# Migrate to Nitro-based Amazon EC2 Dedicated Hosts
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The Nitro System is a collection of hardware and software components built by AWS that enable high performance, high availability, and high security. Nitro-based Dedicated Hosts offer improved price performance compared to Xen-based Dedicated Hosts. If you have any Xen-based Dedicated Hosts in your account, we recommend that you migrate your workloads to Nitro-based Dedicated Hosts. For more information, see [AWS Nitro System](https://aws.amazon.com/ec2/nitro/).

To migrate from a Xen-based Dedicated Host to a Nitro-based Dedicated Host, you need to migrate the Xen-based instances on your Dedicated Host to Nitro-based instance types, allocate a new Nitro-based Dedicated Host, and then move your migrated Nitro-based instances to your new Nitro-based Dedicated Host. 

This topic provides detailed steps for migrating from Xen-based Dedicated Hosts to Nitro-based Dedicated Hosts.

**Topics**
+ [Step 1: Identify your Xen-based Dedicated Hosts](#identify-xen-hosts)
+ [Step 2: Migrate Xen-based instances to Nitro-based instance types](#migrate-dh-instances)
+ [Step 3: Allocate a Nitro-based Dedicated Host](#allocate-nitro-host)
+ [Step 4: Move migrated instances to new Nitro-based Dedicated Host](#move-instances)
+ [Step 5: Release unused Xen-based Dedicated Host](#release-xen-instances)

## Step 1: Identify your Xen-based Dedicated Hosts
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The following Dedicated Hosts are Xen-based and are eligible to be migrated to Nitro-based Dedicated Hosts.
+ **General purpose: **M3 \$1 M4
+ **Compute optimized: **C3 \$1 C4
+ **Memory optimized: **R3 \$1 R4 \$1 X1 \$1 X1e
+ **Storage optimized: **D2 \$1 H1 \$1 I2 \$1 I3
+ **Accelerated computing: **F1 \$1 G3 \$1 P2 \$1 P3

**To check if you have Xen-based Dedicated Hosts in your account**

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

1. In the navigation panel, choose **Dedicated Hosts**.

1. In the **Search field**, use the **Instance family** filter to search for the Xen-based Dedicated Hosts above. For example, *Instance family = m3*.

## Step 2: Migrate Xen-based instances to Nitro-based instance types
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Instances that run on Xen-based Dedicated Hosts are also Xen-based. You must migrate these instances to Nitro-based instance types before you can move them to Nitro-based Dedicated Hosts.

**Important**  
Before you begin migrating your instances, we recommend that you back up your data. For more information, see [Create multi-volume Amazon EBS snapshots from an Amazon EC2 instance](https://docs.aws.amazon.com/ebs/latest/userguide/ebs-create-snapshots.html).

**To find instances running on your Xen-based Dedicated Hosts**

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

1. In the navigation panel, choose **Dedicated Hosts**.

1. Select the Xen-based host you intend to migrate and then select the **Running instances** tab. The tab lists all of the instances running of the selected host.

To migrate **Linux instances**, see [Amazon EC2 instance type changes](ec2-instance-resize.md).

To migrate **Windows instances**, see [Migrate an EC2 Windows instance to a Nitro-based instance type](migrating-latest-types.md).

**Note**  
Ensure that you migrate your instances to an instance type that matches the Nitro-based Dedicated Host that you intend to migrate to. For example, if you intend to migrate to a M7i Dedicated Host, ensure that you migrate your instances to an M7i instance type.

## Step 3: Allocate a Nitro-based Dedicated Host
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**To find supported Nitro-based Dedicated Hosts**

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

1. In the navigation panel, select **Instance Types**.

1. Apply the following filters:
   + *Hypervisor = nitro*
   + *Dedicated Host support = true*

After you've found a suitable Nitro-based instance type, [ allocate a new Dedicated Host](dedicated-hosts-allocating.md).

## Step 4: Move migrated instances to new Nitro-based Dedicated Host
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After you have allocated the Nitro-based Dedicated Host and it reaches the `available` state, you can move the instances that you previously migrated to Nitro-based instance types to the new Dedicated Host.

**To move your instances to your new Nitro-based 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 panel, **Instances**.

1. Select the instance that you migrated and choose **Actions**, **Instance settings**, **Modify instance placement**.

1. For **Target dedicated host**, select the new Nitro-based Dedicated Host, and then choose **Save**.

1. Restart the instance. Select the instance and choose **Instance state**, **Start instance**.

## Step 5: Release unused Xen-based Dedicated Host
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After you have migrated your workloads from the Xen-based Dedicated Host to the new Nitro-based Dedicated Host, you can [release the Xen-based Dedicated Host](dedicated-hosts-releasing.md) if you no longer need it.