# Allocate an Amazon EC2 Dedicated Host for use in your account
<a name="dedicated-hosts-allocating"></a>

To begin using a Dedicated Host, you must first allocate it in your account. After you allocate the Dedicated Host, the Dedicated Host capacity is made available in your account immediately and you can start launching instances onto the Dedicated Host.

When you allocate a Dedicated Host in your account, you can choose a configuration that supports either a **single instance type**, or ** multiple instance types** within the same instance family. The number of instances that you can run on the host depends on the configuration you choose. For more information see [Amazon EC2 Dedicated Host instance capacity configurations](dedicated-hosts-limits.md).

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

**To allocate a Dedicated Host**

1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).

1. In the navigation pane, choose **Dedicated Hosts** and then choose **Allocate Dedicated Host**.

1. For **Instance family**, choose the instance family for the Dedicated Host.

1. Specify whether the Dedicated Host supports multiple instance sizes within the selected instance family, or a specific instance type only. Do one of the following.
   + To configure the Dedicated Host to support multiple instance types in the selected instance family, for **Support multiple instance types**, choose **Enable**. Enabling this allows you to launch different instance sizes from the same instance family onto the Dedicated Host. For example, if you choose the `m5` instance family and choose this option, you can launch `m5.xlarge` and `m5.4xlarge` instances onto the Dedicated Host.
   + To configure the Dedicated Host to support a single instance type within the selected instance family, clear **Support multiple instance types**, and then for **Instance type**, choose the instance type to support. This allows you to launch a single instance type on the Dedicated Host. For example, if you choose this option and specify `m5.4xlarge` as the supported instance type, you can launch only `m5.4xlarge` instances onto the Dedicated Host.

1. For **Availability Zone**, choose the Availability Zone in which to allocate the Dedicated Host.

1. To allow the Dedicated Host to accept untargeted instance launches that match its instance type, for **Instance auto-placement**, choose **Enable**. For more information about auto-placement, see [Amazon EC2 Dedicated Host auto-placement and host affinity](dedicated-hosts-understanding.md).

1. To enable host recovery for the Dedicated Host, for **Host recovery**, choose **Enable**. For more information, see [Amazon EC2 Dedicated Host recovery](dedicated-hosts-recovery.md).

1. For **Quantity**, enter the number of Dedicated Hosts to allocate.

1. (Optional) Choose **Add new tag** and enter a tag key and a tag value.

1. Choose **Allocate**.

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

**To allocate a Dedicated Host**  
Use the [allocate-hosts](https://docs.aws.amazon.com/cli/latest/reference/ec2/allocate-hosts.html) command. The following example allocates a Dedicated Host that supports multiple instance types from the `m5` instance family in the `us-east-1a` Availability Zone. It also enables host recovery and disables auto-placement.

```
aws ec2 allocate-hosts \
    --instance-family "m5" \
    --availability-zone "us-east-1a" \
    --auto-placement "off" \
    --host-recovery "on" \ 
    --quantity 1
```

The following example allocates a Dedicated Host that supports *untargeted* instance launches in the specified Availability Zone, enables host recovery, and enables auto-placement.

```
aws ec2 allocate-hosts \
    --instance-type "m5.large" \
    --availability-zone "eu-west-1a" \
    --auto-placement "on" \
    --host-recovery "on" \
    --quantity 1
```

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

**To allocate a Dedicated Host**  
Use the [New-EC2Host](https://docs.aws.amazon.com/powershell/latest/reference/items/New-EC2Host.html) cmdlet. The following example allocates a Dedicated Host that supports multiple instance types from the `m5` instance family in the `us-east-1a` Availability Zone. The host also has host recovery enabled and auto-placement disabled.

```
New-EC2Host `
    -InstanceFamily m5 `
    -AvailabilityZone us-east-1a `
    -AutoPlacement Off `
    -HostRecovery On `
    -Quantity 1
```

The following example allocates a Dedicated Host that supports *untargeted* instance launches in the specified Availability Zone and enables host recovery.

```
New-EC2Host `
    -InstanceType m5.large `
    -AvailabilityZone eu-west-1a `
    -AutoPlacement On `
    -HostRecovery On `
    -Quantity 1
```

------