DNS Zone File

What Does DNS Zone File Mean?

A Domain Name System zone file (DNS zone file) is a simple text file which is automatically bundled with DNS records. The file contains all the necessary information of all resources records for the particular domain. Alternatively, it can also contain the complete Internet Protocol to domain mapping of the domain.


DNS zone files help in Domain Name System management. The files provide valuable information such as the email address of the admin,
DNS records, the name servers involved and other additional information.

Techopedia Explains DNS Zone File

A DNS zone file can be a DNS master file or a file which can be used to provide the DNS cache contents. DNS zone files are created in such a way that they are portable for any domain name system server. The DNS files can easily be edited or modified with the help of text editors such as EMACS or VIM.

In a typical Domain Name System file, every line can only hold one record. The file should start with time to live (TTL), the time duration to keep the Domain Name System records in the DNS server’s cache. Another mandatory record in the DNS zone file is the start of authority (SOA) record. It provides the primary authoritative name server for the specific Domain Name System zone.

After these records, additional records can be added. After adding a record for a particular hostname, the hostname must end with a period. Comments can also be added to DNS zone file with the help of a semicolon. In the case of multiple-line comments, the representation is done with the help of brackets, with the comments beginning with a semicolon. When the multiple-line comments end, they are closed with the help of a bracket symbol placed on the single line.


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Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.