How to migrate from ECS AL2 to ECS AL2023

Upgrade using Ec2Configuration.ImageType

• If you are not using a launch template or launch template overrides then change Ec2Configuration.ImageType to ECS_AL2023 (or ECS_AL2023_NVIDIA when using GPU instances) and then run UpdateComputeEnvironment.

• If you specify an Ec2Configuration.ImageIdOverride then Ec2Configuration.ImageType must match the AMI type specified in Ec2Configuration.ImageIdOverride.

  If you mismatch ImageIdOverride and ImageType then the compute environment may not function properly.

Upgrade using launch templates

• If you use a launch template that specifies an AMI based on ECS_AL2023, ensure your launch template is compatible with Amazon Linux 2023. For information about changes in Amazon Linux 2023 for Amazon ECS-optimized AMI, see Migrating from an Amazon Linux 2 to an Amazon Linux 2023 Amazon ECS-optimized AMI in the Amazon ECS User Guide.

• For AL2023 AMIs, verify that any custom user data or initialization scripts are compatible with the AL2023 environment and package management system.

Upgrade using AWS CloudFormation

• If you use AWS CloudFormation to manage your compute environments, update your template to change the ImageType property in the Ec2Configuration from ECS_AL2 to ECS_AL2023 (or ECS_AL2023_NVIDIA when using GPU instances):

  ComputeEnvironment:
    Type: AWS::Batch::ComputeEnvironment
    Properties:
      ComputeResources:
        Ec2Configuration:
          - ImageType: ECS_AL2023

  Then update your AWS CloudFormation stack to apply the changes.

• If your AWS CloudFormation template specifies a custom AMI using ImageIdOverride, ensure the AMI ID corresponds to an AL2023-based AMI and matches the ImageType setting.

• Package management – Amazon Linux 2023 uses dnf instead of yum for package management.

• System services – Some system services and their configurations may differ between AL2 and AL2023.

• Container runtime – Both AL2 and AL2023 support Docker, but AL2023 may have different default configurations.

• Security – AL2023 includes enhanced security features and may require updates to security-related configurations.

• Instance Metadata Service Version 2 (IMDSv2) – IMDSv2 is a session-oriented service that requires token-based authentication to access EC2 instance metadata, providing enhanced security. For more information about IMDS see and How Instance Metadata Service Version 2 works in the Amazon EC2 User Guide.