AWS CloudWatch has reserved namespaces that begin with 'AWS/' for its own internal services and metrics. These namespaces are used by AWS to
publish official service metrics such as EC2 instance metrics, Lambda function metrics, S3 bucket metrics, and others. When you attempt to publish
custom metrics using a namespace that begins with 'AWS/', you are essentially trying to use a reserved namespace that conflicts with AWS’s own metric
publishing system.
What is the potential impact?
Using AWS service namespaces can lead to metric publishing failures, data corruption, or unexpected behavior in CloudWatch dashboards. It may also
cause confusion between your custom metrics and official AWS service metrics, making monitoring and troubleshooting more difficult. Additionally, AWS
may reject such metric publications or they may interfere with existing service metrics.
