ASP.NET Core MVC Interview Question #135

What are the common ASP.NET Core logging levels?

Dependency Injection, Services, Error Handling, Logging & Performance Senior Advanced

Quick Interview Answer

The standard levels are Trace, Debug, Information, Warning, Error, and Critical. Trace and Debug are highly detailed; Information records normal significant operations; Warning represents unexpected or potentially problematic conditions; Error represents failures; and Critical represents severe failures requiring immediate attention.

Detailed Explanation

The configured minimum level determines which messages are emitted. Production systems should avoid excessive high-volume logging while retaining enough information for diagnosis.

Code Example

_logger.LogDebug("Loading product {ProductId}", id);
_logger.LogInformation("Product {ProductId} loaded", id);
_logger.LogWarning("Product {ProductId} not found", id);
_logger.LogError(ex, "Failed to load product {ProductId}", id);