Okay CloudAcademy ninjas, let's review CloudWatch for our exam preparation. Basic monitoring is free with CloudWatch. Detailed monitoring comes at an additional cost. Now detailed monitoring allows you to aggregate metrics on time metrics that you define. Memory utilization is not something that is reported by default using the basic monitoring package. You can install a cloud watch agent on your EC2 instances to collect detailed metrics from EC2 instances and these can include memory utilization. Now CloudWatch does not aggregate data across regions but it can aggregate across availability zones within a region. When you do us detailed metrics, you can set a time value. Now, CloudWatch keeps data for two weeks by default. If you need to keep it longer, you can move it to Amazon S3 or Amazon Glacier and that's a great use case for a lambda function. You can have up to 5000 CloudWatch alarms per account. Now a common use case with CloudWatch monitoring is monitoring DynamoDB. You might want to know if you exceed your provisioned read-limit on a DynamoDB table for example. So if we wanna do this, we use the GET method to request the ProvisionedReadCapacityUnits metric and we create a threshold level with an alarm set when a consecutive number of periods is crossed for that DynamoDB table provisioning. If the threshold is crossed, i.e. the state changes, then you can be notified by email and you can increase the provisioning number.