondary name servers. Either a primary
or secondary name server can be queried for name resolution, so it is
necessary that the information each name server has is current. To
ensure this is the case, when a secondary name server is started and at
regular, specifiable intervals thereafter, it requests a complete listing of
the computers it is responsible for from the primary name server. The
process of requesting and receiving this information is a zone transfer.