Three ways in
| Source | How |
|---|---|
| CloudWatch alarms | SNS subscription; ALARM opens, OK closes |
| Your services | Node, Go or Python SDK in the container or function |
| Terraform | npx pagerless connect writes pagerless.tf |
Fixes
Through an IAM role you create from a CloudFormation link, with an external ID: ECS back to the previous task definition, force a new deployment or change desired count; Lambda alias back to the previous version or change reserved concurrency; Amplify re-runs the last good build.