Create a launch configuration - Amazon EC2 Auto Scaling
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Create a launch configuration

Important

You can not call CreateLaunchConfiguration with new Amazon EC2 instance types that are released after December 31, 2022. In addition, any new accounts created on or after June 1, 2023 will not have the option to create new launch configurations through the console. However, API, CLI, and CloudFormation access will be available to new accounts created between June 1, 2023 and December 31, 2023 to support customers with automation use cases. New accounts created on or after January 1, 2024 will not be able to create new launch configurations by using the console, API, CLI, and CloudFormation. For information about migrating your Auto Scaling groups to launch templates, see Migrate to launch templates.

This topic describes how to create a launch configuration.

After you create a launch configuration, you cannot modify it. Instead, you must create a new launch configuration.

To associate a new launch configuration with an existing Auto Scaling group, see Change the launch configuration for an Auto Scaling group. To create a new Auto Scaling group, see Create an Auto Scaling group using a launch configuration.

Create a launch configuration

To create a launch configuration (console)
  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. On the top navigation bar, select your Amazon Region.

  3. On the left navigation pane, under Auto Scaling, choose Auto Scaling Groups.

  4. Choose Launch configurations near the top of the page. When prompted for confirmation, choose View launch configurations to confirm that you want to view the Launch configurations page.

  5. Choose Create launch configuration, and enter a name for your launch configuration.

  6. For Amazon machine image (AMI) , choose an AMI. To find a specific AMI, you can find a suitable AMI, make note of its ID, and enter the ID as search criteria.

    To get the ID of the Amazon Linux 2 AMI:

    1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

    2. On the left navigation pane, under Instances, choose Instances, and then choose Launch instances.

    3. On the Quick Start tab of the Choose an Amazon Machine Image page, note the ID of the AMI next to Amazon Linux 2 AMI (HVM).

  7. For Instance type, select a hardware configuration for your instances.

  8. Under Additional configuration, pay attention to the following fields:

    1. (Optional) For Purchasing option, you can choose Request Spot Instances to request Spot Instances at the Spot price, capped at the On-Demand price. Optionally, you can specify a maximum price per instance hour for your Spot Instances.

      Note

      Spot Instances are a cost-effective choice compared to On-Demand Instances, if you can be flexible about when your applications run and if your applications can be interrupted. For more information, see Request Spot Instances for fault-tolerant and flexible applications.

    2. (Optional) For IAM instance profile, choose a role to associate with the instances. For more information, see IAM role for applications that run on Amazon EC2 instances.

    3. (Optional) For Monitoring, choose whether to enable the instances to publish metric data at 1-minute intervals to Amazon CloudWatch by enabling detailed monitoring. Additional charges apply. For more information, see Configure monitoring for Auto Scaling instances.

    4. (Optional) For Advanced details, User data, you can specify user data to configure an instance during launch, or to run a configuration script after the instance starts.

    5. (Optional) For Advanced details, IP address type, choose whether to assign a public IP address to the group's instances. If you do not set a value, the default is to use the auto-assign public IP settings of the subnets that your instances are launched into.

  9. (Optional) For Storage (volumes), if you don't need additional storage, you can skip this section. Otherwise, to specify volumes to attach to the instances in addition to the volumes specified by the AMI, choose Add new volume. Then choose the desired options and associated values for Devices, Snapshot, Size, Volume type, IOPS, Throughput, Delete on termination, and Encrypted.

  10. For Security groups, create or select the security group to associate with the group's instances. If you leave the Create a new security group option selected, a default SSH rule is configured for Amazon EC2 instances running Linux. A default RDP rule is configured for Amazon EC2 instances running Windows.

  11. For Key pair (login), choose an option under Key pair options.

    If you've already configured an Amazon EC2 instance key pair, you can choose it here.

    If you don't already have an Amazon EC2 instance key pair, choose Create a new key pair and give it a recognizable name. Choose Download key pair to download the key pair to your computer.

    Important

    If you need to connect to your instances, do not choose Proceed without a key pair.

  12. Select the acknowledgment check box, and then choose Create launch configuration.

To create a launch configuration from an existing launch configuration (console)
  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. On the top navigation bar, select your Amazon Region.

  3. On the left navigation pane, under Auto Scaling, choose Auto Scaling Groups.

  4. Choose Launch configurations near the top of the page. When prompted for confirmation, choose View launch configurations to confirm that you want to view the Launch configurations page.

  5. Select the launch configuration and choose Actions, Copy launch configuration. This sets up a new launch configuration with the same options as the original, but with "Copy" added to the name.

  6. On the Copy Launch Configuration page, edit the configuration options as needed and choose Create launch configuration.

To create a launch configuration using the command line

You can use one of the following commands:

Configure the instance metadata options

Amazon EC2 Auto Scaling supports configuring the Instance Metadata Service (IMDS) in launch configurations. This gives you the option of using launch configurations to configure the Amazon EC2 instances in your Auto Scaling groups to require Instance Metadata Service Version 2 (IMDSv2), which is a session-oriented method for requesting instance metadata. For details about IMDSv2's advantages, see this article on the Amazon Blog about enhancements to add defense in depth to the EC2 instance metadata service.

You can configure IMDS to support both IMDSv2 and IMDSv1 (the default), or to require the use of IMDSv2. If you are using the Amazon CLI or one of the SDKs to configure IMDS, you must use the latest version of the Amazon CLI or the SDK to require the use of IMDSv2.

You can configure your launch configuration for the following:

  • Require the use of IMDSv2 when requesting instance metadata

  • Specify the PUT response hop limit

  • Turn off access to instance metadata

You can find more details on configuring the Instance Metadata Service in the following topic: Configuring the instance metadata service in the Amazon EC2 User Guide for Linux Instances.

Use the following procedure to configure IMDS options in a launch configuration. After you create your launch configuration, you can associate it with your Auto Scaling group. If you associate the launch configuration with an existing Auto Scaling group, the existing launch configuration is disassociated from the Auto Scaling group, and existing instances will require replacement to use the IMDS options that you specified in the new launch configuration. For more information, see Change the launch configuration for an Auto Scaling group.

To configure IMDS in a launch configuration (console)
  1. Open the Amazon EC2 console at https://console.amazonaws.cn/ec2/.

  2. On the top navigation bar, select your Amazon Region.

  3. On the left navigation pane, under Auto Scaling, choose Auto Scaling Groups.

  4. Choose Launch configurations near the top of the page. When prompted for confirmation, choose View launch configurations to confirm that you want to view the Launch configurations page.

  5. Choose Create launch configuration, and create the launch configuration the usual way. Include the ID of the Amazon Machine Image (AMI), the instance type, and optionally, a key pair, one or more security groups, and any additional EBS volumes or instance store volumes for your instances.

  6. To configure instance metadata options for all of the instances associated with this launch configuration, in Additional configuration, under Advanced details, do the following:

    1. For Metadata accessible, choose whether to enable or disable access to the HTTP endpoint of the instance metadata service. By default, the HTTP endpoint is enabled. If you choose to disable the endpoint, access to your instance metadata is turned off. You can specify the condition to require IMDSv2 only when the HTTP endpoint is enabled.

    2. For Metadata version, you can choose to require the use of Instance Metadata Service Version 2 (IMDSv2) when requesting instance metadata. If you do not specify a value, the default is to support both IMDSv1 and IMDSv2.

    3. For Metadata token response hop limit, you can set the allowable number of network hops for the metadata token. If you do not specify a value, the default is 1.

  7. When you have finished, choose Create launch configuration.

To require the use of IMDSv2 in a launch configuration using the Amazon CLI

Use the following create-launch-configuration command with --metadata-options set to HttpTokens=required. When you specify a value for HttpTokens, you must also set HttpEndpoint to enabled. Because the secure token header is set to required for metadata retrieval requests, this opts in the instance to require using IMDSv2 when requesting instance metadata.

aws autoscaling create-launch-configuration \ --launch-configuration-name my-lc-with-imdsv2 \ --image-id ami-01e24be29428c15b2 \ --instance-type t2.micro \ ... --metadata-options "HttpEndpoint=enabled,HttpTokens=required"
To turn off access to instance metadata

Use the following create-launch-configuration command to turn off access to instance metadata. You can turn access back on later by using the modify-instance-metadata-options command.

aws autoscaling create-launch-configuration \ --launch-configuration-name my-lc-with-imds-disabled \ --image-id ami-01e24be29428c15b2 \ --instance-type t2.micro \ ... --metadata-options "HttpEndpoint=disabled"

Create a launch configuration using an EC2 instance

You also have the option to create a launch configuration using the attributes from a running EC2 instance.

There are differences between creating a launch configuration from scratch and creating a launch configuration from an existing EC2 instance. When you create a launch configuration from scratch, you specify the image ID, instance type, optional resources (such as storage devices), and optional settings (like monitoring). When you create a launch configuration from a running instance, Amazon EC2 Auto Scaling derives attributes for the launch configuration from the specified instance. Attributes are also derived from the block device mapping for the AMI from which the instance was launched, ignoring any additional block devices that were added after launch.

When you create a launch configuration using a running instance, you can override the following attributes by specifying them as part of the same request: AMI, block devices, key pair, instance profile, instance type, kernel, instance monitoring, placement tenancy, ramdisk, security groups, Spot (max) price, user data, whether the instance has a public IP address, and whether the instance is EBS-optimized.

Note

If the specified instance has properties that are not currently supported by launch configurations, the instances launched by the Auto Scaling group might not be identical to the original EC2 instance.

Important

The AMI used to launch the specified instance must still exist.

Create a launch configuration from an EC2 instance (Amazon CLI)

Use the following create-launch-configuration command to create a launch configuration from an instance using the same attributes as the instance. Any block devices added after launch are ignored.

aws autoscaling create-launch-configuration --launch-configuration-name my-lc-from-instance --instance-id i-a8e09d9c

You can use the following describe-launch-configurations command to describe the launch configuration and verify that its attributes match those of the instance.

aws autoscaling describe-launch-configurations --launch-configuration-names my-lc-from-instance

The following is an example response.

{ "LaunchConfigurations": [ { "UserData": null, "EbsOptimized": false, "LaunchConfigurationARN": "arn", "InstanceMonitoring": { "Enabled": false }, "ImageId": "ami-05355a6c", "CreatedTime": "2014-12-29T16:14:50.382Z", "BlockDeviceMappings": [], "KeyName": "my-key-pair", "SecurityGroups": [ "sg-8422d1eb" ], "LaunchConfigurationName": "my-lc-from-instance", "KernelId": "null", "RamdiskId": null, "InstanceType": "t1.micro", "AssociatePublicIpAddress": true } ] }

Create a launch configuration from an instance and override the block devices (Amazon CLI)

By default, Amazon EC2 Auto Scaling uses the attributes from the EC2 instance that you specify to create the launch configuration. However, the block devices come from the AMI used to launch the instance, not the instance. To add block devices to the launch configuration, override the block device mapping for the launch configuration.

Use the following create-launch-configuration command to create a launch configuration using an EC2 instance but with a custom block device mapping.

aws autoscaling create-launch-configuration --launch-configuration-name my-lc-from-instance-bdm --instance-id i-a8e09d9c \ --block-device-mappings "[{\"DeviceName\":\"/dev/sda1\",\"Ebs\":{\"SnapshotId\":\"snap-3decf207\"}},{\"DeviceName\":\"/dev/sdf\",\"Ebs\":{\"SnapshotId\":\"snap-eed6ac86\"}}]"

Use the following describe-launch-configurations command to describe the launch configuration and verify that it uses your custom block device mapping.

aws autoscaling describe-launch-configurations --launch-configuration-names my-lc-from-instance-bdm

The following example response describes the launch configuration.

{ "LaunchConfigurations": [ { "UserData": null, "EbsOptimized": false, "LaunchConfigurationARN": "arn", "InstanceMonitoring": { "Enabled": false }, "ImageId": "ami-c49c0dac", "CreatedTime": "2015-01-07T14:51:26.065Z", "BlockDeviceMappings": [ { "DeviceName": "/dev/sda1", "Ebs": { "SnapshotId": "snap-3decf207" } }, { "DeviceName": "/dev/sdf", "Ebs": { "SnapshotId": "snap-eed6ac86" } } ], "KeyName": "my-key-pair", "SecurityGroups": [ "sg-8637d3e3" ], "LaunchConfigurationName": "my-lc-from-instance-bdm", "KernelId": null, "RamdiskId": null, "InstanceType": "t1.micro", "AssociatePublicIpAddress": true } ] }

Create a launch configuration and override the instance type (Amazon CLI)

By default, Amazon EC2 Auto Scaling uses the attributes from the EC2 instance you specify to create the launch configuration. Depending on your requirements, you might want to override attributes from the instance and use the values that you need. For example, you can override the instance type.

Use the following create-launch-configuration command to create a launch configuration using an EC2 instance but with a different instance type (for example t2.medium) than the instance (for example t2.micro).

aws autoscaling create-launch-configuration --launch-configuration-name my-lc-from-instance-changetype \ --instance-id i-a8e09d9c --instance-type t2.medium

Use the following describe-launch-configurations command to describe the launch configuration and verify that the instance type was overridden.

aws autoscaling describe-launch-configurations --launch-configuration-names my-lc-from-instance-changetype

The following example response describes the launch configuration.

{ "LaunchConfigurations": [ { "UserData": null, "EbsOptimized": false, "LaunchConfigurationARN": "arn", "InstanceMonitoring": { "Enabled": false }, "ImageId": "ami-05355a6c", "CreatedTime": "2014-12-29T16:14:50.382Z", "BlockDeviceMappings": [], "KeyName": "my-key-pair", "SecurityGroups": [ "sg-8422d1eb" ], "LaunchConfigurationName": "my-lc-from-instance-changetype", "KernelId": "null", "RamdiskId": null, "InstanceType": "t2.medium", "AssociatePublicIpAddress": true } ] }