--forward-unsupported-queries works for /api/v1/query but not /api/v1/query_range. When a range query can't be served from sketches, the engine returns an error body instead of proxying to Prometheus. Since Grafana dashboards are almost entirely query_range, this breaks transparent fallback for all unaccelerated panels.
Relevant code: process_range_query_request in asap-query-engine/src/drivers/query/servers/http.rs — there's even a comment: "For now, return error - fallback for range queries can be added later."
--forward-unsupported-queriesworks for/api/v1/querybut not/api/v1/query_range. When a range query can't be served from sketches, the engine returns an error body instead of proxying to Prometheus. Since Grafana dashboards are almost entirelyquery_range, this breaks transparent fallback for all unaccelerated panels.Relevant code:
process_range_query_requestinasap-query-engine/src/drivers/query/servers/http.rs— there's even a comment: "For now, return error - fallback for range queries can be added later."