how can I configure cloudwatch to monitor things like CPU/RAM/Disk/IO for auto scaling groups using a wildcard?

Question

From what I have observed, cloudwatch only lets you select and monitor things by individual instance ID's, and seem to be frozen in time as soon as you hit save -- so if the instance is no longer there 10 minutes later, because it was replaced with a new one, you only get the old data

i've been trying to figure out how to create a dashboard to monitor apps running on Ec2 auto scaling groups based on something flexible, that can change over time. They share the same tag `aws:autoscaling:groupName"

How can pass in a wildcard argument for substring matching?

so far this is what i have done:

navigate to:
`Cloudwatch` > `Metrics `> `Explorer`

then under the metrics input use `EC2 Instance: CPUUtilization: Average`

under `From` i want to use a wildcard, since GroupID's will always change as new deploys roll out

`aws:autoscaling:groupName:*myGroupsPartialSubstring*`

Answer

Good question.

For Autoscaling Groups, AWS does collect metrics for the instances within an autoscaling group.

By default, basic monitoring is enabled for the autoscaling group.  If you want detailed CloudWatch monitoring, you can enable that as well in the launch template: https://docs.aws.amazon.com/autoscaling/ec2/userguide/create-launch-template.html#advanced-settings-for-your-launch-template.

More information here: https://docs.aws.amazon.com/autoscaling/ec2/userguide/enable-as-instance-metrics.html

From there, you can then look at both Autoscaling metrics and EC2 metrics: https://docs.aws.amazon.com/autoscaling/ec2/userguide/viewing-monitoring-graphs.html

The metrics you see at the autoscaling group level will be aggregated for the ec2 instances within the autoscaling group and can be viewed here: https://console.aws.amazon.com/ec2autoscaling/

how can I configure cloudwatch to monitor things like CPU/RAM/Disk/IO for auto scaling groups using a wildcard?

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