CDN object storage is not configured
storage-server-policy returned 503 CDN object storage is not configured. when a CDN server is used without complete object-storage configuration.
Why this happens
CDN server row exists but bucket/credentials/endpoint are missing or invalid. Distinct from needing the CDN premium plugin (Phase 52).
Diagnose and fix
1. Admin → CDN server settings — complete credentials and test connection (CDN credentials and test connection).
2. Confirm public URL / custom domain as required (CDN custom domain / public URL).
3. Retry the storage operation after save.
4. See Add a CDN server (providers overview) and Storage.