spec 1 linked patterns checked
MDN HTTP 503 Service Unavailable
Documents 503 as a temporary server-not-ready response, common maintenance or overload causes, Retry-After recovery timing, user-friendly response pages, support links, request identifiers, and cache caution.
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Pattern Decisions This Source Supports
| Pattern | Supported decision | Required contract | Claim note |
|---|---|---|---|
| Service unavailable page | Choose service unavailable page when the user cannot proceed because the service entry point, transaction, or route is closed or server-side capacity is unavailable. | The page replaces the affected service route until the service can safely handle requests again. | MDN documents 503 temporary unavailability, maintenance and overload causes, Retry-After timing, user-friendly pages, request IDs, and cache caution. |
Comparisons supported by this source
- Service unavailable page vs error state vs offline state vs site alert
MDN documents 503 as temporary server-not-ready status with maintenance or overload causes, Retry-After timing, support links, request IDs, and cache caution.
Evidence Role
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Publisher: MDN Web Docs. Last checked: .