400 Bad Request - There Was An Error Returned Querying The Prometheus Api 【2025】
ares is a cross-platform, open source, multi-system emulator, focusing on accuracy and preservation.
ares v147 (2025-12-23 09:00:00)
ares is a cross-platform, open source, multi-system emulator, focusing on accuracy and preservation.
ares v147 (2025-12-23 09:00:00)
Prometheus expects a Content-Type header for POST queries ( application/x-www-form-urlencoded ). If the proxy manipulates this, Prometheus throws a 400.
Increase your step interval ( step=300 for 5m steps) or reduce your time range. 4. Header Conflicts (The Reverse Proxy Issue) If you run Prometheus behind an NGINX or AWS ALB, the proxy might strip or modify required headers. Prometheus expects a Content-Type header for POST queries
Check your up metric. If you see weird label values, you have found your problem. The "400 Bad Request" error is Prometheus's way of saying, "I don't understand what you want, and I refuse to guess." It is frustrating, but it is safe . It protects your Prometheus instance from crashing due to bad input. "I don't understand what you want
Prometheus expects a Content-Type header for POST queries ( application/x-www-form-urlencoded ). If the proxy manipulates this, Prometheus throws a 400.
Increase your step interval ( step=300 for 5m steps) or reduce your time range. 4. Header Conflicts (The Reverse Proxy Issue) If you run Prometheus behind an NGINX or AWS ALB, the proxy might strip or modify required headers.
Check your up metric. If you see weird label values, you have found your problem. The "400 Bad Request" error is Prometheus's way of saying, "I don't understand what you want, and I refuse to guess." It is frustrating, but it is safe . It protects your Prometheus instance from crashing due to bad input.