Infra Notes

Grafana shows no data, but Prometheus already has the metric

Before changing exporters or scrape configs, confirm whether the issue is actually the Grafana query, variable, or label filter.

ObservabilityGrafanaPrometheusPromQLDashboardDebugging

Problem

Grafana panel shows no data, but the metric exists in Prometheus.

Why it happens

The issue may be caused by wrong label filters, dashboard variables, namespace filters, datasource selection, or time range.

Fix / Approach

Start from raw PromQL in Prometheus, then simplify the Grafana query until the missing filter is obvious.

Command / Config

Useful checks:

  • Query metric directly in Prometheus
  • Remove dashboard variables temporarily
  • Check datasource
  • Check time range
  • Check namespace or label filters

When to use

  • Dashboard debugging
  • Kubernetes monitoring
  • Prometheus or Grafana troubleshooting

When not to use

  • When Prometheus itself does not have the metric