# Create a Capacity Reservation Resource Group for UltraServer Capacity Blocks
<a name="cb-group"></a>

You can use AWS Resource Groups to create logical collections of UltraServer Capacity Blocks. After you create the Capacity Reservation Resource Group, you can add UltraServer Capacity Blocks that you own in your account. After you add the UltraServer Capacity Blocks, you can target instances launches to the Capacity Reservation Resource Group instead of the individual Capacity Blocks. Instances that target a Capacity Reservation Resource Group match with any UltraServer Capacity Blocks in the group that has matching attributes and available capacity. If the Capacity Reservation Resource Group does not have an UltraServer Capacity Block with matching attributes and available capacity, the instance launch fails.

If an UltraServer Capacity Block is removed from a Capacity Reservation Resource Group while it has running instances, those instances continue to run in the Capacity Block. If an UltraServer Capacity Block in a group ends while it has running instances, the instances are terminated.

To add instance Capacity Blocks to a Capacity Reservation Resource Group, see [Capacity Reservation Resource Groups](cr-groups.md).

To create a Capacity Reservation Resource Group for UltraServer Capacity Blocks, use one of the following methods.

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#### [ AWS CLI ]

**To create a Capacity Reservation Resource Group for UltraServer Capacity Blocks**  
Use the [create-group](https://docs.aws.amazon.com/cli/latest/reference/resource-groups/create-group.html) AWS CLI command, and for `--configuration`, specify the following:

```
{
  "Configuration": [
    {
      "Type": "AWS::EC2::CapacityReservationPool",
      "Parameters": [
        {
          "Name": "instance-type",
          "Values": [
            "{{instance_type}}"
          ]
        },
        {
          "Name": "reservation-type",
          "Values": [
            "capacity-block"
          ]
        }
      ]
    },
    {
      "Type": "AWS::ResourceGroups::Generic",
      "Parameters": [
        {
          "Name": "allowed-resource-types",
          "Values": [
            "AWS::EC2::CapacityReservation"
          ]
        }
      ]
    }
  ]
}
```

------
#### [ PowerShell ]

**To create a Capacity Reservation Resource Group for UltraServer Capacity Blocks**  
Use the [New-RGGroup](https://docs.aws.amazon.com/powershell/latest/reference/items/New-RGGroup.html) cmdlet. For `-Configuration`, specify the following:

```
{
  "Configuration": [
    {
      "Type": "AWS::EC2::CapacityReservationPool",
      "Parameters": [
        {
          "Name": "instance-type",
          "Values": [
            "{{instance_type}}"
          ]
        },
        {
          "Name": "reservation-type",
          "Values": [
            "capacity-block"
          ]
        }
      ]
    },
    {
      "Type": "AWS::ResourceGroups::Generic",
      "Parameters": [
        {
          "Name": "allowed-resource-types",
          "Values": [
            "AWS::EC2::CapacityReservation"
          ]
        }
      ]
    }
  ]
}
```

------

**Note**  
To add various Capacity Reservation types to an existing UltraServer-only group, you must first modify your group configuration using the [put-group-configuration](https://docs.aws.amazon.com/cli/latest/reference/resource-groups/put-group-configuration.html) API and remove the `instance-type` and `reservation-type` configuration sections. Once complete, see [Capacity Reservation Resource Groups](cr-groups.md) for more grouping operations.

After you create a Capacity Reservation Resource Group for UltraServer Capacity Block, use one of the following methods to add existing UltraServer Capacity Blocks to it.

------
#### [ AWS CLI ]

**To add an UltraServer Capacity Block to a Capacity Reservation Resource Group**  
Use the [ group-resources](https://docs.aws.amazon.com/cli/latest/reference/resource-groups/group-resources.html) command. For `--group` specify the name of the Capacity Reservation Resource Group you created. For `--resource-arns`, specify the ARNs of the UltraServer Capacity Blocks to add.

```
aws resource-groups group-resources \
--group {{MyCRGroup}} \
--resource-arns {{CapacityReservationArn}}
```

------
#### [ PowerShell ]

**To add an UltraServer Capacity Block to a Capacity Reservation Resource Group**  
Use the [Add-RGResource](https://docs.aws.amazon.com/powershell/latest/reference/items/Add-RGResource.html) cmdlet. For `-Group` specify the name of the Capacity Reservation Resource Group you created. For `-ResourceArn `, specify the ARNs of the UltraServer Capacity Blocks to add.

The following example adds two Capacity Reservations to the specified group.

```
Add-RGResource `
-Group {{MyCRGroup}} `
-ResourceArn {{CapacityReservationArn}}
```

------