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Startup Errors

Scenario: Container startup fails or app never becomes healthy after deployment/restart. Data Source: AppServiceConsoleLogs Purpose: Surfaces recent startup/runtime error signatures from console output.

graph TD
    A[AppServiceConsoleLogs] -->|Keyword Filter| B[error / exception / traceback]
    B --> C[Timeline of Error Messages]
    C --> D[Identify Boot Failure Pattern]

Run It in the Portal

Tighten the blade-level Time range to Last hour so it matches the ago(1h) filter inside the query. The query projects TimeGenerated and ResultDescription in descending order, so results render as a tabular grid rather than a timechart.

Query

AppServiceConsoleLogs
| where TimeGenerated > ago(1h)
| where ResultDescription has_any ("error", "Error", "ERROR", "exception", "Exception", "failed", "Failed", "traceback", "Traceback")
| project TimeGenerated, ResultDescription
| order by TimeGenerated desc

Interpretation Notes

  • Normal: few/no fatal startup errors; expected informational logs dominate.
  • Abnormal: repeated exceptions, traceback bursts, or fatal initialization messages.
  • Reading tip: look for repeated identical stack traces to identify deterministic boot failures.

Limitations

  • Console log availability depends on diagnostic configuration and app logging behavior.
  • Keyword search may include non-fatal lines or miss framework-specific error formats.
  • This query cannot prove whether App Service health probes succeeded.

See Also

Sources