What's Actually Happening

Your Grafana dashboard fails to load, shows errors, or displays incomplete data. Panels show "No data" or loading spinners indefinitely.

The Error You'll See

```bash # Grafana UI shows: Datasource connection failed Query execution failed Timeout exceeded

# Or: Panel plugin not found ```

Why This Happens

  1. 1.Datasource down - Prometheus, InfluxDB unreachable
  2. 2.Query timeout - Query takes too long
  3. 3.Plugin missing - Required plugin not installed
  4. 4.Memory issues - Grafana OOM
  5. 5.Browser cache - Stale cached data

Step 1: Check Datasource

```bash # Test datasource connection: # In Grafana UI: Configuration > Data sources > Test

# Via API: curl -XGET http://admin:admin@localhost:3000/api/datasources/proxy/1/api/v1/query?query=up

# Check datasource health: curl -XGET http://localhost:3000/api/datasources/1/health ```

Step 2: Check Grafana Logs

```bash # View logs: docker logs grafana journalctl -u grafana-server -f

# Check for errors: grep -i error /var/log/grafana/grafana.log ```

Step 3: Restart Grafana

```bash # Docker: docker restart grafana

# Systemd: sudo systemctl restart grafana-server

# Kubernetes: kubectl rollout restart deployment/grafana ```

Step 4: Fix Query Issues

```bash # Increase query timeout: # In grafana.ini: [dataproxy] timeout = 60

# Or per datasource: # In datasource config, increase timeout

# Simplify queries: # Reduce time range # Use recording rules ```

Grafana Dashboard Loading Checklist

CheckCommandExpected
Datasource uptest connectionConnected
No errors in logsgrep errorEmpty
Query workstest queryData returned
Plugins loadedplugins listAll present

Verify the Fix

```bash # Open dashboard: # Navigate to dashboard in browser

# Check panels: # All panels show data

# Verify no errors: # Check Grafana logs ```

  • [Fix Prometheus Target Down](/articles/fix-prometheus-target-down)
  • [Fix Grafana Datasource Connection](/articles/fix-grafana-datasource-connection)