Azure VM: Restore a VM (Instant Restore)

Who can use this feature

Anyone with these permissions: Restore resources

Use instant restore when you need the VM back in service before all its disk data is restored. Instant restore makes the VM available while Eon hydrates its disks, which means it copies disk data from your vault to the managed disks in the background. Eon serves data on demand until hydration finishes. While the disks hydrate, Eon runs your VM nested inside a temporary restore server, which is a VM in your resource group.

This article explains how to restore an Azure virtual machine (VM) from your Eon snapshots using instant restore. For the standard restore method that fully restores every disk before the VM becomes available, see Azure VM: Restore a VM.

Restore the VM with instant restore

Before you start

Before you restore an Azure VM with instant restore, make sure:

A restore account has been connected to your Eon account.

Your restore subscription has restore permissions version 1.17.0 or later, or version 1.19.0 or later if your restore account is scoped to a single resource group.
The source VM is an x86_64 generation 2 VM. See Restore support notes for the full list of unsupported configurations.
The subnet you plan to use for the restored VM meets these requirements:
- It isn’t delegated to a service.
- It has at least two free IP addresses.
- It has an outbound path to the internet, such as a NAT gateway.
- It has a Microsoft.Storage service endpoint. If the subnet needs one, the restore wizard shows a message.
Your restore subscription has enough vCPU quota in the vault’s region for the restore server and the VM size you choose.
- Eon sizes the restore server from VM sizes that support nested virtualization, such as the Dsv5 or Esv5 series.
- Promotion resizes the VM to the size you choose.

Find the snapshot you want to restore

In your inventory, select the Azure VM you want to restore. The Resource details panel opens.
Click the Eon snapshots tab. You’ll see a calendar view with colored dots on the days when snapshots were taken. There can be more than one snapshot per day.

When you click a day, a list of Eon snapshots taken that day is displayed below the calendar.
Expand the snapshot you want to restore. Click Instance, and then click Restore. The Restore virtual machine wizard opens.

Choose the restore account

In the Restore virtual machine wizard, you’re taken through a three-step process. The first step is to choose a restore account.

Choose the subscription you want to restore to, and then click Next.

Turn on instant restore and set the instance details

In the Instance configuration step, you’ll set the instance details.

Turn Use instant restore on.

If the switch is unavailable, hover over it to see why. With instant restore, the VM restores to the same region as your vault, and Region selection isn’t available. The VM starts automatically, so Start instance after restore isn’t displayed.
Enter a VM name for the restored VM.
Choose a Resource group to deploy the restored VM to.
In Network Interface configuration, choose an existing virtual network and subnet for the restored VM. Eon creates a new network interface in this subnet, which becomes the restored VM’s network interface. Eon also creates a temporary management network interface in this subnet, which is why the subnet needs two free IP addresses.
Choose the Virtual machine size. You can keep the original VM size, or select a different size. ARM64 sizes aren’t available with instant restore. For information on available options, see Azure VM sizes from Microsoft.
If you want to retain the tags that were present when the snapshot was taken, turn Keep original tags on. Otherwise, turn Keep original tags off.
Click Next.

Set details for the attached disks

In this step of the wizard, you’ll set the disk settings and tags for the disks attached to the VM. Expand individual disks to show disk-specific settings.

Disk settings

For each disk, you can keep the original disk settings, or you can rename the disk.

You can’t choose a disk size. Each disk keeps its source size, rounded up to the next whole GiB when needed. See Restore support notes. To resize a disk, resize it after Eon promotes the VM (see Wait for promotion).

Start the restore job

Click Restore to start the asynchronous restore job.

You can monitor the restore job on the Restore jobs tab in the Jobs page.

The job shows Complete when the VM becomes available, while disks continue hydrating in the background.

Wait for promotion

Until promotion, the VM shown in the Azure portal is the restore server. For how this works, see Instant restore in the Azure VM support notes.

Don’t restart, shut down, or stop the VM until hydration completes. If you do any of these earlier, the VM stays down until Eon support recovers it. The console doesn’t show when hydration finishes, so contact Eon support to confirm that hydration has finished before you restart, shut down, or stop the VM.

If you restore to a subscription that Eon backs up, Eon doesn’t back up the VM until promotion.

After hydration completes, the VM continues running normally. Eon promotes the VM when you restart or shut it down from its operating system, or when you stop it from the Azure portal. If you don’t restart, shut down, or stop the VM within 14 days after hydration completes, Eon doesn’t promote it. The VM keeps running nested in the restore server.

If you restart the VM, promotion briefly stops it while Eon swaps its disks and resizes it, and then Eon starts it again. If you shut down or stop the VM, it stays stopped after promotion.

During promotion, the VM runs directly on the restored disks, with the VM size you specified during restore. Eon removes the temporary management network interface and the restore server’s operating system disk. The VM keeps its name, resource ID, network interface, and private IP address. Eon sets the private IP address to static, so the VM keeps it across later stops and starts.