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Primary DNS server

Primary DNS server definition

A primary DNS server is a server that plays a crucial role in how the internet functions. It is responsible for translating human-readable domain names you type into your browser, such as www.example.com, into IP addresses, such as 192.0.2.1, that computers use to identify other devices on the network. The primary DNS server is authoritative for its zone, meaning it has the final and accurate database of DNS records for the domains within its zone. It is the definitive source of information about those domains.

See also: dns a record, dns cache

How does a primary DNS server work?

A computer finds the IP address associated with the domain name by first checking if the IP address for the domain is already known and stored in its local DNS cache. If not found, it sends a query to the DNS server assigned by your ISP, which could be a primary DNS server or a caching server. If the ISP's DNS server doesn't have the record, it performs a recursive query.

Once the primary DNS server finds the IP address, it sends this information back through the chain to your ISP's DNS server and then to your computer. It may also store the data in its local DNS cache for a specified time so the future requests for the same domain can be answered more quickly.