# Configuring Amazon EC2 instances with namespace options
<a name="using-features.managing.ec2.namespace"></a>

You can use the [configuration options](command-options.md) in the `aws:autoscaling:launchconfiguration` namespace to configure the instances for your environment, including additional options that aren't available in the console.

**Important**  
The `DisableIMDSv1`, `RootVolumeType`, or `BlockDeviceMappings` option setting can cause Elastic Beanstalk to migrate an existing environment with launch configurations to launch templates. Doing so requires the necessary permissions to manage launch templates. These permissions are included in our managed policy. If you use custom policies instead of our managed policies, environment creation or updates might fail when you update your environment configuration. For more information and other considerations, see [Migrating your Elastic Beanstalk environment to launch templates](environments-cfg-autoscaling-launch-templates.md).

The following [configuration file](ebextensions.md) example uses the basic configuration options that are explained in this topic. To see examples of additional configuration options when you need to specify security groups for load balancers, see [Configuring with the AWS CLI](using-features.managing.ec2.aws-cli.md).

```
option_settings:
  aws:autoscaling:launchconfiguration:
    SecurityGroups: my-securitygroup
    MonitoringInterval: "1 minute"
    DisableIMDSv1: false
    DisableDefaultEC2SecurityGroup: true
    SecurityGroups: "sg-abcdef01, sg-abcdef02"
    EC2KeyName: my-keypair
    IamInstanceProfile: "aws-elasticbeanstalk-ec2-role"
    BlockDeviceMappings: "/dev/sdj=:100,/dev/sdh=snap-51eef269,/dev/sdb=ephemeral0"   
  aws:elasticbeanstalk:environment:
    EnvironmentType: SingleInstance
```

The `DisableDefaultEC2SecurityGroup` and `BlockDeviceMappings` are not available in the console.

You can use `BlockDeviceMappings` to configure additional block devices for your instances. For more information, see [Block Device Mapping](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/block-device-mapping-concepts.html) in the *Amazon EC2 User Guide*. 

The EB CLI and Elastic Beanstalk console apply recommended values for the preceding options. You must remove these settings if you want to use configuration files to configure the same. See [Recommended values](command-options.md#configuration-options-recommendedvalues) for details.