Keep documentation and test names inside reserved namespaces

Use this document to resolve one bounded operational decision: Keep documentation and test names inside reserved namespaces. Only the official source and traced locations below supply facts. Confirm applicability before acting.

Source fact:

The official RFC 2606 — Reserved Top Level DNS Names from RFC Editor / Internet Engineering Task Force supports the following bounded statements:

• The top-level names .test, .example, .invalid, and .localhost are reserved for their designated testing, documentation, invalid-name, and loopback uses. The research record locates this support at Section 2 (TLDs for Testing and Documentation Examples).
• The second-level names example.com, example.net, and example.org are reserved for examples. The research record locates this support at Section 3 (Reserved Example Second Level Domain Names).
• Using these reservations avoids collisions that can occur when test or example code names a real or subsequently delegated namespace. The research record locates this support at Section 2 (TLDs for Testing and Documentation Examples), collision rationale.

These statements are the factual basis for this document. Do not extend them into a broader assurance. Review authoritative zones, delegations, resolvers, caches, record owners, and the clients that consume the resulting answers only where the source and recorded environment align.

What the source does not establish

This RFC evidence supports only the named DNS protocol decision; it does not prove Windows implementation support or a safe production configuration. No current deployment state or change approval follows from the source alone. Validate Windows DNS roles, Active Directory-integrated data, forwarding paths, time, routing, firewalls, and registrar or registry state, and treat examples or options as conditional inputs rather than defaults.

Applicability questions

• For source statement 1 at Section 2 (TLDs for Testing and Documentation Examples), which observable configuration, record, or test can confirm applicability here?
• For source statement 2 at Section 3 (Reserved Example Second Level Domain Names), which observable configuration, record, or test can confirm applicability here?
• For source statement 3 at Section 2 (TLDs for Testing and Documentation Examples), collision rationale, which observable configuration, record, or test can confirm applicability here?
• Within authoritative zones, delegations, resolvers, caches, record owners, and the clients that consume the resulting answers, which versions, roles, and configuration states define the review population?
• Could Windows DNS roles, Active Directory-integrated data, forwarding paths, time, routing, firewalls, and registrar or registry state invalidate the test, hide a failure, or change applicability?
• Who owns the decision, and which observation requires stopping, escalation, or rollback?

DSE recommendation:

DSE recommends using the cited source as the evidence anchor for this decision. Start with applicability, then compare the observed state with the cited source. Record the source location, examined part of authoritative zones, delegations, resolvers, caches, record owners, and the clients that consume the resulting answers, observed and expected states, owner, and reason for deviation.

If the review warrants change, use a bounded implementation with prerequisites, test population, monitoring, abort criteria, and a rehearsed reversal. Sequence checks for Windows DNS roles, Active Directory-integrated data, forwarding paths, time, routing, firewalls, and registrar or registry state and sanitize protected material before retention.

Verification and evidence

Evidence should let another reviewer reproduce this decision. Retain observations beside the traced locations Section 2 (TLDs for Testing and Documentation Examples); Section 3 (Reserved Example Second Level Domain Names); Section 2 (TLDs for Testing and Documentation Examples), collision rationale. Favor zone data, packet captures, query transcripts, delegation checks, resolver configuration, and negative-answer behavior, linked to stable identifiers, time, and operator.

Retain the starting state, authorization, execution record, outcome, deviation, and final state as one review package. Move disruptive checks to an approved test path. Reopen the decision when versions, design, dependencies, ownership, or official guidance changes.

Official references

• RFC 2606 — Reserved Top Level DNS Names — RFC Editor / Internet Engineering Task Force