Description
EC2 basic monitoring provides most metrics in five-minute periods. Without detailed monitoring, brief load changes may be harder to analyze, but monitoring is not stopped: status check metrics are available in one-minute periods even with basic monitoring.
Detailed monitoring provides supported instance metrics in one-minute periods at an additional cost. It does not automatically add metrics that need separate collection, such as memory usage or free filesystem space.
Potential impact
- Short CPU or network load changes can be harder to identify, delaying incident response.
- Unnecessary detailed metric collection can increase costs.
Remediation
Review the workload’s response-time and observation needs, and set Monitoring to true if one-minute metrics are needed. Verify metric collection and alarms. Configure a separate collector, such as the CloudWatch agent, for required operating-system metrics, and review costs.
Examples
These excerpts show part of the same EC2 instance. Replace the AMI identifier with an actual image available in the Region.
Before
Resources:
MyEC2Instance:
Type: AWS::EC2::Instance
Properties:
ImageId: ami-12345678
InstanceType: t3.micro
Monitoring: false
This uses basic monitoring. It does not turn off all metric collection.
After
Resources:
MyEC2Instance:
Type: AWS::EC2::Instance
Properties:
ImageId: ami-12345678
InstanceType: t3.micro
Monitoring: true
This enables detailed monitoring. Configure alarms and operating-system metric collection separately.