A DNS zone is a distinct portion of the Domain Name System namespace that is managed by a specific organization or administrator. This administrative space allows for more granular control of DNS components, such as authoritative nameservers. A zone starts at a domain name and extends down to include all subdomains, except those for which other zones are defined.
Zones define the boundaries of technical and administrative authority. Effective zone management is important for maintaining the integrity of an organization's naming structure and ensuring that changes in one part of the namespace do not interfere with others.
Avoid overly flat zone structures. Delegating subdomains to separate zones (e.g., dev.example.com, prod.example.com) allows for isolated management and reduces the blast radius of a configuration error. This separation enables different teams or automated systems to manage their own infrastructure without requiring access to the root zone, supporting the principle of least privilege.