LokiVLProxyClientBadRequestBurst

• Signal: bad_request client errors above 2 req/s on an endpoint for 10m.
• Likely causes: invalid query syntax, incompatible client behavior, automated retries with malformed requests.

Triage

1. sum(rate(loki_vl_proxy_client_errors_total{reason="bad_request"}[5m])) by (client, endpoint)
2. Check query-length outliers and endpoint-specific request spikes.
3. Inspect logs for parser/translation errors and request normalization rejects.

Mitigation

• Contact top offending client owners with example failing queries.
• Add client-side validation and exponential backoff.
• Apply temporary traffic controls for abusive clients.

Recovery Criteria

• bad request rate drops below alert threshold.
• retry-induced traffic amplification is no longer observed.

Prevention

Apply Deployment And Scaling Best Practices for rate-limit policy and client isolation strategy.