Configure an Auto Scaling group to use weights - Amazon EC2 Auto Scaling
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Configure an Auto Scaling group to use weights

You can configure an Auto Scaling group to use weights, as shown in the following Amazon CLI examples. For instructions on using the console, see Create a mixed instances group by manually choosing instance types.

To configure a new Auto Scaling group to use weights (Amazon CLI)

Use the create-auto-scaling-group command. For example, the following command creates a new Auto Scaling group and assigns weights by specifying the following:

  • The percentage of the group to launch as On-Demand Instances (0)

  • The allocation strategy for Spot Instances in each Availability Zone (capacity-optimized)

  • The instance types to launch in priority order (m4.16xlarge, m5.24xlarge)

  • The instance weights that correspond to the relative size difference (vCPUs) between instance types (16, 24)

  • The subnets in which to launch the instances (subnet-5ea0c127, subnet-6194ea3b, subnet-c934b782), each corresponding to a different Availability Zone

  • The launch template (my-launch-template) and the launch template version ($Latest)

aws autoscaling create-auto-scaling-group --cli-input-json file://~/config.json

The config.json file contains the following content.

{
    "AutoScalingGroupName": "my-asg",
    "MixedInstancesPolicy": {
        "LaunchTemplate": {
            "LaunchTemplateSpecification": {
                "LaunchTemplateName": "my-launch-template",
                "Version": "$Latest"
            },
            "Overrides": [
                {
                    "InstanceType": "m4.16xlarge",
                    "WeightedCapacity": "16"
                },
                {
                    "InstanceType": "m5.24xlarge",
                    "WeightedCapacity": "24"
                }
            ]
        },
        "InstancesDistribution": {
            "OnDemandPercentageAboveBaseCapacity": 0,
            "SpotAllocationStrategy": "capacity-optimized"
        }
    },
    "MinSize": 160,
    "MaxSize": 720,
    "DesiredCapacity": 480,
    "VPCZoneIdentifier": "subnet-5ea0c127,subnet-6194ea3b,subnet-c934b782",
    "Tags": []
}
To configure an existing Auto Scaling group to use weights (Amazon CLI)

Use the update-auto-scaling-group command. For example, the following command assigns weights to instance types in an existing Auto Scaling group by specifying the following:

  • The instance types to launch in priority order (c5.18xlarge, c5.24xlarge, c5.2xlarge, c5.4xlarge)

  • The instance weights that correspond to the relative size difference (vCPUs) between instance types (18, 24, 2, 4)

  • The new, increased desired capacity, which is larger than the largest weight

aws autoscaling update-auto-scaling-group --cli-input-json file://~/config.json

The config.json file contains the following content.

{
    "AutoScalingGroupName": "my-existing-asg",
    "MixedInstancesPolicy": {
        "LaunchTemplate": {
            "Overrides": [
                {
                    "InstanceType": "c5.18xlarge",
                    "WeightedCapacity": "18"
                },
                {
                    "InstanceType": "c5.24xlarge",
                    "WeightedCapacity": "24"
                },
                {
                    "InstanceType": "c5.2xlarge",
                    "WeightedCapacity": "2"
                },
                {
                    "InstanceType": "c5.4xlarge",
                    "WeightedCapacity": "4"
                }
            ]
        }
    },
    "MinSize": 0,
    "MaxSize": 100,
    "DesiredCapacity": 100
}
To verify the weights using the command line

Use one of the following commands: