Watch & Trace: Logging and Monitoring in ASP.NET Core

As applications grow more complex and distributed, the ability to detect, diagnose, and resolve issues quickly becomes critical to their success. Watch & Trace: Logging and Monitoring in ASP.NET Core is a practical, in-depth guide for .NET developers who want to build secure, scalable, and observable applications with confidence. Whether you're working on microservices, web APIs, or serverless apps, this book gives you the tools and techniques you need to gain full visibility into your systems.
This book takes a deep dive into the logging and diagnostics capabilities of ASP.NET Core, showing you how to collect meaningful logs, monitor application health, and trace errors across services. You’ll learn how to leverage the built-in ILogger interface and extend your logging strategy using structured logging tools like Serilog. From writing your first log line to setting up a full observability pipeline with centralized log aggregation and real-time monitoring dashboards, you’ll gain step-by-step guidance every step of the way.
Explore how to use Application Insights, OpenTelemetry, and distributed tracing to track request flow, measure performance, and identify bottlenecks in real time. You'll learn to use modern monitoring tools like Grafana, Seq, and Elasticsearch to query logs, set alerts, and visualize your application's behavior. Whether you’re running a single service or managing dozens of microservices, this book equips you with the knowledge to trace problems back to their source.
Learn how to implement global exception handling, log meaningful error details, and avoid common security pitfalls like logging sensitive or personal data. Understand how to correlate logs across multiple services using trace identifiers and how to inject important contextual information into your logs at runtime. This book also covers testing your logging logic, capturing logs during unit tests, and integrating your logs into CI/CD pipelines for auditability.
You’ll also discover how to configure liveness and readiness probes, track application metrics, and visualize CPU, memory, and request statistics through telemetry platforms. Real-world code samples are included throughout, along with production-ready templates for configuring your applications for both development and enterprise-scale deployment.
Topics covered include:

• Structured logging with Serilog and custom log enrichers
• Centralized logging with Seq, ELK stack, and Grafana Loki
• Instrumenting ASP.NET Core with OpenTelemetry and Activity
• Setting up Application Insights for performance tracking
• Handling exceptions and logging error details safely
• Implementing HealthChecks, metrics, and performance diagnostics
• Setting up alerts, thresholds, and dashboards
• Logging strategies for microservices and distributed systems
• Testing and mocking log output in unit tests
• Logging in Azure Functions and serverless architectures
• Logging best practices, anti-patterns, and team standards

Whether you're a backend developer, DevOps engineer, or software architect, this book will help you build .NET applications that are observable, diagnosable, and production-ready. You’ll gain the skills to track down elusive bugs, monitor real-time performance, and confidently release code that behaves as expected in the wild.
If you're ready to take your ASP.NET Core applications to the next level with professional-grade logging and monitoring, Watch & Trace is your go-to resource.