.NET Architecture & System Design Interview Question #147

What is structured logging?

Resilience, Rate Limiting, Health Checks & Observability Senior Advanced

Quick Interview Answer

Structured logging records events as named fields rather than only as preformatted text. This makes logs easier to query, aggregate, correlate, and analyze.

Detailed Explanation

Structured logging records events as named fields rather than only as preformatted text. This makes logs easier to query, aggregate, correlate, and analyze.

For example, storing OrderId as a property lets operators search across events reliably. Sensitive information such as passwords, tokens, and unnecessary personal data should not be logged.

Code Example

logger.LogInformation(
    "Order {OrderId} completed for {CustomerId}",
    order.Id,
    order.CustomerId);

// OrderId and CustomerId are fields.