• The AWS Systems Manager CloudWatch Dashboard will no longer be available after April 30, 2026. Customers can continue to use Amazon CloudWatch console to view, create, and manage their Amazon CloudWatch dashboards, just as they do today. For more information, see [Amazon CloudWatch Dashboard documentation](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/CloudWatch_Dashboards.html). 

# Automation system variables
<a name="automation-variables"></a>

AWS Systems Manager Automation runbooks use the following variables. For an example of how these variables are used, view the JSON source of the `AWS-UpdateWindowsAmi` runbook. 

**To view the JSON source of the `AWS-UpdateWindowsAmi` runbook**

1. Open the AWS Systems Manager console at [https://console.aws.amazon.com/systems-manager/](https://console.aws.amazon.com/systems-manager/).

1. In the navigation pane, choose **Documents**.

1. In the document list, use either the Search bar or the numbers to the right of the Search bar to choose the runbook `AWS-UpdateWindowsAmi`.

1. Choose the **Content** tab. 

**System variables**  
Automation runbooks support the following system variables.


****  

| Variable | Details | 
| --- | --- | 
|  `global:ACCOUNT_ID`  |  The AWS account ID of the user or role in which Automation runs.  | 
|  `global:DATE`  |  The date (at run time) in the format yyyy-MM-dd.  | 
|  `global:DATE_TIME`  |  The date and time (at run time) in the format yyyy-MM-dd\$1HH.mm.ss.  | 
|  `global:AWS_PARTITION`  |  The partition that the resource is in. For standard AWS Regions, the partition is `aws`. For resources in other partitions, the partition is `aws-partitionname`. For example, the partition for resources in the AWS GovCloud (US-West) Region is `aws-us-gov`.  | 
|  `global:REGION`  |  The Region that the runbook is run in. For example, us-east-2.  | 

**Automation variables**  
Automation runbooks support the following automation variables.


****  

| Variable | Details | 
| --- | --- | 
|  `automation:EXECUTION_ID`  |  The unique identifier assigned to the current automation. For example, `1a2b3c-1a2b3c-1a2b3c-1a2b3c1a2b3c1a2b3c`.  | 

**Topics**
+ [Terminology](#automation-terms)
+ [Supported scenarios](#automation-variables-support)
+ [Unsupported scenarios](#automation-variables-unsupported)

## Terminology
<a name="automation-terms"></a>

The following terms describe how variables and parameters are resolved.


****  

| Term | Definition | Example | 
| --- | --- | --- | 
|  Constant ARN  |  A valid Amazon Resource Name (ARN) without variables.  |  `arn:aws:iam::123456789012:role/roleName`  | 
|  Runbook parameter  |  A parameter defined at the runbook level (for example, `instanceId`). The parameter is used in a basic string replace. Its value is supplied at Start Execution time.  |  <pre>{ <br />   "description": "Create Image Demo",<br />   "version": "0.3",<br />   "assumeRole": "Your_Automation_Assume_Role_ARN",<br />   "parameters":{ <br />      "instanceId": { <br />         "type": "String",<br />         "description": "Instance to create image from"<br />   }<br />}</pre>  | 
|  System variable  |  A general variable substituted into the runbook when any part of the runbook is evaluated.  |  <pre>"activities": [ <br />   { <br />      "id": "copyImage",<br />      "activityType": "AWS-CopyImage",<br />      "maxAttempts": 1,<br />      "onFailure": "Continue",<br />      "inputs": { <br />         "ImageName": "{{imageName}}",<br />         "SourceImageId": "{{sourceImageId}}",<br />         "SourceRegion": "{{sourceRegion}}",<br />         "Encrypted": true,<br />         "ImageDescription": "Test CopyImage Description created on {{global:DATE}}"<br />      }<br />   }<br />]</pre>  | 
|  Automation variable  |  A variable relating to the automation substituted into the runbook when any part of the runbook is evaluated.  |  <pre>{ <br />   "name": "runFixedCmds",<br />   "action": "aws:runCommand",<br />   "maxAttempts": 1,<br />   "onFailure": "Continue",<br />   "inputs": { <br />      "DocumentName": "AWS-RunPowerShellScript",<br />      "InstanceIds": [ <br />         "{{LaunchInstance.InstanceIds}}"<br />      ],<br />      "Parameters": { <br />         "commands": [ <br />            "dir",<br />            "date",<br />            "“{{outputFormat}}” -f “left”,”right”,”{{global:DATE}}”,”{{automation:EXECUTION_ID}}”<br />         ]<br />      }<br />   }<br />}</pre>  | 
|  Systems Manager Parameter  |  A variable defined within AWS Systems Manager Parameter Store. It can't be directly referenced in step input. Permissions might be required to access the parameter.  |  <pre><br />description: Launch new Windows test instance<br />schemaVersion: '0.3'<br />assumeRole: '{{AutomationAssumeRole}}'<br />parameters:<br />  AutomationAssumeRole:<br />    type: String<br />    default: ''<br />    description: >-<br />      (Required) The ARN of the role that allows Automation to perform the<br />      actions on your behalf. If no role is specified, Systems Manager<br />      Automation uses your IAM permissions to run this runbook.<br />  LatestAmi:<br />    type: String<br />    default: >-<br />      {{ssm:/aws/service/ami-windows-latest/Windows_Server-2016-English-Full-Base}}<br />    description: The latest Windows Server 2016 AMI queried from the public parameter.<br />mainSteps:<br />  - name: launchInstance<br />    action: 'aws:runInstances'<br />    maxAttempts: 3<br />    timeoutSeconds: 1200<br />    onFailure: Abort<br />    inputs:<br />      ImageId: '{{LatestAmi}}'<br />...</pre>  | 

## Supported scenarios
<a name="automation-variables-support"></a>


****  

| Scenario | Comments | Example | 
| --- | --- | --- | 
|  Constant ARN `assumeRole` at creation.  |  An authorization check is performed to verify that the calling user is permitted to pass the given `assumeRole`.  |  <pre>{<br />  "description": "Test all Automation resolvable parameters",<br />  "schemaVersion": "0.3",<br />  "assumeRole": "arn:aws:iam::123456789012:role/roleName",<br />  "parameters": { <br />  ...</pre>  | 
|  Runbook parameter supplied for `AssumeRole` when the automation is started.  |  Must be defined in the parameter list of the runbook.  |  <pre>{<br />  "description": "Test all Automation resolvable parameters",<br />  "schemaVersion": "0.3",<br />  "assumeRole": "{{dynamicARN}}",<br />  "parameters": {<br /> ...</pre>  | 
|  Value supplied for runbook parameter at start.  |  Customer supplies the value to use for a parameter. Any inputs supplied at start time need to be defined in the parameter list of the runbook.  |  <pre>...<br />"parameters": {<br />    "amiId": {<br />      "type": "String",<br />      "default": "ami-12345678",<br />      "description": "list of commands to run as part of first step"<br />    },<br />...</pre> Inputs to Start Automation Execution include : `{"amiId" : ["ami-12345678"] }`  | 
|  Systems Manager Parameter referenced within runbook content.  |  The variable exists within the customer's account, or is a publicly accessibly parameter, and the `AssumeRole` for the runbook has access to the variable. A check is performed at create time to confirm the `AssumeRole` has access. The parameter can't be directly referenced in step input.  |  <pre><br />...<br />parameters:<br />    LatestAmi:<br />    type: String<br />    default: >-<br />      {{ssm:/aws/service/ami-windows-latest/Windows_Server-2016-English-Full-Base}}<br />    description: The latest Windows Server 2016 AMI queried from the public parameter.<br />mainSteps:<br />  - name: launchInstance<br />    action: 'aws:runInstances'<br />    maxAttempts: 3<br />    timeoutSeconds: 1200<br />    onFailure: Abort<br />    inputs:<br />      ImageId: '{{LatestAmi}}'<br />...</pre>  | 
|  System variable referenced within step definition  |  A system variable is substituted into the runbook when the automation is started. The value injected into the runbook is relative to when the substitution occurs. That is, the value of a time variable injected at step 1 is different from the value injected at step 3 because of the time it takes to run the steps between. System variables don't need to be set in the parameter list of the runbook.  |  <pre>...<br />  "mainSteps": [<br />    {<br />      "name": "RunSomeCommands",<br />      "action": "aws:runCommand",<br />      "maxAttempts": 1,<br />      "onFailure": "Continue",<br />      "inputs": {<br />        "DocumentName": "AWS:RunPowerShell",<br />        "InstanceIds": ["{{LaunchInstance.InstanceIds}}"],<br />        "Parameters": {<br />            "commands" : [<br />                "echo {The time is now {{global:DATE_TIME}}}"<br />            ]<br />        }<br />    }<br />}, ... </pre>  | 
|  Automation variable referenced within step definition.  |  Automation variables don't need to be set in the parameter list of the runbook. The only supported Automation variable is **automation:EXECUTION\$1ID**.  |  <pre>...<br />"mainSteps": [<br />    {<br />      "name": "invokeLambdaFunction",<br />      "action": "aws:invokeLambdaFunction",<br />      "maxAttempts": 1,<br />      "onFailure": "Continue",<br />      "inputs": {<br />        "FunctionName": "Hello-World-LambdaFunction",<br /><br />"Payload" : "{ "executionId" : "{{automation:EXECUTION_ID}}" }"<br />      }<br />    }<br />... </pre>  | 
|  Refer to output from previous step within next step definition.  |  This is parameter redirection. The output of a previous step is referenced using the syntax `{{stepName.OutputName}}`. This syntax can't be used by the customer for runbook parameters. This is resolved when the referring step runs. The parameter isn't listed in the parameters of the runbook.  |  <pre>...<br />"mainSteps": [<br />    {<br />      "name": "LaunchInstance",<br />      "action": "aws:runInstances",<br />      "maxAttempts": 1,<br />      "onFailure": "Continue",<br />      "inputs": {<br />        "ImageId": "{{amiId}}",<br />        "MinInstanceCount": 1,<br />        "MaxInstanceCount": 2<br />      }<br />    },<br />    {<br />      "name":"changeState",<br />      "action": "aws:changeInstanceState",<br />      "maxAttempts": 1,<br />      "onFailure": "Continue",<br />      "inputs": {<br />        "InstanceIds": ["{{LaunchInstance.InstanceIds}}"],<br />        "DesiredState": "terminated"<br />      }<br />    }<br /><br />... </pre>  | 

## Unsupported scenarios
<a name="automation-variables-unsupported"></a>


****  

| Scenario | Comment | Example | 
| --- | --- | --- | 
|  Systems Manager Parameter supplied for `assumeRole` at create  |  Not supported.  |  <pre>...<br /><br />{<br />  "description": "Test all Automation resolvable parameters",<br />  "schemaVersion": "0.3",<br />  "assumeRole": "{{ssm:administratorRoleARN}}",<br />  "parameters": {<br /><br />... </pre>  | 
|  Systems Manager Parameter directly referenced in step input.  |  Returns `InvalidDocumentContent` exception at create time.  |  <pre><br />...<br />mainSteps:<br />  - name: launchInstance<br />    action: 'aws:runInstances'<br />    maxAttempts: 3<br />    timeoutSeconds: 1200<br />    onFailure: Abort<br />    inputs:<br />      ImageId: '{{ssm:/aws/service/ami-windows-latest/Windows_Server-2016-English-Full-Base}}'<br />...</pre>  | 
|  Variable step definition  |  The definition of a step in the runbook is constructed by variables.  |  <pre>...<br /><br />"mainSteps": [<br />    {<br />      "name": "LaunchInstance",<br />      "action": "aws:runInstances",<br />      "{{attemptModel}}": 1,<br />      "onFailure": "Continue",<br />      "inputs": {<br />        "ImageId": "ami-12345678",<br />        "MinInstanceCount": 1,<br />        "MaxInstanceCount": 2<br />      }<br /><br />...<br /><br />User supplies input : { "attemptModel" : "minAttempts" } </pre>  | 
|  Cross referencing runbook parameters  |  The user supplies an input parameter at start time, which is a reference to another parameter in the runbook.  |  <pre>...<br />"parameters": {<br />    "amiId": {<br />      "type": "String",<br />      "default": "ami-7f2e6015",<br />      "description": "list of commands to run as part of first step"<br />    },<br />    "alternateAmiId": {<br />      "type": "String",<br />      "description": "The alternate AMI to try if this first fails".<br /><br />"default" : "{{amiId}}"<br />    },<br /><br />... </pre>  | 
|  Multi-level expansion  |  The runbook defines a variable that evaluates to the name of a variable. This sits within the variable delimiters (that is *\$1\$1 \$1\$1*) and is expanded to the value of that variable/parameter.  |  <pre>...<br />  "parameters": {<br />    "firstParameter": {<br />      "type": "String",<br />      "default": "param2",<br />      "description": "The parameter to reference"<br />    },<br />    "secondParameter": {<br />      "type": "String",<br />      "default" : "echo {Hello world}",<br />      "description": "What to run"<br />    }<br />  },<br />  "mainSteps": [{<br />      "name": "runFixedCmds",<br />      "action": "aws:runCommand",<br />      "maxAttempts": 1,<br />      "onFailure": "Continue",<br />      "inputs": {<br />        "DocumentName": "AWS-RunPowerShellScript",<br /><br />"InstanceIds" : "{{LaunchInstance.InstanceIds}}",<br />        "Parameters": {<br />          "commands": [ "{{ {{firstParameter}} }}"]<br /><br />}<br /><br />...<br /><br />Note: The customer intention here would be to run a command of "echo {Hello world}" </pre>  | 
|  Referencing output from a runbook step that is a different variable type  |  The user references the output from a preceding runbook step within a subsequent step. The output is a variable type that doesn't meet the requirements of the action in the subsequent step.  |  <pre>...<br />mainSteps:<br />- name: getImageId<br />  action: aws:executeAwsApi<br />  inputs:<br />    Service: ec2<br />    Api: DescribeImages<br />    Filters:  <br />    - Name: "name"<br />      Values: <br />      - "{{ImageName}}"<br />  outputs:<br />  - Name: ImageIdList<br />    Selector: "$.Images"<br />    Type: "StringList"<br />- name: copyMyImages<br />  action: aws:copyImage<br />  maxAttempts: 3<br />  onFailure: Abort<br />  inputs:<br />    SourceImageId: {{getImageId.ImageIdList}}<br />    SourceRegion: ap-northeast-2<br />    ImageName: Encrypted Copies of LAMP base AMI in ap-northeast-2<br />    Encrypted: true <br />... <br />Note: You must provide the type required by the Automation action. <br />In this case, aws:copyImage requires a "String" type variable but the preceding step outputs a "StringList" type variable.<br />                                        </pre>  |