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CNAME Record Model

Added in version 1.2.0 — CNAME exclusivity

When CNAME exclusivity is enabled (via the CNAME_RESTRICTION_ENABLED configuration), the app enforces CNAME rules per RFC 1912 §2.4:

  • A CNAME cannot co‑exist with any other record type that has the exact same name in the same zone.
  • Conversely, a non‑CNAME record cannot co‑exist where a CNAME with the exact same name already exists in the same zone.
  • Name comparison is exact:
    • A zone‑qualified name such as host.example.com is distinct from the relative host under zone example.com.
    • A trailing dot is ignored (e.g., host.example.com. is treated as host.example.com).

Additional constraints:

  • Database uniqueness for CNAME is (name, alias, zone).

Examples:

  • Blocked: A(name="www") and CNAME(name="www") in the same zone.
  • Allowed: A(name="www") and CNAME(name="www.example.com") in zone example.com.
  • Allowed: A(name="www") and CNAME(name="www.example.com.") (trailing dot ignored).

See the installation guide for configuration options.