gem-llm-gateway-debug

A 401 invalid API key error occurs when the gateway authentication middleware rejects a request due to misconfigured API key hashing or salt values. Validating Bearer key flows and checking admin key management configurations will pinpoint and resolve the authentication failure.

To fix unknown_model mapping mismatches in a vLLM proxy, you must correct the upstream routing configurations that map requested model names to their specific vLLM upstreams. Diagnosing the model list behavior helps localize these misconfigurations quickly.

Broken streaming SSE pass-through under /v1/chat/completions is caused by disrupted SSE chunk transmission or improper [DONE] termination. You need to perform streaming reliability checks to ensure proper chunk pass-through while keeping async usage logging non-blocking.

Troubleshooting Gateway 500 responses and QueuePool saturation requires running endpoint-first diagnostics on health and readiness endpoints. These failures often point to specific remediation paths like applying SQLite WAL recovery or resolving underlying proxy upstream connection issues.

To validate RPM, concurrency, and daily token quota enforcement in an API gateway, you must inspect the rate limiting and quota enforcement middleware configurations. Checking these quota parameters ensures the gateway properly restricts traffic according to defined limits.

Missing or incorrect Prometheus metrics occur when the gateway fails to properly expose or record monitoring data. Validating the metrics endpoint behavior and ensuring async usage logs record without blocking will restore accurate metric reporting.