CloudWatch vs Prometheus
Compare AWS-native managed monitoring with open-source metrics monitoring for cloud-native environments.
Observability
Amazon CloudWatch
CloudWatch is AWS’s native monitoring service for metrics, logs, alarms, dashboards, and operational visibility. It integrates directly with AWS services and requires minimal setup inside AWS.
Observability
Prometheus
Prometheus is an open-source monitoring system built around time-series metrics, scraping, service discovery, and alerting. It is widely used in Kubernetes and cloud-native infrastructure.
Key Differences
CloudWatch is AWS-native and managed, while Prometheus is open-source and self-managed.
CloudWatch integrates directly with AWS services out of the box, while Prometheus is more flexible across non-AWS and mixed environments.
Prometheus uses a pull-based scraping model, while CloudWatch often relies on native AWS metric publishing and log integrations.
CloudWatch is easier inside AWS-only environments, while Prometheus is often stronger in Kubernetes and platform-agnostic stacks.
Prometheus typically requires additional tooling such as Grafana, while CloudWatch includes dashboards and alarms natively.
CloudWatch reduces setup effort, while Prometheus provides more control and ecosystem flexibility.
When to Use
When to use CloudWatch
Use CloudWatch when your workloads are mainly in AWS and you want managed monitoring tightly integrated with AWS services.
When to use Prometheus
Use Prometheus when you need flexible, open-source metrics monitoring across Kubernetes, cloud-native systems, or mixed environments.
Tradeoffs
CloudWatch is convenient and AWS-native, but less open and less portable outside AWS.
Prometheus is highly flexible and ecosystem-friendly, but requires more setup and maintenance.
CloudWatch is often best for AWS-first operations, while Prometheus is often best for cloud-native platform operations.
Common Mistakes
Assuming CloudWatch is always enough in Kubernetes-heavy environments.
Using Prometheus where simple AWS-native monitoring would meet the team’s needs with less operational effort.
Ignoring the difference between convenience and flexibility when evaluating monitoring tools.
Interview Tip
The short answer is: CloudWatch is AWS-native and managed, while Prometheus is open-source and cloud-native focused.