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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  Name Systems and TCP/IP Name Registration and Name Resolution            9  TCP/IP Name Systems: Host Tables and Domain Name System (DNS)                 9  TCP/IP Domain Name System (DNS)                      9  DNS Name Servers and Name Resolution                           9  DNS Name Server Concepts and Operation

DNS Name Server Functions, Name Server Architecture and General Operation 1 2 3 4 DNS Name Server Types and Roles: Primary/Master, Secondary/Slave and Caching-Only Servers

Use of Resource Records and Master Files

Each node may have a variable number of records, depending on the node type and what information is being kept for it. The resource records are added, changed or deleted when DNS information changes, by administrators who make modifications to the text master files on the server computer. These files are then read into memory by the DNS server software, parsed (interpreted) and converted into binary form. They are then ready for use in resolving DNS name requests and other queries. This is illustrated in Figure 241.

I describe both the binary RR field formats and master file format in the section on DNS messaging and formats.

DNS Name Server Functions, Name Server Architecture and General Operation 1 2 3 4 DNS Name Server Types and Roles: Primary/Master, Secondary/Slave and Caching-Only Servers