# Monitor your instances using CloudWatch
You can monitor your instances using Amazon CloudWatch, which collects and processes raw data from Amazon EC2 into readable, near real-time metrics. These statistics are recorded for a period of 15 months, so that you can access historical information and gain a better perspective on how your web application or service is performing.
By default, Amazon EC2 sends metric data to CloudWatch in 5-minute periods. To send metric data for your instance to CloudWatch in 1-minute periods, you can enable detailed monitoring on the instance. For more information, see [Manage detailed monitoring for your EC2 instances](manage-detailed-monitoring.md).
The Amazon EC2 console displays a series of graphs based on the raw data from Amazon CloudWatch. Depending on your needs, you might prefer to get data for your instances from Amazon CloudWatch instead of the graphs in the console.
For Amazon CloudWatch billing and cost information, see [ CloudWatch billing and cost](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch_billing.html) in the *Amazon CloudWatch User Guide*.
**Topics**
+ [
# Manage CloudWatch alarms for your EC2 instances in the Amazon EC2 console
](ec2-instance-alarms.md)
+ [
# Manage detailed monitoring for your EC2 instances
](manage-detailed-monitoring.md)
+ [
# CloudWatch metrics that are available for your instances
](viewing_metrics_with_cloudwatch.md)
+ [
# Install and configure the CloudWatch agent using the Amazon EC2 console to add additional metrics
](install-and-configure-cloudwatch-agent-using-ec2-console.md)
+ [
# Statistics for CloudWatch metrics for your instances
](monitoring_get_statistics.md)
+ [
# View the monitoring graphs for your instances
](graphs-in-the-aws-management-console.md)
+ [
# Create a CloudWatch alarm for an instance
](using-cloudwatch-createalarm.md)
+ [
# Create alarms that stop, terminate, reboot, or recover an instance
](UsingAlarmActions.md)
# Manage CloudWatch alarms for your EC2 instances in the Amazon EC2 console
From the **Instances** screen in the Amazon EC2 console, you can manage the Amazon CloudWatch alarms for your instances. In the **Instances** table, the **Alarm status** column provides two console controls: a control for viewing alarms, and another for creating or editing them. The following screenshot indicates these console controls, numbered **1** (**View alarms**) and **2** (a **\$1** sign for creating or editing an alarm).
![\[The controls in the Instances table in the EC2 console for viewing and creating alarms. 1. View alarms 2. Plus sign symbol.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/instance-alarms.png)
## View alarms from the Instances screen
You can view each instance's alarms from the **Instances** screen.
**To view an instance's alarm from the Instances screen**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. In the **Instances** table, for your chosen instance, choose **View alarms** (numbered **1** in the preceding screenshot).
1. In the **Alarm details for *i-1234567890abcdef0*** window, choose the alarm name to view the alarm in the CloudWatch console.
## Create alarms from the Instances screen
You can create an alarm for each instance from the **Instances** screen.
**To create an alarm for an instance from the Instances screen**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. In the **Instances** table, for your chosen instance, choose the plus sign (numbered **2** in the preceding screenshot).
1. In the **Manage CloudWatch alarms** screen, create your alarm. For more information, see [Create a CloudWatch alarm for an instance](using-cloudwatch-createalarm.md).
## Edit alarms from the Instances screen
You can edit the alarm for an instance from the **Instances** screen.
**To edit an alarm for an instance from the Instances screen**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. In the **Instances** table, for your chosen instance, choose the plus sign (numbered **2** in the preceding screenshot).
1. In the **Manage CloudWatch alarms** screen, edit your alarm. For more information, see [Edit or delete a CloudWatch alarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/Manage-CloudWatch-Alarm.html#Edit-CloudWatch-Alarm) in the *Amazon CloudWatch User Guide*.
# Manage detailed monitoring for your EC2 instances
Amazon CloudWatch provides two categories of monitoring: *basic monitoring* and *detailed monitoring*. By default, your instance is configured for basic monitoring. You can optionally enable detailed monitoring to help you more quickly identify and act on operational issues. You can enable or turn off detailed monitoring at launch or when the instance is running or stopped.
Enabling detailed monitoring on an instance does not affect the monitoring of its attached EBS volumes. For more information, see [Amazon CloudWatch metrics for Amazon EBS](https://docs.aws.amazon.com/ebs/latest/userguide/using_cloudwatch_ebs.html).
The following table highlights the differences between basic monitoring and detailed monitoring for your instances.
| Monitoring type | Description | Charges |
| --- | --- | --- |
| Basic monitoring | Status check metrics are available in 1-minute periods. All other metrics are available in 5-minute periods. | No charge. |
| Detailed monitoring | You can get metrics in 1-minute periods, provided you enable detailed monitoring for the instance. Once you've enabled detailed monitoring, you can aggregate the data across groups of similar instances. | You are charged per metric that Amazon EC2 sends to CloudWatch. You are not charged for data storage. For more information, see Paid tier on the [Amazon CloudWatch pricing page](https://aws.amazon.com/cloudwatch/pricing/#Paid_tier). |
**Topics**
+ [
## Required permissions
](#iam-detailed-monitoring)
+ [
## Enable detailed monitoring at launch
](#enable-detailed-monitoring)
+ [
## Manage detailed monitoring
](#disable-detailed-monitoring)
## Required permissions
To enable detailed monitoring for an instance, your user must have permission to use the [https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_MonitorInstances.html](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_MonitorInstances.html) API action. To turn off detailed monitoring for an instance, your user must have permission to use the [https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_UnmonitorInstances.html](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_UnmonitorInstances.html) API action.
## Enable detailed monitoring at launch
Use the following procedures to enable detailed monitoring at launch. By default, your instance uses basic monitoring.
------
#### [ Console ]
**To enable detailed monitoring when launching an instance**
When launching an instance using the Amazon EC2 console, under **Advanced details**, select the **Detailed CloudWatch monitoring** checkbox.
------
#### [ AWS CLI ]
**To enable detailed monitoring when launching an instance**
Use the [run-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/run-instances.html) command with the `--monitoring` option.
```
--monitoring Enabled=true
```
------
#### [ PowerShell ]
**To enable detailed monitoring when launching an instance**
Use the [New-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/New-EC2Instance.html) cmdlet with the `-Monitoring` parameter.
```
-Monitoring $true
```
------
## Manage detailed monitoring
Use the following procedures to manage detailed monitoring for a running or stopped instance.
------
#### [ Console ]
**To manage detailed monitoring**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instance.
1. Choose **Actions**, **Monitor and troubleshoot**, **Manage detailed monitoring**.
1. On the **Detailed monitoring** page, for **Detailed monitoring**, do one of the following:
+ Detailed monitoring – Select **Enable**.
+ Basic monitoring – Clear **Enable**.
1. Choose **Confirm**.
------
#### [ AWS CLI ]
**To enable detailed monitoring**
Use the following [monitor-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/monitor-instances.html) command.
```
aws ec2 monitor-instances --instance-ids i-1234567890abcdef0
```
**To disable detailed monitoring**
Use the [unmonitor-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/unmonitor-instances.html) command.
```
aws ec2 unmonitor-instances --instance-ids i-1234567890abcdef0
```
------
#### [ PowerShell ]
**To enable detailed monitoring**
Use the [Start-EC2InstanceMonitoring](https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2InstanceMonitoring.html) cmdlet.
```
Start-EC2InstanceMonitoring -InstanceId i-1234567890abcdef0
```
**To disable detailed monitoring**
Use the [Stop-EC2InstanceMonitoring](https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2InstanceMonitoring.html) cmdlet.
```
Stop-EC2InstanceMonitoring -InstanceId i-1234567890abcdef0
```
------
# CloudWatch metrics that are available for your instances
Amazon EC2 sends metrics to Amazon CloudWatch. You can use the AWS Management Console, the AWS CLI, or an API to list the metrics that Amazon EC2 sends to CloudWatch. By default, each data point covers the 5 minutes that follow the start time of activity for the instance. If you've enabled detailed monitoring, each data point covers the next minute of activity from the start time. Note that for the Minimum, Maximum, and Average statistics, the minimum granularity for the metrics that EC2 provides is 1 minute.
For information about how to view the available metrics using the AWS Management Console or the AWS CLI, see [View available metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/viewing_metrics_with_cloudwatch.html) in the *Amazon CloudWatch User Guide*.
For information about getting the statistics for these metrics, see [Statistics for CloudWatch metrics for your instances](monitoring_get_statistics.md).
**Topics**
+ [
## Instance metrics
](#ec2-cloudwatch-metrics)
+ [
## Accelerator metrics
](#accelerator-metrics)
+ [
## CPU credit metrics
](#cpu-credit-metrics)
+ [
## Dedicated Host metrics
](#dh-metrics)
+ [
## Amazon EBS metrics for Nitro-based instances
](#ebs-metrics-nitro)
+ [
## Status check metrics
](#status-check-metrics)
+ [
## Traffic mirroring metrics
](#traffic-mirroring-metrics)
+ [
## Auto Scaling group metrics
](#autoscaling-metrics)
+ [
## Amazon EC2 metric dimensions
](#ec2-cloudwatch-dimensions)
+ [
## Amazon EC2 usage metrics
](#service-quota-metrics)
## Instance metrics
The `AWS/EC2` namespace includes the following instance metrics.
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| CPUUtilization | The percentage of physical CPU time that Amazon EC2 uses to run the EC2 instance, which includes time spent to run both the user code and the Amazon EC2 code. At a very high level, `CPUUtilization` is the sum of guest `CPUUtilization` and hypervisor `CPUUtilization`. Tools in your operating system can show a different percentage than CloudWatch due to factors such as legacy device simulation, configuration of non-legacy devices, interrupt-heavy workloads, live migration, and live update. | Percent | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| DiskReadOps | Completed read operations from all instance store volumes available to the instance in a specified period of time. To calculate the average I/O operations per second (IOPS) for the period, divide the total operations in the period by the number of seconds in that period. If there are no instance store volumes, either the value is 0 or the metric is not reported. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| DiskWriteOps | Completed write operations to all instance store volumes available to the instance in a specified period of time. To calculate the average I/O operations per second (IOPS) for the period, divide the total operations in the period by the number of seconds in that period. If there are no instance store volumes, either the value is 0 or the metric is not reported. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| DiskReadBytes | Bytes read from all instance store volumes available to the instance. This metric is used to determine the volume of the data the application reads from the hard disk of the instance. This can be used to determine the speed of the application. The number reported is the number of bytes received during the period. If you are using basic (5-minute) monitoring, you can divide this number by 300 to find Bytes/second. If you have detailed (1-minute) monitoring, divide it by 60. You can also use the CloudWatch metric math function `DIFF_TIME` to find the bytes per second. For example, if you have graphed `DiskReadBytes` in CloudWatch as `m1`, the metric math formula `m1/(DIFF_TIME(m1))` returns the metric in bytes/second. For more information about `DIFF_TIME` and other metric math functions, see [Use metric math](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/using-metric-math.html) in the *Amazon CloudWatch User Guide*. If there are no instance store volumes, either the value is 0 or the metric is not reported. | Bytes | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| DiskWriteBytes | Bytes written to all instance store volumes available to the instance. This metric is used to determine the volume of the data the application writes onto the hard disk of the instance. This can be used to determine the speed of the application. The number reported is the number of bytes received during the period. If you are using basic (5-minute) monitoring, you can divide this number by 300 to find Bytes/second. If you have detailed (1-minute) monitoring, divide it by 60. You can also use the CloudWatch metric math function `DIFF_TIME` to find the bytes per second. For example, if you have graphed `DiskWriteBytes` in CloudWatch as `m1`, the metric math formula `m1/(DIFF_TIME(m1))` returns the metric in bytes/second. For more information about `DIFF_TIME` and other metric math functions, see [Use metric math](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/using-metric-math.html) in the *Amazon CloudWatch User Guide*. If there are no instance store volumes, either the value is 0 or the metric is not reported. | Bytes | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| MetadataNoToken | The number of times the Instance Metadata Service (IMDS) was successfully accessed using a method that does not use a token. This metric is used to determine if there are any processes accessing instance metadata that are using Instance Metadata Service Version 1 (IMDSv1), which does not use a token. If all requests use token-backed sessions, i.e., Instance Metadata Service Version 2 (IMDSv2), the value is 0. For more information, see [Transition to using Instance Metadata Service Version 2](instance-metadata-transition-to-version-2.md). | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| MetadataNoTokenRejected | The number of times an IMDSv1 call was attempted after IMDSv1 was disabled. If this metric appears, it indicates that an IMDSv1 call was attempted and rejected. You can either re-enable IMDSv1 or make sure all of your calls use IMDSv2. For more information, see [Transition to using Instance Metadata Service Version 2](instance-metadata-transition-to-version-2.md). | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| NetworkIn | The number of bytes received by the instance on all network interfaces. This metric identifies the volume of incoming network traffic to a single instance. The number reported is the number of bytes received during the period. If you are using basic (5-minute) monitoring and the statistic is Sum, you can divide this number by 300 to find Bytes/second. If you have detailed (1-minute) monitoring and the statistic is Sum, divide it by 60. | Bytes | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| NetworkOut | The number of bytes sent out by the instance on all network interfaces. This metric identifies the volume of outgoing network traffic from a single instance. The number reported is the number of bytes sent during the period. If you are using basic (5-minute) monitoring and the statistic is Sum, you can divide this number by 300 to find Bytes/second. If you have detailed (1-minute) monitoring and the statistic is Sum, divide it by 60. | Bytes | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| NetworkPacketsIn | The number of packets received by the instance on all network interfaces. This metric identifies the volume of incoming traffic in terms of the number of packets on a single instance. This metric is available for basic monitoring only (5-minute periods). To calculate the number of packets per second (PPS) your instance received for the 5 minutes, divide the Sum statistic value by 300. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| NetworkPacketsOut | The number of packets sent out by the instance on all network interfaces. This metric identifies the volume of outgoing traffic in terms of the number of packets on a single instance. This metric is available for basic monitoring only (5-minute periods). To calculate the number of packets per second (PPS) your instance sent for the 5 minutes, divide the Sum statistic value by 300. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
## Accelerator metrics
The `AWS/EC2` namespace includes the following accelerator metric for your [accelerated computing instances](https://docs.aws.amazon.com/ec2/latest/instancetypes/ac.html). Only supported on a subset of accelerated computing instance types.
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| GPUPowerUtilization | Active power usage as a percentage of maximum active power. | Percent | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
## CPU credit metrics
The `AWS/EC2` namespace includes the following CPU credit metrics for your [burstable performance instances](burstable-performance-instances.md).
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| CPUCreditUsage | The number of CPU credits spent by the instance for CPU utilization. One CPU credit equals one vCPU running at 100% utilization for one minute or an equivalent combination of vCPUs, utilization, and time (for example, one vCPU running at 50% utilization for two minutes or two vCPUs running at 25% utilization for two minutes). CPU credit metrics are available at a 5-minute frequency only. If you specify a period greater than five minutes, use the `Sum` statistic instead of the `Average` statistic. | Credits (vCPU-minutes) | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| CPUCreditBalance | The number of earned CPU credits that an instance has accrued since it was launched or started. For T2 Standard, the `CPUCreditBalance` also includes the number of launch credits that have been accrued. Credits are accrued in the credit balance after they are earned, and removed from the credit balance when they are spent. The credit balance has a maximum limit, determined by the instance size. After the limit is reached, any new credits that are earned are discarded. For T2 Standard, launch credits do not count towards the limit. The credits in the `CPUCreditBalance` are available for the instance to spend to burst beyond its baseline CPU utilization. When an instance is running, credits in the `CPUCreditBalance` do not expire. When a T3 or T3a instance stops, the `CPUCreditBalance` value persists for seven days. Thereafter, all accrued credits are lost. When a T2 instance stops, the `CPUCreditBalance` value does not persist, and all accrued credits are lost. CPU credit metrics are available at a 5-minute frequency only. | Credits (vCPU-minutes) | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| CPUSurplusCreditBalance | The number of surplus credits that have been spent by an `unlimited` instance when its `CPUCreditBalance` value is zero. The `CPUSurplusCreditBalance` value is paid down by earned CPU credits. If the number of surplus credits exceeds the maximum number of credits that the instance can earn in a 24-hour period, the spent surplus credits above the maximum incur an additional charge. CPU credit metrics are available at a 5-minute frequency only. | Credits (vCPU-minutes) | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| CPUSurplusCreditsCharged | The number of spent surplus credits that are not paid down by earned CPU credits, and which thus incur an additional charge. Spent surplus credits are charged when any of the following occurs: [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) CPU credit metrics are available at a 5-minute frequency only. | Credits (vCPU-minutes) | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
## Dedicated Host metrics
The `AWS/EC2` namespace includes the following metrics for T3 Dedicated Hosts.
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| DedicatedHostCPUUtilization | The percentage of allocated compute capacity that is currently in use by the instances running on the Dedicated Host. | Percent | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
## Amazon EBS metrics for Nitro-based instances
The `AWS/EC2` namespace includes additional Amazon EBS metrics for volumes that are attached to Nitro-based instances that are not bare metal instances.
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| InstanceEBSIOPSExceededCheck | Reports whether an application attempted to drive IOPS that exceeds the maximum EBS IOPS limits for the instance within the last minute. This metric can be either `0` (IOPS not exceeded) or `1` (IOPS exceeded). | None | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| InstanceEBSThroughputExceededCheck | Reports whether an application attempted to drive throughput that exceeds the maximum EBS throughput limits for the instance within the last minute. This metric can be either `0` (throughput not exceeded) or `1` (throughput exceeded). | None | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| EBSReadOps | Completed read operations from all Amazon EBS volumes attached to the instance in a specified period of time. To calculate the average read I/O operations per second (Read IOPS) for the period, divide the total operations in the period by the number of seconds in that period. If you are using basic (5-minute) monitoring, you can divide this number by 300 to calculate the Read IOPS. If you have detailed (1-minute) monitoring, divide it by 60. You can also use the CloudWatch metric math function `DIFF_TIME` to find the operations per second. For example, if you have graphed `EBSReadOps` in CloudWatch as `m1`, the metric math formula `m1/(DIFF_TIME(m1))` returns the metric in operations/second. For more information about `DIFF_TIME` and other metric math functions, see [Use metric math](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/using-metric-math.html) in the *Amazon CloudWatch User Guide*. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| EBSWriteOps | Completed write operations to all EBS volumes attached to the instance in a specified period of time. To calculate the average write I/O operations per second (Write IOPS) for the period, divide the total operations in the period by the number of seconds in that period. If you are using basic (5-minute) monitoring, you can divide this number by 300 to calculate the Write IOPS. If you have detailed (1-minute) monitoring, divide it by 60. You can also use the CloudWatch metric math function `DIFF_TIME` to find the operations per second. For example, if you have graphed `EBSWriteOps` in CloudWatch as `m1`, the metric math formula `m1/(DIFF_TIME(m1))` returns the metric in operations/second. For more information about `DIFF_TIME` and other metric math functions, see [Use metric math](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/using-metric-math.html) in the *Amazon CloudWatch User Guide*. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| EBSReadBytes | Bytes read from all EBS volumes attached to the instance in a specified period of time. The number reported is the number of bytes read during the period. If you are using basic (5-minute) monitoring, you can divide this number by 300 to find Read Bytes/second. If you have detailed (1-minute) monitoring, divide it by 60. You can also use the CloudWatch metric math function `DIFF_TIME` to find the bytes per second. For example, if you have graphed `EBSReadBytes` in CloudWatch as `m1`, the metric math formula `m1/(DIFF_TIME(m1))` returns the metric in bytes/second. For more information about `DIFF_TIME` and other metric math functions, see [Use metric math](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/using-metric-math.html) in the *Amazon CloudWatch User Guide*. | Bytes | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| EBSWriteBytes | Bytes written to all EBS volumes attached to the instance in a specified period of time. The number reported is the number of bytes written during the period. If you are using basic (5-minute) monitoring, you can divide this number by 300 to find Write Bytes/second. If you have detailed (1-minute) monitoring, divide it by 60. You can also use the CloudWatch metric math function `DIFF_TIME` to find the bytes per second. For example, if you have graphed `EBSWriteBytes` in CloudWatch as `m1`, the metric math formula `m1/(DIFF_TIME(m1))` returns the metric in bytes/second. For more information about `DIFF_TIME` and other metric math functions, see [Use metric math](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/using-metric-math.html) in the *Amazon CloudWatch User Guide*. | Bytes | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| EBSIOBalance% | Provides information about the percentage of I/O credits remaining in the burst bucket. This metric is available for basic monitoring only. This metric is available only for some `*.4xlarge` instance sizes and smaller that burst to their maximum performance for only 30 minutes at least once every 24 hours. The `Sum` statistic is not applicable to this metric. | Percent | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| EBSByteBalance% | Provides information about the percentage of throughput credits remaining in the burst bucket. This metric is available for basic monitoring only. This metric is available only for some `*.4xlarge` instance sizes and smaller that burst to their maximum performance for only 30 minutes at least once every 24 hours. The `Sum` statistic is not applicable to this metric. | Percent | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
For information about the metrics provided for your EBS volumes, see [Metrics for Amazon EBS volumes](https://docs.aws.amazon.com/ebs/latest/userguide/using_cloudwatch_ebs.html#ebs-volume-metrics) in the *Amazon EBS User Guide*. For information about the metrics provided for your EC2 Fleets and Spot Fleets, see [Monitor your EC2 Fleet or Spot Fleet using CloudWatch](ec2-fleet-cloudwatch-metrics.md).
## Status check metrics
By default, status check metrics are available at a 1-minute frequency at no charge. For a newly-launched instance, status check metric data is only available after the instance has completed the initialization state (within a few minutes of the instance entering the `running` state). For more information about EC2 status checks, see [Status checks for Amazon EC2 instances](monitoring-system-instance-status-check.md).
The `AWS/EC2` namespace includes the following status check metrics.
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| StatusCheckFailed | Reports whether the instance has passed all status checks in the last minute. This metric can be either `0` (passed) or `1` (failed). By default, this metric is available at a 1-minute frequency at no charge. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| StatusCheckFailed\$1Instance | Reports whether the instance has passed the instance status check in the last minute. This metric can be either `0` (passed) or `1` (failed). By default, this metric is available at a 1-minute frequency at no charge. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| StatusCheckFailed\$1System | Reports whether the instance has passed the system status check in the last minute. This metric can be either `0` (passed) or `1` (failed). By default, this metric is available at a 1-minute frequency at no charge. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
| StatusCheckFailed\$1AttachedEBS | Reports whether the instance has passed the attached EBS status check in the last minute. This metric can be either `0` (passed) or `1` (failed). By default, this metric is available at a 1-minute frequency at no charge. | Count | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
The `AWS/EBS` namespace includes the following status check metric.
| Metric | Description | Unit | Meaningful statistics |
| --- | --- | --- | --- |
| VolumeStalledIOCheck | **Note: **For Nitro instances only. Not published for volumes attached to Amazon ECS and AWS Fargate tasks. Reports whether a volume has passed or failed a *stalled IO check* in the last minute. This metric can be either `0` (passed) or `1` (failed). | None | [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/viewing_metrics_with_cloudwatch.html) |
## Traffic mirroring metrics
The `AWS/EC2` namespace includes metrics for mirrored traffic. For more information, see [Monitor mirrored traffic using Amazon CloudWatch](https://docs.aws.amazon.com/vpc/latest/mirroring/traffic-mirror-cloudwatch.html) in the *Amazon VPC Traffic Mirroring Guide*.
## Auto Scaling group metrics
The `AWS/AutoScaling` namespace includes metrics for Auto Scaling groups. For more information, see [Monitor CloudWatch metrics for your Auto Scaling groups and instances](https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-cloudwatch-monitoring.html) in the *Amazon EC2 Auto Scaling User Guide*.
## Amazon EC2 metric dimensions
You can use the following dimensions to refine the metrics listed in the previous tables.
| Dimension | Description |
| --- | --- |
| AutoScalingGroupName | This dimension filters the data you request for all instances in a specified capacity group. An *Auto Scaling group* is a collection of instances you define if you're using Auto Scaling. This dimension is available only for Amazon EC2 metrics when the instances are in such an Auto Scaling group. Available for instances with Detailed or Basic Monitoring enabled. |
| ImageId | This dimension filters the data you request for all instances running this Amazon EC2 Amazon Machine Image (AMI). Available for instances with Detailed Monitoring enabled. |
| InstanceId | This dimension filters the data you request for the identified instance only. This helps you pinpoint an exact instance from which to monitor data. |
| InstanceType | This dimension filters the data you request for all instances running with this specified instance type. This helps you categorize your data by the type of instance running. For example, you might compare data from an m1.small instance and an m1.large instance to determine which has the better business value for your application. Available for instances with Detailed Monitoring enabled. |
## Amazon EC2 usage metrics
You can use CloudWatch usage metrics to provide visibility into your account's usage of resources. Use these metrics to visualize your current service usage on CloudWatch graphs and dashboards.
Amazon EC2 usage metrics correspond to AWS service quotas. You can configure alarms that alert you when your usage approaches a service quota. For more information about CloudWatch integration with service quotas, see [AWS usage metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-Service-Quota-Integration.html) in the *Amazon CloudWatch User Guide*.
Amazon EC2 publishes the following metrics in the `AWS/Usage` namespace.
| Metric | Description |
| --- | --- |
| `ResourceCount` | The number of the specified resources running in your account. The resources are defined by the dimensions associated with the metric. The most useful statistic for this metric is `MAXIMUM`, which represents the maximum number of resources used during the 1-minute period. |
The following dimensions are used to refine the usage metrics that are published by Amazon EC2.
| Dimension | Description |
| --- | --- |
| Service | The name of the AWS service containing the resource. For Amazon EC2 usage metrics, the value for this dimension is `EC2`. |
| Type | The type of entity that is being reported. Currently, the only valid value for Amazon EC2 usage metrics is `Resource`. |
| Resource | The type of resource that is running. Currently, the only valid value for Amazon EC2 usage metrics is `vCPU`, which returns information on instances that are running. |
| Class | The class of resource being tracked. For Amazon EC2 usage metrics with `vCPU` as the value of the `Resource` dimension, the valid values are `Standard/OnDemand`, `F/OnDemand`, `G/OnDemand`, `Inf/OnDemand`, `P/OnDemand`, and `X/OnDemand`. The values for this dimension define the first letter of the instance types that are reported by the metric. For example, `Standard/OnDemand` returns information about all running instances with types that start with A, C, D, H, I, M, R, T, and Z, and `G/OnDemand` returns information about all running instances with types that start with G. |
# Install and configure the CloudWatch agent using the Amazon EC2 console to add additional metrics
| |
| --- |
| Installing and configuring the CloudWatch agent using the Amazon EC2 console is in beta for Amazon EC2 and is subject to change. |
By default, Amazon CloudWatch provides basic metrics, such as `CPUUtilization` and `NetworkIn`, for monitoring your Amazon EC2 instances. To collect additional metrics, you can install the CloudWatch agent on your EC2 instances, and then configure the agent to emit selected metrics. Instead of manually installing and configuring the CloudWatch agent on every EC2 instance, you can use the Amazon EC2 console to do this for you.
You can use the Amazon EC2 console to install the CloudWatch agent on your instances and configure the agent to emit selected metrics.
Alternatively, to complete this process manually, see [Installing the CloudWatch agent](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/install-CloudWatch-Agent-on-EC2-Instance.html) in the *Amazon CloudWatch User Guide*. For more information about the CloudWatch agent, see [Collect metrics, logs, and traces using the CloudWatch agent](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/Install-CloudWatch-Agent.html).
**Topics**
+ [
## Prerequisites
](#install-and-configure-cw-agent-prerequisites)
+ [
## How it works
](#install-and-configure-cw-agent-how-it-works)
+ [
## Costs
](#install-and-configure-cw-agent-costs)
+ [
## Install and configure the CloudWatch agent
](#install-and-configure-cw-agent-procedure)
## Prerequisites
To use Amazon EC2 to install and configure the CloudWatch agent, you must meet the user and instance prerequisites described in this section.
**Tip**
This feature is not available in all AWS Regions. If the menu item described in the installation procedure on this page does not exist in the Amazon EC2 console and you are flexible about where your instances run, try another Region. Otherwise, you can use the manual directions in the *Amazon CloudWatch User Guide* to install and configure the agent.
**User prerequisites**
To use this feature, your IAM console user or role must have the permissions required for using Amazon EC2 and the following IAM permissions:
------
#### [ JSON ]
****
```
{
"Version":"2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"ssm:GetParameter",
"ssm:PutParameter"
],
"Resource": "arn:aws:ssm:*:*:parameter/EC2-Custom-Metrics-*"
},
{
"Effect": "Allow",
"Action": [
"ssm:SendCommand",
"ssm:ListCommandInvocations",
"ssm:DescribeInstanceInformation"
],
"Resource": [
"*"
]
},
{
"Effect": "Allow",
"Action": [
"iam:GetInstanceProfile",
"iam:SimulatePrincipalPolicy"
],
"Resource": "*"
}
]
}
```
------
**Instance prerequisites**
+ Instance state: `running`
+ Supported operating system: Linux
+ AWS Systems Manager Agent (SSM Agent): Installed. Two notes about SSM Agent:
+ SSM Agent is preinstalled on some Amazon Machine Images (AMIs) provided by AWS and trusted third-parties. For information about the supported AMIs and the instructions for installing SSM Agent, see [Amazon Machine Images (AMIs) with SSM Agent preinstalled](https://docs.aws.amazon.com/systems-manager/latest/userguide/ami-preinstalled-agent.html) in the *AWS Systems Manager User Guide*.
+ If you experience issues with the SSM Agent, see [Troubleshooting SSM Agent](https://docs.aws.amazon.com/systems-manager/latest/userguide/troubleshooting-ssm-agent.html) in the *AWS Systems Manager User Guide*.
+ IAM permissions for the instance: The following AWS managed policies must be added to an IAM role that is attached to the instance:
+ [AmazonSSMManagedInstanceCore](https://docs.aws.amazon.com/aws-managed-policy/latest/reference/AmazonSSMManagedInstanceCore.html) – Enables an instance to use Systems Manager to install and configure the CloudWatch agent.
+ [CloudWatchAgentServerPolicy](https://docs.aws.amazon.com/aws-managed-policy/latest/reference/CloudWatchAgentServerPolicy.html) – Enables an instance to use the CloudWatch agent to write data to CloudWatch.
For information about how to add IAM permissions to your instance, see [Use instance profiles](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_use_switch-role-ec2_instance-profiles.html) in the *IAM User Guide*.
## How it works
Before you can use the Amazon EC2 console to install and configure the CloudWatch agent, you must make sure that your IAM user or role, and the instances on which you want to add metrics, meet certain prerequisites. Then, you can use the Amazon EC2 console to install and configure the CloudWatch agent on your selected instances.
**First meet the [prerequisites](#install-and-configure-cw-agent-prerequisites)**
+ **You need the required IAM permissions** – Before you get started, make sure that your console user or role has the required IAM permissions to use this feature.
+ **Instances** – To use the feature, your EC2 instances must be Linux instances, have the SSM Agent installed, have the required IAM permissions, and be running.
**Then you can [use the feature](#install-and-configure-cw-agent-procedure)**
1. **Select your instances** – In the Amazon EC2 console, you select the instances on which to install and configure the CloudWatch agent. You then start the process by choosing **Configure CloudWatch agent**.
1. **Validate SSM Agent** – Amazon EC2 checks that the SSM Agent is installed and started on each instance. Any instances that fail this check are excluded from the process. The SSM Agent is used for performing actions on the instance during this process.
1. **Validate IAM permissions** – Amazon EC2 checks that each instance has the required IAM permissions for this process. Any instances that fail this check are excluded from the process. The IAM permissions enable the CloudWatch agent to collect metrics from the instance and integrate with AWS Systems Manager to use the SSM Agent.
1. **Validate CloudWatch agent** – Amazon EC2 checks that the CloudWatch agent is installed and running on each instance. If any instances fail this check, Amazon EC2 offers to install and start the CloudWatch agent for you. The CloudWatch agent will collect the selected metrics on each instance once this process is completed.
1. **Select metric configuration** – You select the metrics for the CloudWatch agent to emit from your instances. Once selected, Amazon EC2 stores a configuration file in Parameter Store, where it remains until the process is completed. Amazon EC2 will delete the configuration file from Parameter Store unless the process is interrupted. Note that if you don't select a metric, but you previously added it to your instance, it will be removed from your instance when this process is completed.
1. **Update CloudWatch agent configuration** – Amazon EC2 sends the metric configuration to the CloudWatch agent. This is the last step in the process. If it succeeds, your instances can emit data for the selected metrics and Amazon EC2 deletes the configuration file from Parameter Store.
## Costs
Additional metrics that you add during this process are billed as custom metrics. For more information about CloudWatch metrics pricing, see [Amazon CloudWatch Pricing](https://aws.amazon.com/cloudwatch/pricing/).
## Install and configure the CloudWatch agent
You can use the Amazon EC2 console to install and configure the CloudWatch agent to add additional metrics.
**Note**
Every time you perform this procedure, you overwrite the existing CloudWatch agent configuration. If you don't select a metric that was selected previously, it will be removed from the instance.
**To install and configure the CloudWatch agent using the Amazon EC2 console**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instances on which to install and configure the CloudWatch agent.
1. Choose **Actions**, **Monitor and troubleshoot**, **Configure CloudWatch agent**.
1. For each step in the process, read the console text, and then choose **Next**.
1. To complete the process, in the final step, choose **Complete**.
**To update the agent configuration created by the Amazon EC2 console**
You can manually customize the configuration that the EC2 console created. For more information, see [Manually create or edit the CloudWatch agent configuration file](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch-Agent-Configuration-File-Details.html) in the *Amazon CloudWatch User Guide*.
# Statistics for CloudWatch metrics for your instances
You can get statistics for the CloudWatch metrics for your instances. *Statistics* are metric data aggregations over specified periods of time. CloudWatch provides statistics based on the metric data points provided by your custom data or provided by other services in AWS to CloudWatch. Aggregations are made using the namespace, metric name, dimensions, and the data point unit of measure, within the time period you specify. The following table describes the available statistics.
| Statistic | Description |
| --- | --- |
| Minimum | The lowest value observed during the specified period. You can use this value to determine low volumes of activity for your application. |
| Maximum | The highest value observed during the specified period. You can use this value to determine high volumes of activity for your application. |
| Sum | All values submitted for the matching metric added together. This statistic can be useful for determining the total volume of a metric. |
| Average | The value of `Sum` / `SampleCount` during the specified period. By comparing this statistic with the `Minimum` and `Maximum`, you can determine the full scope of a metric and how close the average use is to the `Minimum` and `Maximum`. This comparison helps you to know when to increase or decrease your resources as needed. |
| SampleCount | The count (number) of data points used for the statistical calculation. |
| pNN.NN | The value of the specified percentile. You can specify any percentile, using up to two decimal places (for example, p95.45). |
**Topics**
+ [
# Get statistics for a specific instance
](US_SingleMetricPerInstance.md)
+ [
# Aggregate statistics across instances
](GetSingleMetricAllDimensions.md)
+ [
# Aggregate statistics by Auto Scaling group
](GetMetricAutoScalingGroup.md)
+ [
# Aggregate statistics by AMI
](US_SingleMetricPerAMI.md)
# Get statistics for a specific instance
You can use the AWS Management Console or the AWS CLI to get statistics for a specific instance. The following examples show you how to use the AWS Management Console or the AWS CLI to determine the maximum CPU utilization of a specific EC2 instance.
**Requirements**
+ You must have the ID of the instance. You can get the instance ID using the AWS Management Console or the [describe-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-instances.html) command.
+ By default, basic monitoring is enabled, but you can enable detailed monitoring. For more information, see [Manage detailed monitoring for your EC2 instances](manage-detailed-monitoring.md).
**To display the CPU utilization for a specific instance (console)**
1. Open the CloudWatch console at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/).
1. In the navigation pane, choose **Metrics**.
1. Choose the **EC2** metric namespace.
1. Choose the **Per-Instance Metrics** dimension.
1. In the search field, enter **CPUUtilization** and press Enter. Choose the row for the specific instance, which displays a graph for the **CPUUtilization** metric for the instance. To name the graph, choose the pencil icon. To change the time range, select one of the predefined values or choose **custom**.
![\[Graph a single metric\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/metric_statistics_ec2_instance.png)
1. To change the statistic or the period for the metric, choose the **Graphed metrics** tab. Choose the column heading or an individual value, and then choose a different value.
![\[Change the statistic or period for a metric\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/metric_statistics_ec2_instance_statistic_period.png)
**To get the CPU utilization for a specific instance (AWS CLI)**
Use the following [get-metric-statistics](https://docs.aws.amazon.com/cli/latest/reference/cloudwatch/get-metric-statistics.html) command to get the **CPUUtilization** metric for the specified instance, using the specified period and time interval:
```
aws cloudwatch get-metric-statistics --namespace AWS/EC2 --metric-name CPUUtilization --period 3600 \
--statistics Maximum --dimensions Name=InstanceId,Value=i-1234567890abcdef0 \
--start-time 2022-10-18T23:18:00 --end-time 2022-10-19T23:18:00
```
The following is example output. Each value represents the maximum CPU utilization percentage for a single EC2 instance.
```
{
"Datapoints": [
{
"Timestamp": "2022-10-19T00:18:00Z",
"Maximum": 0.33000000000000002,
"Unit": "Percent"
},
{
"Timestamp": "2022-10-19T03:18:00Z",
"Maximum": 99.670000000000002,
"Unit": "Percent"
},
{
"Timestamp": "2022-10-19T07:18:00Z",
"Maximum": 0.34000000000000002,
"Unit": "Percent"
},
{
"Timestamp": "2022-10-19T12:18:00Z",
"Maximum": 0.34000000000000002,
"Unit": "Percent"
}
],
"Label": "CPUUtilization"
}
```
# Aggregate statistics across instances
Aggregate statistics are available for instances that have detailed monitoring enabled. Instances that use basic monitoring are not included in the aggregates. Before you can get statistics aggregated across instances, you must [enable detailed monitoring](manage-detailed-monitoring.md#enable-detailed-monitoring) (at an additional charge), which provides data in 1-minute periods.
Note that Amazon CloudWatch cannot aggregate data across AWS Regions. Metrics are completely separate between Regions.
This example shows you how to use detailed monitoring to get the average CPU usage for your EC2 instances. Because no dimension is specified, CloudWatch returns statistics for all dimensions in the `AWS/EC2` namespace.
**Important**
This technique for retrieving all dimensions across an AWS namespace does not work for custom namespaces that you publish to Amazon CloudWatch. With custom namespaces, you must specify the complete set of dimensions that are associated with any given data point to retrieve statistics that include the data point.
**To display average CPU utilization across your instances (console)**
1. Open the CloudWatch console at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/).
1. In the navigation pane, choose **Metrics**.
1. Choose the **EC2** namespace and then choose **Across All Instances**.
1. Choose the row that contains **CPUUtilization**, which displays a graph for the metric for all your EC2 instances. To name the graph, choose the pencil icon. To change the time range, select one of the predefined values or choose **custom**.
![\[Metrics aggregated across your EC2 instances\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/metric_aggregated_instances.png)
1. To change the statistic or the period for the metric, choose the **Graphed metrics** tab. Choose the column heading or an individual value, and then choose a different value.
**To get average CPU utilization across your instances (AWS CLI)**
Use the [get-metric-statistics](https://docs.aws.amazon.com/cli/latest/reference/cloudwatch/get-metric-statistics.html) command as follows to get the average of the **CPUUtilization** metric across your instances.
```
aws cloudwatch get-metric-statistics \
--namespace AWS/EC2 \
--metric-name CPUUtilization \
--period 3600 --statistics "Average" "SampleCount" \
--start-time 2022-10-11T23:18:00 \
--end-time 2022-10-12T23:18:00
```
The following is example output:
```
{
"Datapoints": [
{
"SampleCount": 238.0,
"Timestamp": "2022-10-12T07:18:00Z",
"Average": 0.038235294117647062,
"Unit": "Percent"
},
{
"SampleCount": 240.0,
"Timestamp": "2022-10-12T09:18:00Z",
"Average": 0.16670833333333332,
"Unit": "Percent"
},
{
"SampleCount": 238.0,
"Timestamp": "2022-10-11T23:18:00Z",
"Average": 0.041596638655462197,
"Unit": "Percent"
}
],
"Label": "CPUUtilization"
}
```
# Aggregate statistics by Auto Scaling group
You can aggregate statistics for the EC2 instances in an Auto Scaling group. Note that Amazon CloudWatch cannot aggregate data across AWS Regions. Metrics are completely separate between Regions.
This example shows you how to retrieve the total bytes written to disk for one Auto Scaling group. The total is computed for 1-minute periods for a 24-hour interval across all EC2 instances in the specified Auto Scaling group.
**To display DiskWriteBytes for the instances in an Auto Scaling group (console)**
1. Open the CloudWatch console at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/).
1. In the navigation pane, choose **Metrics**.
1. Choose the **EC2** namespace and then choose **By Auto Scaling Group**.
1. Choose the row for the **DiskWriteBytes** metric and the specific Auto Scaling group, which displays a graph for the metric for the instances in the Auto Scaling group. To name the graph, choose the pencil icon. To change the time range, select one of the predefined values or choose **custom**.
1. To change the statistic or the period for the metric, choose the **Graphed metrics** tab. Choose the column heading or an individual value, and then choose a different value.
**To display DiskWriteBytes for the instances in an Auto Scaling group (AWS CLI)**
Use the [get-metric-statistics](https://docs.aws.amazon.com/cli/latest/reference/cloudwatch/get-metric-statistics.html) command as follows.
```
aws cloudwatch get-metric-statistics --namespace AWS/EC2 --metric-name DiskWriteBytes --period 360 \
--statistics "Sum" "SampleCount" --dimensions Name=AutoScalingGroupName,Value=my-asg --start-time 2022-10-16T23:18:00 --end-time 2022-10-18T23:18:00
```
The following is example output:
```
{
"Datapoints": [
{
"SampleCount": 18.0,
"Timestamp": "2022-10-19T21:36:00Z",
"Sum": 0.0,
"Unit": "Bytes"
},
{
"SampleCount": 5.0,
"Timestamp": "2022-10-19T21:42:00Z",
"Sum": 0.0,
"Unit": "Bytes"
}
],
"Label": "DiskWriteBytes"
}
```
# Aggregate statistics by AMI
You can aggregate statistics by AMI for your instances that have detailed monitoring enabled. Instances that use basic monitoring are not included in the aggregates. Before you can get statistics aggregated across instances, you must [enable detailed monitoring](manage-detailed-monitoring.md#enable-detailed-monitoring) (at an additional charge), which provides data in 1-minute periods.
Note that Amazon CloudWatch cannot aggregate data across AWS Regions. Metrics are completely separate between Regions.
This example shows you how to determine average CPU utilization for all instances that use a specific Amazon Machine Image (AMI). The average is over 60-second time intervals for a one-day period.
**To display the average CPU utilization by AMI (console)**
1. Open the CloudWatch console at [https://console.aws.amazon.com/cloudwatch/](https://console.aws.amazon.com/cloudwatch/).
1. In the navigation pane, choose **Metrics**.
1. Choose the **EC2** namespace and then choose **By Image (AMI) Id**.
1. Choose the row for the **CPUUtilization** metric and the specific AMI, which displays a graph for the metric for the specified AMI. To name the graph, choose the pencil icon. To change the time range, select one of the predefined values or choose **custom**.
1. To change the statistic or the period for the metric, choose the **Graphed metrics** tab. Choose the column heading or an individual value, and then choose a different value.
**To get the average CPU utilization for an image ID (AWS CLI)**
Use the [get-metric-statistics](https://docs.aws.amazon.com/cli/latest/reference/cloudwatch/get-metric-statistics.html) command as follows.
```
aws cloudwatch get-metric-statistics --namespace AWS/EC2 --metric-name CPUUtilization --period 3600 \
--statistics Average --dimensions Name=ImageId,Value=ami-3c47a355 --start-time 2022-10-10T00:00:00 --end-time 2022-10-11T00:00:00
```
The following is example output. Each value represents an average CPU utilization percentage for the EC2 instances running the specified AMI.
```
{
"Datapoints": [
{
"Timestamp": "2022-10-10T07:00:00Z",
"Average": 0.041000000000000009,
"Unit": "Percent"
},
{
"Timestamp": "2022-10-10T14:00:00Z",
"Average": 0.079579831932773085,
"Unit": "Percent"
},
{
"Timestamp": "2022-10-10T06:00:00Z",
"Average": 0.036000000000000011,
"Unit": "Percent"
}
],
"Label": "CPUUtilization"
}
```
# View the monitoring graphs for your instances
After you launch an instance, you can open the Amazon EC2 console and view the monitoring graphs for the instance on the **Monitoring** tab. Each graph is based on one of the available Amazon EC2 metrics.
The following graphs are available:
+ Average CPU Utilization (Percent)
+ Average Disk Reads (Bytes)
+ Average Disk Writes (Bytes)
+ Maximum Network In (Bytes)
+ Maximum Network Out (Bytes)
+ Summary Disk Read Operations (Count)
+ Summary Disk Write Operations (Count)
+ Summary Status (Any)
+ Summary Status Instance (Count)
+ Summary Status System (Count)
For more information about the metrics and the data they provide to the graphs, see [CloudWatch metrics that are available for your instances](viewing_metrics_with_cloudwatch.md).
**Graph metrics using the CloudWatch console**
You can also use the CloudWatch console to graph metric data generated by Amazon EC2 and other AWS services. For more information, see [Graphing metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/graph_metrics.html) in the *Amazon CloudWatch User Guide*.
# Create a CloudWatch alarm for an instance
You can create a CloudWatch alarm that monitors CloudWatch metrics for one of your instances. CloudWatch will automatically send you a notification when the metric reaches a threshold you specify. You can create a CloudWatch alarm using the Amazon EC2 console, or using the more advanced options provided by the CloudWatch console.
**To create an alarm using the CloudWatch console**
For examples, see [Creating Amazon CloudWatch Alarms](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html) in the *Amazon CloudWatch User Guide*.
**To create an alarm using the Amazon EC2 console**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instance and choose **Actions**, **Monitor and troubleshoot**, **Manage CloudWatch alarms**.
1. On the **Manage CloudWatch alarms** detail page, under **Add or edit alarm**, select **Create an alarm**.
1. For **Alarm notification**, choose whether to configure Amazon Simple Notification Service (Amazon SNS) notifications. Enter an existing Amazon SNS topic or enter a name to create a new topic.
1. For **Alarm action**, choose whether to specify an action to take when the alarm is triggered. Choose an action from the list.
1. For **Alarm thresholds**, select the metric and criteria for the alarm. For example, to create an alarm that is triggered when CPU utilization reaches 80% for a 5 minute period, do the following:
1. Keep the default setting for **Group samples by** (**Average**) and **Type of data to sample** (**CPU utilization**).
1. Choose **>=** for **Alarm when** and enter **0.80** for **Percent**.
1. Enter **1** for **Consecutive period** and select **5 minutes** for **Period**.
1. (Optional) For **Sample metric data**, choose **Add to dashboard**.
1. Choose **Create**.
You can edit your CloudWatch alarm settings from the Amazon EC2 console or the CloudWatch console. If you want to delete your alarm, you can do so from the CloudWatch console. For more information, see [Edit or delete a CloudWatch alarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/Manage-CloudWatch-Alarm.html#Edit-CloudWatch-Alarm) in the *Amazon CloudWatch User Guide*.
# Create alarms that stop, terminate, reboot, or recover an instance
Using Amazon CloudWatch alarm actions, you can create alarms that automatically stop, terminate, reboot, or recover your instances. You can use the stop or terminate actions to help you save money when you no longer need an instance to be running. You can use the reboot and recover actions to automatically reboot those instances or recover them onto new hardware if a system impairment occurs.
**Note**
For Amazon CloudWatch alarms billing and pricing information, see [ CloudWatch billing and cost](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch_billing.html) in the *Amazon CloudWatch User Guide*.
The `AWSServiceRoleForCloudWatchEvents` service-linked role enables AWS to perform alarm actions on your behalf. The first time you create an alarm in the AWS Management Console, the AWS CLI, or the IAM API, CloudWatch creates the service-linked role for you.
There are a number of scenarios in which you might want to automatically stop or terminate your instance. For example, you might have instances dedicated to batch payroll processing jobs or scientific computing tasks that run for a period of time and then complete their work. Rather than letting those instances sit idle (and accrue charges), you can stop or terminate them, which can help you to save money. The main difference between using the stop and the terminate alarm actions is that you can easily start a stopped instance if you need to run it again later, and you can keep the same instance ID and root volume. However, you cannot start a terminated instance. Instead, you must launch a new instance. When an instance is stopped or terminated, data on instance store volumes is lost.
You can add the stop, terminate, reboot, or recover actions to any alarm that is set on an Amazon EC2 per-instance metric, including basic and detailed monitoring metrics provided by Amazon CloudWatch (in the `AWS/EC2` namespace), as well as any custom metrics that include the `InstanceId` dimension, as long as its value refers to a valid running Amazon EC2 instance.
**Important**
Status check alarms can temporarily enter the `INSUFFICIENT_DATA` state if there are missing metric data points. Although rare, this can happen when there is an interruption in the metric reporting systems, even when an instance is healthy. We recommend that you treat the `INSUFFICIENT_DATA` state as missing data instead of an alarm breach, especially when configuring the alarm to stop, terminate, reboot, or recover an instance.
**Console support**
You can create alarms using the Amazon EC2 console or the CloudWatch console. The procedures in this documentation use the Amazon EC2 console. For procedures that use the CloudWatch console, see [Create alarms that stop, terminate, reboot, or recover an instance](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/UsingAlarmActions.html) in the *Amazon CloudWatch User Guide*.
**Permissions**
You must have the `iam:CreateServiceLinkedRole` to create or modify an alarm that performs EC2 alarm actions. A service role is an [IAM role](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles.html) that a service assumes to perform actions on your behalf. An IAM administrator can create, modify, and delete a service role from within IAM. For more information, see [Create a role to delegate permissions to an AWS service](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_create_for-service.html) in the *IAM User Guide*.
**Topics**
+ [
## Add stop actions to Amazon CloudWatch alarms
](#AddingStopActions)
+ [
## Add terminate actions to Amazon CloudWatch alarms
](#AddingTerminateActions)
+ [
## Add reboot actions to Amazon CloudWatch alarms
](#AddingRebootActions)
+ [
## Add recover actions to Amazon CloudWatch alarms
](#AddingRecoverActions)
+ [
# Amazon CloudWatch alarm action scenarios
](AlarmActionScenarios.md)
## Add stop actions to Amazon CloudWatch alarms
You can create an alarm that stops an Amazon EC2 instance when a certain threshold has been met. For example, you may run development or test instances and occasionally forget to shut them off. You can create an alarm that is triggered when the average CPU utilization percentage has been lower than 10 percent for 24 hours, signaling that it is idle and no longer in use. You can adjust the threshold, duration, and period to suit your needs, plus you can add an Amazon Simple Notification Service (Amazon SNS) notification so that you receive an email when the alarm is triggered.
Instances that use an Amazon EBS volume as the root volume can be stopped or terminated, whereas instances that use the instance store as the root volume can only be terminated. Data on instance store volumes is lost when the instance is terminated or stopped.
**To create an alarm to stop an idle instance (Amazon EC2 console)**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instance and choose **Actions**, **Monitor and troubleshoot**, **Manage CloudWatch alarms**.
Alternatively, you can choose the plus sign ( ![\[Plus sign.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/add-plus.png) ) in the **Alarm status** column.
1. On the **Manage CloudWatch alarms** page, do the following:
1. Choose **Create an alarm**.
1. To receive an email when the alarm is triggered, for **Alarm notification**, choose an existing Amazon SNS topic. You first need to create an Amazon SNS topic using the Amazon SNS console. For more information, see [Using Amazon SNS for application-to-person (A2P) messaging](https://docs.aws.amazon.com/sns/latest/dg/sns-user-notifications.html) in the *Amazon Simple Notification Service Developer Guide*.
1. Toggle on **Alarm action**, and choose **Stop**.
1. For **Group samples by** and **Type of data to sample**, choose a statistic and a metric. In this example, choose **Average** and **CPU utilization**.
1. For **Alarm When** and **Percent**, specify the metric threshold. In this example, specify **<=** and **10** percent.
1. For **Consecutive period** and **Period**, specify the evaluation period for the alarm. In this example, specify **1** consecutive period of **5 Minutes**.
1. Amazon CloudWatch automatically creates an alarm name for you. To change the name, for **Alarm name**, enter a new name. Alarm names must contain only ASCII characters.
**Note**
You can adjust the alarm configuration based on your own requirements before creating the alarm, or you can edit them later. This includes the metric, threshold, duration, action, and notification settings. However, after you create an alarm, you cannot edit its name later.
1. Choose **Create**.
## Add terminate actions to Amazon CloudWatch alarms
You can create an alarm that terminates an EC2 instance automatically when a certain threshold has been met (as long as termination protection is not enabled for the instance). For example, you might want to terminate an instance when it has completed its work, and you don’t need the instance again. If you might want to use the instance later, you should stop the instance instead of terminating it. Data on instance store volumes is lost when the instance is terminated. For information about enabling and disabling termination protection for an instance, see [Change instance termination protection](Using_ChangingDisableAPITermination.md).
**To create an alarm to terminate an idle instance (Amazon EC2 console)**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instance and choose **Actions**, **Monitor and troubleshoot**, **Manage CloudWatch alarms**.
Alternatively, you can choose the plus sign ( ![\[Plus sign.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/add-plus.png) ) in the **Alarm status** column.
1. On the **Manage CloudWatch alarms** page, do the following:
1. Choose **Create an alarm**.
1. To receive an email when the alarm is triggered, for **Alarm notification**, choose an existing Amazon SNS topic. You first need to create an Amazon SNS topic using the Amazon SNS console. For more information, see [Using Amazon SNS for application-to-person (A2P) messaging](https://docs.aws.amazon.com/sns/latest/dg/sns-user-notifications.html) in the *Amazon Simple Notification Service Developer Guide*.
1. Toggle on **Alarm action**, and choose **Terminate**.
1. For **Group samples by** and **Type of data to sample**, choose a statistic and a metric. In this example, choose **Average** and **CPU utilization**.
1. For **Alarm When** and **Percent**, specify the metric threshold. In this example, specify **=>** and **10** percent.
1. For **Consecutive period** and **Period**, specify the evaluation period for the alarm. In this example, specify **24** consecutive periods of **1 Hour**.
1. Amazon CloudWatch automatically creates an alarm name for you. To change the name, for **Alarm name**, enter a new name. Alarm names must contain only ASCII characters.
**Note**
You can adjust the alarm configuration based on your own requirements before creating the alarm, or you can edit them later. This includes the metric, threshold, duration, action, and notification settings. However, after you create an alarm, you cannot edit its name later.
1. Choose **Create**.
## Add reboot actions to Amazon CloudWatch alarms
You can create an Amazon CloudWatch alarm that monitors an Amazon EC2 instance and automatically reboots the instance. The reboot alarm action is recommended for Instance Health Check failures (as opposed to the recover alarm action, which is suited for System Health Check failures). An instance reboot is equivalent to an operating system reboot. In most cases, it takes only a few minutes to reboot your instance. When you reboot an instance, it remains on the same physical host, so your instance keeps its public DNS name, private IP address, and any data on its instance store volumes.
Rebooting an instance doesn't start a new instance billing period (with a minimum one-minute charge), unlike stopping and restarting your instance. Data on instance store volumes is retained when the instance is rebooted. The instance store volumes must be re-mounted into the filesystem after a reboot. For more information, see [Reboot your Amazon EC2 instance](ec2-instance-reboot.md).
**Important**
To avoid a race condition between the reboot and recover actions, avoid setting the same number of evaluation periods for a reboot alarm and a recover alarm. We recommend that you set reboot alarms to three evaluation periods of one minute each. For more information, see [Evaluating an alarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html#alarm-evaluation) in the *Amazon CloudWatch User Guide*.
**To create an alarm to reboot an instance (Amazon EC2 console)**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instance and choose **Actions**, **Monitor and troubleshoot**, **Manage CloudWatch alarms**.
Alternatively, you can choose the plus sign ( ![\[Plus sign.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/add-plus.png) ) in the **Alarm status** column.
1. On the **Manage CloudWatch alarms** page, do the following:
1. Choose **Create an alarm**.
1. To receive an email when the alarm is triggered, for **Alarm notification**, choose an existing Amazon SNS topic. You first need to create an Amazon SNS topic using the Amazon SNS console. For more information, see [Using Amazon SNS for application-to-person (A2P) messaging](https://docs.aws.amazon.com/sns/latest/dg/sns-user-notifications.html) in the *Amazon Simple Notification Service Developer Guide*.
1. Toggle on **Alarm action**, and choose **Reboot**.
1. For **Group samples by** and **Type of data to sample**, choose a statistic and a metric. In this example, choose **Average** and **Status check failed: instance**.
1. For **Consecutive period** and **Period**, specify the evaluation period for the alarm. In this example, enter **3** consecutive periods of **1 Minute**. If **1 Minute is disabled**, you must [enable detailed monitoring](manage-detailed-monitoring.md#enable-detailed-monitoring), or you can choose **5 Minutes** instead.
1. Amazon CloudWatch automatically creates an alarm name for you. To change the name, for **Alarm name**, enter a new name. Alarm names must contain only ASCII characters.
1. Choose **Create**.
## Add recover actions to Amazon CloudWatch alarms
You can create an Amazon CloudWatch alarm that monitors an Amazon EC2 instance. If the instance becomes impaired due to an underlying hardware failure or a problem that requires AWS involvement to repair, you can automatically recover the instance. Terminated instances cannot be recovered. A recovered instance is identical to the original instance, including the instance ID, private IP addresses, Elastic IP addresses, and all instance metadata.
CloudWatch prevents you from adding a recovery action to an alarm that is on an instance which does not support recovery actions.
When the `StatusCheckFailed_System` alarm is triggered, and the recover action is initiated, you are notified by the Amazon SNS topic that you chose when you created the alarm and associated the recover action. During instance recovery, the instance is migrated during an instance reboot, and any data that is in-memory is lost. When the process is complete, information is published to the SNS topic you've configured for the alarm. Anyone who is subscribed to this SNS topic receives an email notification that includes the status of the recovery attempt and any further instructions. You notice an instance reboot on the recovered instance.
**Note**
The recover action can be used only with `StatusCheckFailed_System`, not with `StatusCheckFailed_Instance`.
The following problems can cause system status checks to fail:
+ Loss of network connectivity
+ Loss of system power
+ Software issues on the physical host
+ Hardware issues on the physical host that impact network reachability
The recover action is supported only on instances that meet certain characteristics. For more information, see [Automatic instance recovery](ec2-instance-recover.md).
If your instance has a public IP address, it retains the public IP address after recovery.
**Important**
To avoid a race condition between the reboot and recover actions, avoid setting the same number of evaluation periods for a reboot alarm and a recover alarm. We recommend that you set recover alarms to two evaluation periods of one minute each. For more information, see [Evaluating an alarm](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/AlarmThatSendsEmail.html#alarm-evaluation) in the *Amazon CloudWatch User Guide*.
**To create an alarm to recover an instance (Amazon EC2 console)**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. In the navigation pane, choose **Instances**.
1. Select the instance and choose **Actions**, **Monitor and troubleshoot**, **Manage CloudWatch alarms**.
Alternatively, you can choose the plus sign ( ![\[Plus sign.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/add-plus.png) ) in the **Alarm status** column.
1. On the **Manage CloudWatch alarms** page, do the following:
1. Choose **Create an alarm**.
1. To receive an email when the alarm is triggered, for **Alarm notification**, choose an existing Amazon SNS topic. You first need to create an Amazon SNS topic using the Amazon SNS console. For more information, see [Using Amazon SNS for application-to-person (A2P) messaging](https://docs.aws.amazon.com/sns/latest/dg/sns-user-notifications.html) in the *Amazon Simple Notification Service Developer Guide*.
**Note**
Users must subscribe to the specified SNS topic to receive email notifications when the alarm is triggered. The AWS account root user always receives email notifications when automatic instance recovery actions occur, even if an SNS topic is not specified or the root user is not subscribed to the specified SNS topic.
1. Toggle on **Alarm action**, and choose **Recover**.
1. For **Group samples by** and **Type of data to sample**, choose a statistic and a metric. In this example, choose **Average** and **Status check failed: system**.
1. For **Consecutive period** and **Period**, specify the evaluation period for the alarm. In this example, enter **2** consecutive periods of **1 Minute**. If **1 Minute is disabled**, you must [enable detailed monitoring](manage-detailed-monitoring.md#enable-detailed-monitoring), or you can choose **5 Minutes** instead.
1. Amazon CloudWatch automatically creates an alarm name for you. To change the name, for **Alarm name**, enter a new name. Alarm names must contain only ASCII characters.
1. Choose **Create**.
# Amazon CloudWatch alarm action scenarios
You can use the Amazon EC2 console to create alarm actions that stop or terminate an Amazon EC2 instance when certain conditions are met. In the following screen capture of the console page where you set the alarm actions, we've numbered the settings. We've also numbered the settings in the scenarios that follow, to help you create the appropriate actions.
![\[Manage Cloudwatch alarms page.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/manage-cloudwatch-alarms.png)
## Scenario 1: Stop idle development and test instances
Create an alarm that stops an instance used for software development or testing when it has been idle for at least an hour.
| Setting | Value |
| --- | --- |
| 1 | Stop |
| 2 | Maximum |
| 3 | CPU Utilization |
| 4 | <= |
| 5 | 10% |
| 6 | 1 |
| 7 | 1 Hour |
## Scenario 2: Stop idle instances
Create an alarm that stops an instance and sends an email when the instance has been idle for 24 hours.
| Setting | Value |
| --- | --- |
| 1 | Stop and email |
| 2 | Average |
| 3 | CPU Utilization |
| 4 | <= |
| 5 | 5% |
| 6 | 24 |
| 7 | 1 Hour |
## Scenario 3: Send email about web servers with unusually high traffic
Create an alarm that sends email when an instance exceeds 10 GB of outbound network traffic per day.
| Setting | Value |
| --- | --- |
| 1 | Email |
| 2 | Sum |
| 3 | Network Out |
| 4 | > |
| 5 | 10 GB |
| 6 | 24 |
| 7 | 1 Hour |
## Scenario 4: Stop web servers with unusually high traffic
Create an alarm that stops an instance and send a text message (SMS) if outbound traffic exceeds 1 GB per hour.
| Setting | Value |
| --- | --- |
| 1 | Stop and send SMS |
| 2 | Sum |
| 3 | Network Out |
| 4 | > |
| 5 | 1 GB |
| 6 | 1 |
| 7 | 1 Hour |
## Scenario 5: Stop an impaired instance
Create an alarm that stops an instance that fails three consecutive status checks (performed at 5-minute intervals).
| Setting | Value |
| --- | --- |
| 1 | Stop |
| 2 | Average |
| 3 | Status Check Failed: System |
| 4 | - |
| 5 | - |
| 6 | 1 |
| 7 | 15 Minutes |
## Scenario 6: Terminate instances when batch processing jobs are complete
Create an alarm that terminates an instance that runs batch jobs when it is no longer sending results data.
| Setting | Value |
| --- | --- |
| 1 | Terminate |
| 2 | Maximum |
| 3 | Network Out |
| 4 | <= |
| 5 | 100,000 bytes |
| 6 | 1 |
| 7 | 5 Minutes |