Networking / Beginners

Primary and Secondary Servers

The primary DNS servers are owned and managed by specific domains. These servers provide authoritative replies for hostname resolution within the domain. For example, the domain ibm.com is managed by a set of IBM-owned name servers such as ns.watson.ibm.com and ns.austin.ibm.com. These name servers can resolve all hostnames within their domain.

Secondary name servers provide authoritative responses but may not be directly owned or managed by the domain. Secondary servers receive periodic updates from primary servers. These updates, or zone transfers, are accomplished through a TCP connection. All authoritative information from the primary is transferred to the secondary.

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