# Configure automatic scaling on an existing table
<a name="autoscaling.configureTable"></a>

You can update an existing Amazon Keyspaces table to turn on auto scaling for the table's write or read capacity. If you're updating a table that is currently in on-demand capacity mode, than you first have to change the table's capacity mode to provisioned capacity mode.

For more information on how to update auto scaling settings for a multi-Region table, see [Update the provisioned capacity and auto scaling settings for a multi-Region table in Amazon Keyspaces](tables-mrr-autoscaling.md).

Amazon Keyspaces automatic scaling requires the presence of a service-linked role (`AWSServiceRoleForApplicationAutoScaling_CassandraTable`) that performs automatic scaling actions on your behalf. This role is created automatically for you. For more information, see [Using service-linked roles for Amazon Keyspaces](using-service-linked-roles.md).

------
#### [ Console ]

**Configure Amazon Keyspaces automatic scaling for an existing table**

1. Sign in to the AWS Management Console, and open the Amazon Keyspaces console at [https://console.aws.amazon.com/keyspaces/home](https://console.aws.amazon.com/keyspaces/home).

1. Choose the table that you want to work with, and go to the **Capacity** tab.

1. In the **Capacity settings** section, choose **Edit**.

1. Under **Capacity mode**, make sure that the table is using **Provisioned** capacity mode.

1. Select **Scale automatically** and see step 6 in [Create a new table with automatic scaling](autoscaling.createTable.md) to edit read and write capacity.

1. When the automatic scaling settings are defined, choose **Save**.

------
#### [ Cassandra Query Language (CQL) ]

**Configure an existing table with Amazon Keyspaces automatic scaling using CQL**

You can use the `ALTER TABLE` statement for an existing Amazon Keyspaces table to configure auto scaling for the table's write or read capacity. If you're updating a table that is currently in on-demand capacity mode, you have to set `capacity_mode` to provisioned. If your table is already in provisioned capacity mode, this field can be omitted. 

In the following example, the statement updates the table *mytable*, which is in on-demand capacity mode. The statement changes the capacity mode of the table to provisioned mode with auto scaling enabled. 

The write capacity is configured within the range of 5–10 capacity units with a target value of 50%. The read capacity is also configured within the range of 5–10 capacity units with a target value of 50%. For read capacity, you set the values for `scale_out_cooldown` and `scale_in_cooldown` to 60 seconds.

```
ALTER TABLE mykeyspace.mytable
WITH CUSTOM_PROPERTIES = {  
    'capacity_mode': {  
        'throughput_mode': 'PROVISIONED',  
        'read_capacity_units': 1,  
        'write_capacity_units': 1  
    }
} AND AUTOSCALING_SETTINGS = {
    'provisioned_write_capacity_autoscaling_update': {
        'maximum_units': 10,  
        'minimum_units': 5,  
        'scaling_policy': {
            'target_tracking_scaling_policy_configuration': {
                'target_value': 50
            }  
        }  
    },
    'provisioned_read_capacity_autoscaling_update': {  
        'maximum_units': 10,  
        'minimum_units': 5,  
        'scaling_policy': {  
            'target_tracking_scaling_policy_configuration': {  
                'target_value': 50,
                'scale_in_cooldown': 60,  
                'scale_out_cooldown': 60
            }  
        }  
    }
};
```

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

**Configure an existing table with Amazon Keyspaces automatic scaling using the AWS CLI**

For an existing Amazon Keyspaces table, you can turn on auto scaling for the table's write or read capacity using the `UpdateTable` operation. 

You can use the following command to turn on Amazon Keyspaces auto scaling for an existing table. The auto scaling settings for the table are loaded from a JSON file. For the following example, you can download the example JSON file from [auto-scaling.zip](samples/auto-scaling.zip) and extract `auto-scaling.json`, taking note of the path to the file. In this example, the JSON file is located in the current directory. For different file path options, see [ How to load parameters from a file](https://docs.aws.amazon.com/cli/latest/userguide/cli-usage-parameters-file.html#cli-usage-parameters-file-how).

For more information about the auto scaling settings used in the following example, see [Create a new table with automatic scaling](autoscaling.createTable.md).

```
aws keyspaces update-table --keyspace-name mykeyspace --table-name mytable 
            \ --capacity-specification throughputMode=PROVISIONED,readCapacityUnits=1,writeCapacityUnits=1 
            \ --auto-scaling-specification file://auto-scaling.json
```

------