Application Monitoring & Observability

Complete Guide to Monitoring Modern Applications

Observability is the ability to understand a system’s internal state by examining its outputs: logs, metrics, and traces. In modern distributed systems, monitoring and observability are essential for detecting issues, understanding system behavior, and ensuring reliability. This comprehensive guide covers monitoring strategies, observability pillars, tools, and best practices for maintaining healthy applications.

FATAL: Very severe error events that abort the application

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live demo · related simulation● LIVE

Honeycomb: Observability for modern software

New Relic APM: Application performance monitoring

Datadog APM: Application performance monitoring

Frequently asked questions

What is application monitoring and why is it important?

Application monitoring involves tracking the performance of your applications to identify potential issues and ensure they are functioning as expected. It’s crucial for maintaining service reliability, diagnosing problems quickly, and optimizing application efficiency.

What does ‘liveness’ mean in the context of application health checks?

Liveness probes determine whether a service is currently running and responsive. A successful liveness check indicates that the service is alive and operational, while a failed check suggests it needs to be restarted.

How does ‘readiness’ differ from ‘liveness’?

Readiness probes assess whether a service is ready to handle incoming traffic. This means the service has completed its startup process, loaded necessary data, and is prepared to serve requests effectively.

What does ‘startup’ refer to in application monitoring?

The startup phase represents the initial period when a service is being initialized. Monitoring this stage helps identify any issues that might prevent the service from starting correctly and becoming fully operational.

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Application Monitoring & Observability - Complete Guide