Description:

Application Insights is part of Azure Monitor, providing visibility into application performance, failures, user behavior, dependency health, telemetry, and availability. It helps detect issues proactively by collecting request logs, exceptions, traces, metrics, and dependency data. This control ensures that Application Insights is properly configured and linked to all relevant services, including App Services and Function Apps, to provide full observability and operational monitoring.


Rationale:

If Application Insights is not enabled, applications may operate without visibility into performance or failures. This prevents teams from detecting exceptions, latency issues, dependency failures, and performance degradation. Missing telemetry reduces diagnostic capabilities, slows incident response, and can lead to prolonged outages. Configuring Application Insights ensures proactive monitoring and supports compliance, reliability standards, and operational best practices.


Impact:

  • Enables real-time monitoring of application performance

  • Provides telemetry for troubleshooting and incident response

  • Offers analytics for performance tuning and optimization

  • Supports root cause analysis with end-to-end transaction tracking\

  • Helps meet operational and monitoring compliance requirements.


Default Value:

Application Insights is not enabled by default. Users must manually configure it or enable automatic instrumentation.


Pre-Requisites:

  • Active Azure subscription

  • Existing App Service or Function App

  • Application Insights resource (existing or to be created)

  • Permission to update App Service settings


Test Plan:

  1. Sign in to the Azure Portal.

  2. Navigate to the App Service or Function App.

  3. Under Environment variables, Open Settings.

  4. Verify APPLICATIONINSIGHTS_CONNECTION_STRING is present.

  5. Search for Application Insights in the Azure Portal.

  6. Open the linked Application Insights resource.

  7. Select Live Metrics.

  8. Generate traffic to the application (for example, open the application URL).

  9. Confirm live request metrics are displayed.

  10. If metrics are not available, follow the Implementation Steps


Implementation Steps:

  1. Sign in to the Azure Portal.

  2. Search for Application Insights and select Create.

  1. Choose the Subscription and Resource Group.

  2. Enter a Name and select the Region.

  3. Select an existing Log Analytics Workspace or create a new one.

  4. Click Review + Create, then Create.



  1. Open the newly created Application Insights resource.

  2. In the overview page, copy the Connection String.



  1. Navigate to the App Service.

  2. Under Settings, open Environment variables, in App settings.

                                   

  1. Click Add and enter:

  1. Name: APPLICATIONINSIGHTS_CONNECTION_STRING

  2. Value: Application Insights connection string

  1. Save the changes.


Backout Plan:

  1. Sign in to the Azure Portal.

  2. Navigate to the App Service.

  3. Under Settings, open Environment variables, in App settings.

  4. Locate APPLICATIONINSIGHTS_CONNECTION_STRING.

  5. Remove the setting or clear its value.

  6. Save the changes.

  7. Restart the application if prompted.

  8. (Optional) Navigate to Application Insights and delete the resource only if it is not used by any other applications.


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