- Alarms are used to trigger notifications for any metric
- Alarms actions...
- Auto Scaling: increase or decrease EC2 instances "desired" count
- EC2 Actions: stop, terminate, reboot or recover an EC2 instance
- SNS notifications: send a notification into an SNS topic
- Various options (sampling, %, max, min, etc...)
- Can choose the period on which to evaluate an alarm
- Example: create a billing alarm on the CloudWatch Billing metric
- Alarm States: OK. INSUFFICIENT_DATA, ALARM