AWS Systems Manager
User Guide

Working with Parameter Versions

When you initially create a parameter, Parameter Store assigns version 1 to that parameter. When you edit a parameter, Parameter Store automatically iterates the version number by 1. You can specify a parameter name and a specific version number in API calls and SSM documents. If you don't specify a version number, the system automatically uses the latest version.

Parameter versions provide a layer of protection in the event that a parameter is accidentally changed. You can view the details, including the values, of all versions. You can also use parameter versions to see how many times a parameter changed over a period of time.

You can reference specific parameter versions, including older versions, in commands, API calls, and SSM documents by using the following format: {{ssm:parameter_name:version}}. Here is an example for a parameter named RunCommand specified in an SSM document:

{ "schemaVersion":"1.2", "description":"Run a shell script or specify the commands to run.", "parameters":{ "commands":{ "type":"StringList", "description":"(Required) Specify a shell script or a command to run.", "minItems":1, "displayType":"textarea", "default":"{{ssm:RunCommand:2}}" }, "executionTimeout":{ "type":"String", "default":"3600", "description":"(Optional) The time in seconds for a command to complete before it is considered to have failed. Default is 3600 (1 hour). Maximum is 172800 (48 hours).", "allowedPattern":"([1-9][0-9]{0,3})|(1[0-9]{1,4})|(2[0-7][0-9]{1,3})|(28[0-7][0-9]{1,2})|(28800)" } }, "runtimeConfig":{ "aws:runShellScript":{ "properties":[ { "id":"", "runCommand":"{{ commands }}", "timeoutSeconds":"{{ executionTimeout }}" } ] } } }

The following procedures show you how to edit a parameter and then verify that a new version was created.

Create a New Parameter Version (Console)

You can use the Amazon EC2 console or AWS Systems Manager console to create a new version of a parameter.

To create a new parameter version

  1. Open the AWS Systems Manager console at

  2. In the navigation pane, choose Parameter Store.


    If the AWS Systems Manager home page opens first, choose the menu icon ( ) to open the navigation pane, and then choose Parameter Store.

  3. Choose the name of a parameter that you created earlier. For information about creating a new parameter, see Creating Systems Manager Parameters.


    Parameters are only available in the Region where they were created. If you don't see a parameter that you want to update, then verify your Region.

  4. Choose Edit.

  5. In the Value box, type a new value, and then choose Save changes.

  6. In the parameters list, choose the name of the parameter you just updated, and then view the History tab. On the Overview tab, verify that the version number incremented by 1, and verify the new value.