Find an AMI that meets the requirements for your EC2 instance

You can find AMIs using the Amazon EC2 console. You can select from the list of AMIs when you use the launch instance wizard to launch an instance, or you can search through all available AMIs using the Images page.

You can use the describe-images command to list only the AMIs that match your requirements. After locating an AMI that matches your requirements, make note of its ID so that you can use it to launch instances. For more information, see Launch your instance in the AWS Command Line Interface User Guide.

The describe-images command supports filtering parameters. For example, use the --owners parameter to display public AMIs owned by Amazon.

aws ec2 describe-images --owners amazon

You can add the following filter to the previous command to display only Windows AMIs.

--filters "Name=platform,Values=windows"

You can add the following filter to the previous command to display only AMIs backed by Amazon EBS.

--filters "Name=root-device-type,Values=ebs"

You can use PowerShell cmdlets to list only the Windows AMIs that match your requirements. For information and examples, see Find an Amazon Machine Image Using Windows PowerShell in the AWS Tools for Windows PowerShell User Guide.

After locating an AMI that matches your requirements, make note of its ID so that you can use it to launch instances. For more information, see Launch an Amazon EC2 Instance Using Windows PowerShell in the AWS Tools for Windows PowerShell User Guide.

When you launch an instance using the EC2 launch instance wizard in the Amazon EC2 console, you can either select an AMI from the list (described in Find an AMI using the Amazon EC2 console), or you can select an AWS Systems Manager parameter that points to an AMI ID (described in this section). If you use automation code to launch your instances, you can specify the Systems Manager parameter instead of the AMI ID.

A Systems Manager parameter is a customer-defined key-value pair that you can create in Systems Manager Parameter Store. The Parameter Store provides a central store to externalize your application configuration values. For more information, see AWS Systems Manager Parameter Store in the AWS Systems Manager User Guide.

When you create a parameter that points to an AMI ID, make sure that you specify the data type as aws:ec2:image. Specifying this data type ensures that when the parameter is created or modified, the parameter value is validated as an AMI ID. For more information, see Native parameter support for Amazon Machine Image IDs in the AWS Systems Manager User Guide.

Use cases

When you use Systems Manager parameters to point to AMI IDs, it is easier for your users to select the correct AMI when launching instances. Systems Manager parameters can also simplify the maintenance of automation code.

Easier for users

If you require instances to be launched using a specific AMI, and the AMI is regularly updated, we recommend that you require your users to select a Systems Manager parameter to find the AMI. Requiring your users to select a Systems Manager parameter ensures that the latest AMI is used to launch instances.

For example, every month in your organization you might create a new version of your AMI that has the latest operating system and application patches. You also require your users to launch instances using the latest version of your AMI. To ensure that your users use the latest version, you can create a Systems Manager parameter (for example, golden-ami) that points to the correct AMI ID. Each time a new version of the AMI is created, you update the AMI ID value in the parameter so that it always points to the latest AMI. Your users don't have to know about the periodic updates to the AMI because they continue to select the same Systems Manager parameter each time. Using a Systems Manager parameter for your AMI makes it easier for them to select the correct AMI for an instance launch.

Simplify automation code maintenance

If you use automation code to launch your instances, you can specify the Systems Manager parameter instead of the AMI ID. If a new version of the AMI is created, you can change the AMI ID value in the parameter so that it points to the latest AMI. The automation code that references the parameter doesn’t have to be modified each time a new version of the AMI is created. This simplifies the maintenance of the automation and helps to drive down deployment costs.

Permissions

If you use Systems Manager parameters that point to AMI IDs in the launch instance wizard, you must add the following permissions to your IAM policy:

You can also restrict access to specific Systems Manager parameters. For more information and example IAM policies, see Example: Use the EC2 launch instance wizard.

Limitations

AMIs and Systems Manager parameters are Region specific. To use the same Systems Manager parameter name across Regions, create a Systems Manager parameter in each Region with the same name (for example, golden-ami). In each Region, point the Systems Manager parameter to an AMI in that Region.

Launch an instance using a Systems Manager parameter

You can launch an instance using the console or the AWS CLI. Instead of specifying an AMI ID, you can specify an AWS Systems Manager parameter that points to an AMI ID.

For more information about launching an instance using the launch instance wizard, see Launch an EC2 instance using the launch instance wizard in the console.

To launch an instance using an AWS Systems Manager parameter instead of an AMI ID (AWS CLI)

The following example uses the Systems Manager parameter golden-ami to launch an m5.xlarge instance. The parameter points to an AMI ID.

To specify the parameter in the command, use the following syntax: resolve:ssm:/parameter-name, where resolve:ssm is the standard prefix and parameter-name is the unique parameter name. Note that the parameter name is case-sensitive. Backslashes for the parameter name are only necessary when the parameter is part of a hierarchy, for example, /amis/production/golden-ami. You can omit the backslash if the parameter is not part of a hierarchy.

In this example, the --count and --security-group parameters are not included. For --count, the default is 1. If you have a default VPC and a default security group, they are used.

aws ec2 run-instances 
    --image-id resolve:ssm:/golden-ami 
    --instance-type m5.xlarge 
    ...

To launch an instance using a specific version of an AWS Systems Manager parameter (AWS CLI)

Systems Manager parameters have version support. Each iteration of a parameter is assigned a unique version number. You can reference the version of the parameter as follows resolve:ssm:parameter-name:version, where version is the unique version number. By default, the latest version of the parameter is used when no version is specified.

The following example uses version 2 of the parameter.

In this example, the --count and --security-group parameters are not included. For --count, the default is 1 If you have a default VPC and a default security group, they are used.

aws ec2 run-instances 
    --image-id resolve:ssm:/golden-ami:2 
    --instance-type m5.xlarge 
    ...

To launch an instance using a public parameter provided by AWS

Systems Manager provides public parameters for public AMIs provided by AWS. You can use the public parameters when launching instances to ensure that you're using the latest AMIs.

For more information, see Find the latest AMIs using a Systems Manager public parameter.

AWS Systems Manager provides public parameters for public AMIs maintained by AWS. You can use the public parameters when launching instances to ensure that you're using the latest AMIs. For example, the public parameter /aws/service/ami-amazon-linux-latest/al2023-ami-kernel-default-arm64 is available in all Regions and always points to the latest version of the Amazon Linux 2023 AMI for arm64 architecture in a given Region.

The public parameters are available from the following paths:

To view a list of all the Linux or Windows AMIs in the current AWS Region

Use the following get-parameters-by-path command to view a list of all the Linux or Windows AMIs in the current AWS Region. The value for the --path parameter is different for Linux and Windows.

For Linux:

aws ssm get-parameters-by-path \
    --path /aws/service/ami-amazon-linux-latest \
    --query "Parameters[].Name"

For Windows:

aws ssm get-parameters-by-path \
    --path /aws/service/ami-windows-latest \
    --query "Parameters[].Name"

To launch an instance using a public parameter

The following example specifies a Systems Manager public parameter for the image ID to launch an instance using the latest Amazon Linux 2023 AMI.

To specify the parameter in the command, use the following syntax: resolve:ssm:public-parameter, where resolve:ssm is the standard prefix and public-parameter is the path and name of the public parameter.

In this example, the --count and --security-group parameters are not included. For --count, the default is 1. If you have a default VPC and a default security group, they are used.

aws ec2 run-instances \
    --image-id resolve:ssm:/aws/service/ami-amazon-linux-latest/al2023-ami-kernel-default-x86_64 \
    --instance-type m5.xlarge \
    --key-name MyKeyPair

For more information, see Working with public parameters in the AWS Systems Manager User Guide.

For examples that use Systems Manager parameters, see Query for the latest Amazon Linux AMI IDs Using AWS Systems Manager Parameter Store and Query for the Latest Windows AMI Using AWS Systems Manager Parameter Store.