How Can ASP.NET Core Logging Be Structured for Troubleshooting Enterprise Applications?

Effective logging in ASP.NET Core should help an engineering team answer three questions: What happened? Where did it happen? Why did it happen? ASP.NET Core provides the built-in ILogger<T> abstraction, allowing applications to write structured logs without tightly coupling business code to a specific logging provider. Instead of writing messages such as: "Something went wrong" logs should contain meaningful structured information—for example, operation name, customer/order identifier, request correlation ID, duration and exception details. Log levels should also be used deliberately: Trace/Debug – detailed diagnostic information Information – significant application events Warning – unexpected conditions that may require attention Error – failed operations Critical – severe failures affecting the application For enterprise troubleshooting, correlation IDs and distributed tracing become especially important. A request may travel through an API, database, message queue and another service. Engineers should be able to trace that transaction across components. Sensitive information must never be casually written to logs. Passwords, tokens, connection strings and confidential business data should be protected or excluded. Logs should also be centralised into an observability platform such as Azure Monitor/Application Insights or another approved logging system. The goal is not to generate more logs. The goal is to generate structured, searchable and actionable telemetry that allows engineers to diagnose failures quickly and understand application behaviour in production.