AWS CloudWatch
Learn about AWS CloudWatch, a key monitoring service.
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CloudWatch
CloudWatch is a monitoring tool for AWS resources and applications. It allows us to view metrics and logs from multiple AWS services and create alarms and actions based on them. CloudWatch is an essential service for automating changes in AWS when a certain threshold is breached. It’s a regional service, and it doesn’t aggregate data across regions.
CloudWatch metrics
Most AWS services put their metrics into CloudWatch, and users can retrieve statistics and set up alarms and events based on the statistics. For example, we can set an alarm to scale up an ASG when the CPUUtilization metric reaches the 70% threshold.
Points to note:
- Each CloudWatch metric must have a timestamp.
- We can use metric math in CloudWatch to query multiple metrics and create a new aggregated metric.
- Metrics can’t be deleted. They expire after 15 months.
The following illustration shows the VolumeReadOps and VolumeWriteOps metrics for an EBS volume over the last 37 hours.
Namespaces
A namespace is a container for CloudWatch metrics. For example, the default metrics from a service go to the AWS/service_name namespace (like AWS/EC2, AWS/RDS, etc.).
Dimensions
Dimensions ...