Create a container group definition for an Amazon GameLift container fleet

A container group definition describes how to deploy your containerized game server applications to a container fleet. It's a blueprint that tells Amazon GameLift what container images to deploy to the fleet and how to run them. When you create a container fleet, you specify the container group definitions to deploy to the fleet. For more information about container groups, see Container fleet components.

Before you start

Tips on what to do before you start creating a container group definition:

• Finalize your container images and push them to an Amazon Elastic Container Registry (Amazon ECR) repository in the same AWS Region where you plan to create the container group. Amazon GameLift captures a snapshot of each image at the time you create container group definition, and uses the snapshot when deploying to a container fleet. See Build a container image for Amazon GameLift.

• Create your container definitions as JSON files. A container group definition includes one or more container definitions. You can use the JSON files if you create a container group definition using the AWS CLIfor Amazon GameLift.

• Verify that your AWS user has IAM permissions to access the Amazon ECR repository. See IAM permission examples for Amazon GameLift.

Create a game server container group definition

A game server container group runs your game server software. A game server container group has one game server container, which runs the game server executable. It can also have one or more support containers to run additional software to support your game server. (These are sometimes referred to as “sidecar” containers.)

This topic describes how to create a simple game server container group definition using the Amazon GameLift console or AWS CLI tools. For more detailed information on optional features, see Customize an Amazon GameLift container fleet.

Note

You can change most container group definition and container definition settings after creating them. If you make changes to a container definition, Amazon GameLift captures a new snapshot of the updated container images.

To create a simple game server container group definition:

The following instructions describe how to create a container group definition with the minimal required parameters and using the Amazon GameLift default values.

Console

In the Amazon GameLift console, select the AWS Region where you want to create the container group.

Open the console’s left navigation bar and choose Managed containers: Group definitions. On the Container groups definition page, choose Create group definition.

Step 1: Define container group definition details

1. Enter a container group definition name. The name must be unique to the AWS account and Region.

2. Select the Game server container group type.

3. For Total memory limit, enter the maximum memory resources to make available for all containers in the container group. For help calculating this value, see Set resource limits.

4. For Total vCPU limit, enter the maximum computing power to make available for all containers in the container group. For help calculating this value, see Set resource limits.

Step 2: Add container definitions

At minimum, a game server container group has one game server container. In the console, the first container definition you create is the game server container. This step describes how to define the minimum required settings for a game server container definition.

1. Enter a container definition Name. Each container defined for the group must have a unique name value.

2. Link to a container image with your game server build. Enter the Amazon ECR image URI for a container image in a public or private repository. You can use any of the following formats:

   • Image URI only: [AWS account].dkr.ecr.[AWS Region].amazonaws.com/[repository ID]

   • Image URI + digest: [AWS account].dkr.ecr.[AWS Region].amazonaws.com/[repository ID]@[digest]

   • Image URI + tag: [AWS account].dkr.ecr.[AWS Region].amazonaws.com/[repository ID]:[tag]

3. Specify the Amazon GameLift Server SDK version that the game server build uses. For a container fleet, this value must be 5.2.0 or greater.

4. In Internal container port range, set the protocol and define a port range. The range size must be greater than the number of concurrent game server processes that will run in this container. If the game server container runs only one server process per container, this port range only needs a few ports. For more details, see Configure network connections.

5. Add more containers as needed to run additional support software. Additional containers are automatically designated support containers. A game server container group can have only one game server containers and up to eight support containers. Provide the following minimal required settings:

   • Container definition Name

   • ECR image URI.

   • Internal container ports (Include this only if the container has processes that need network access.)

Step 3: Configure dependencies

• If your container group definition has more than one container, you can optionally set dependencies between the containers. For more information, see Set container dependencies.

Step 3: Review and create

1. Review all your container group definition settings. Use Edit to make changes to any section, including each of your container definitions for the group.

2. When you're finished reviewing, choose Create.

   If your request is successful, the console displays the detail page for the new container group definition resource. Initially the status is COPYING, as Amazon GameLift starts taking snapshots of all the container images for the group. When this phase is complete, the container group definition status changes to READY. A container group definition must be in READY status before you can create a container fleet with it.

AWS CLI

When you use the AWS CLI to create a container group definition, maintain your container definition configurations in a separate JSON file. You can reference the file in your CLI command. See Create a container definition JSON file for schema examples.

Create a container group definition

To create a new container group definition, use the create-container-group-definition CLI command. For more information about this command, see create-container-group-definition in the AWS CLI Command Reference.

This example illustrates a request for a game server container group definition. It assumes that you’ve created a JSON file with the container definitions for this group.

aws gamelift create-container-group-definition \
    --name MyAdventureGameContainerGroup \
    --operating-system AMAZON_LINUX_2023 \
    --container-group-type GAME_SERVER \
    --total-memory-limit-mebibytes 4096 \
    --total-vcpu-limit 1 \
    --container-definitions file://MyAdventureGameContainers.json

Create a container definition JSON file

When you create a container group definition, you also define the containers for the group. A container definition specifies the Amazon ECR repository where the container image is stored, and optional configurations for network ports, limits for CPU and memory usage, and other settings. We recommend creating a single JSON file with the configurations for all the containers in a container group. Maintaining a file is useful for storing, sharing, version tracking these critical configurations. If you use the AWS CLI to create your container group definitions, you can reference the file in the command.

To create a container definition

1. Create and open a new .JSON file. For example:

   [~/work/glc]$ vim SimpleServer.json

2. Create a separate container definition for each of the containers for the group. Copy the following example content and modify it as needed for your containers. For details on the syntax of a container definition, see ContainerDefinitionInput in the Amazon GameLift API Reference.

3. Save the file locally so that you can refer to it in an AWS CLI command.

Example: Game server container definition

This example describes the essential container for your game server container group. The essential replica container includes your game server application, the Amazon GameLift Agent, and can include other supporting software for your game hosting. The definition must include a name, image URI, and a port configuration. This example also sets some container-specific resource limits.

[
  {
    "ContainerName": "MyAdventureGameServer",
    "ImageUri": "111122223333.dkr.ecr.us-east-1.amazonaws.com/gl-containers:myadventuregame-server",
    "PortConfiguration": {
      "ContainerPortRanges": [
        {
          "FromPort": 2000,
          "Protocol": "TCP",
          "ToPort": 2010
        }
      ]
    },
    "ServerSdkVersion": 5.2.0
  }
]