AZ-400 Designing and Implementing Microsoft DevOps Solutions Exam

Inspect Distributed Tracing by using Application Insights

Correlate End-to-End Requests

Distributed tracing with Application Insights provides a detailed view of how requests flow through your application. This is especially important for applications built with microservices or other complex distributed systems. By using distributed tracing, you can identify performance issues and failures more effectively.

Configuring Application Insights SDK

To enable end-to-end tracing, you need to configure the Application Insights SDK in each microservice. This configuration allows operation identifiers to propagate, ensuring that all parts of a request are linked together. For .NET applications, you can integrate Application Insights with your logging framework such as ILogger. For other programming languages, you should use the appropriate Azure Monitor exporter or OpenTelemetry SDK to send trace telemetry.

Examining Application Map

The Application Map in Application Insights visually displays how various services interact within your application. This map helps reconstruct request paths, showing dependencies between different services. By examining trace spans, you can quickly identify where specific requests travel and diagnose potential bottlenecks or failures in your system.

Analyzing Telemetry

Detailed telemetry analysis focuses on uncovering latency sources and understanding error propagation. Collected telemetry includes:

• Trace logs: Which are messages like debug and info logs that act as breadcrumbs, providing insights into what the application was doing at specific times.
• Custom events & metrics: These are manually instrumented data points that can highlight significant operations or unusual behaviors.

Importance and Best Practices

Enabling trace logs helps during investigations by showing contexts around issues, such as what operations were occurring when errors happened. Best practices include:

• Collecting Information-level logs in production.
• Ensuring each log message has contextual identifiers like operation IDs, which Application Insights attaches automatically.

In conclusion, careful setup of Application Insights across your services allows comprehensive tracing of end-to-end requests. This provides visibility into the health and performance of distributed applications. By analyzing this telemetry, you can significantly improve system reliability and user experience.