# OperatingSystemType

The OS type of a particular image.

- Source: [`aws-ec2/lib/machine-image/common.ts`](https://github.com/aws/aws-cdk/blob/v2.275.0/packages/aws-cdk-lib/aws-ec2/lib/machine-image/common.ts#L150)

## Example

```ts
// Pick the right Amazon Linux edition. All arguments shown are optional
// and will default to these values when omitted.
const amznLinux = ec2.MachineImage.latestAmazonLinux({
  generation: ec2.AmazonLinuxGeneration.AMAZON_LINUX,
  edition: ec2.AmazonLinuxEdition.STANDARD,
  virtualization: ec2.AmazonLinuxVirt.HVM,
  storage: ec2.AmazonLinuxStorage.GENERAL_PURPOSE,
  cpuType: ec2.AmazonLinuxCpuType.X86_64,
});

// Pick a Windows edition to use
const windows = ec2.MachineImage.latestWindows(ec2.WindowsVersion.WINDOWS_SERVER_2019_ENGLISH_FULL_BASE);

// Read AMI id from SSM parameter store
const ssm = ec2.MachineImage.fromSsmParameter('/my/ami', { os: ec2.OperatingSystemType.LINUX });

// Look up the most recent image matching a set of AMI filters.
// In this case, look up the NAT instance AMI, by using a wildcard
// in the 'name' field:
const natAmi = ec2.MachineImage.lookup({
  name: 'amzn-ami-vpc-nat-*',
  owners: ['amazon'],
});

// For other custom (Linux) images, instantiate a `GenericLinuxImage` with
// a map giving the AMI to in for each region:
const linux = ec2.MachineImage.genericLinux({
  'us-east-1': 'ami-97785bed',
  'eu-west-1': 'ami-12345678',
  // ...
});

// For other custom (Windows) images, instantiate a `GenericWindowsImage` with
// a map giving the AMI to in for each region:
const genericWindows = ec2.MachineImage.genericWindows({
  'us-east-1': 'ami-97785bed',
  'eu-west-1': 'ami-12345678',
  // ...
});
```

## Members

| Member | Description |
| --- | --- |
| `LINUX` |  |
| `WINDOWS` |  |
| `UNKNOWN` | Used when the type of the operating system is not known (for example, for imported Auto-Scaling Groups). |

## Referenced by

- [`AttachInitOptions`](/v2/docs/aws-cdk-lib.aws_ec2.AttachInitOptions).platform
- [`AutoScalingGroup`](/v2/docs/aws-cdk-lib.aws_autoscaling.AutoScalingGroup).osType
- [`IAutoScalingGroup`](/v2/docs/aws-cdk-lib.aws_autoscaling.IAutoScalingGroup).osType
- [`Instance`](/v2/docs/aws-cdk-lib.aws_ec2.Instance).osType
- [`LaunchTemplate`](/v2/docs/aws-cdk-lib.aws_ec2.LaunchTemplate).osType
- [`MachineImageConfig`](/v2/docs/aws-cdk-lib.aws_ec2.MachineImageConfig).osType
- [`SsmParameterImageOptions`](/v2/docs/aws-cdk-lib.aws_ec2.SsmParameterImageOptions).os