Map non-NVMe disks on Amazon EC2 Windows instance to volumes

List non-NVMe disks

You can find the disks on your Windows instance using Disk Management or PowerShell.

Disk Management

To find the disks on your Windows instance

1. Log in to your Windows instance using Remote Desktop. For more information, see Connect to your Windows instance using RDP.

2. Start the Disk Management utility.

   On the taskbar, right-click the Windows logo, and then choose Disk Management.

3. Review the disks. The root volume is an EBS volume mounted as C:\. If there are no other disks shown, then you didn't specify additional volumes when you created the AMI or launched the instance.

   The following is an example that shows the disks that are available if you launch an m3.medium instance with an instance store volume (Disk 2) and an additional EBS volume (Disk 1).

   

4. Right-click the gray pane labeled Disk 1, and then select Properties. Note the value of Location and look it up in the tables in Map non-NVMe disks to volumes. For example, the following disk has the location Bus Number 0, Target Id 9, LUN 0. According to the table for EBS volumes, the device name for this location is xvdj.

   

PowerShell

The following PowerShell script lists each disk and its corresponding device name and volume.

Requirements and limitations

• Requires Windows Server 2012 or later.

• Requires credentials to get the EBS volume ID. You can configure a profile using the Tools for PowerShell, or attach an IAM role to the instance.

• Does not support NVMe volumes.

• Does not support dynamic disks.

Connect to your Windows instance and run the following command to enable PowerShell script execution.

Set-ExecutionPolicy RemoteSigned

Copy the following script and save it as mapping.ps1 on your Windows instance.

# List the disks
function Convert-SCSITargetIdToDeviceName {
  param([int]$SCSITargetId)
  If ($SCSITargetId -eq 0) {
    return "sda1"
  }
  $deviceName = "xvd"
  If ($SCSITargetId -gt 25) {
    $deviceName += [char](0x60 + [int]($SCSITargetId / 26))
  }
  $deviceName += [char](0x61 + $SCSITargetId % 26)
  return $deviceName
}

[string[]]$array1 = @()
[string[]]$array2 = @()
[string[]]$array3 = @()
[string[]]$array4 = @()

Get-WmiObject Win32_Volume | Select-Object Name, DeviceID | ForEach-Object {
  $array1 += $_.Name
  $array2 += $_.DeviceID
}

$i = 0
While ($i -ne ($array2.Count)) {
  $array3 += ((Get-Volume -Path $array2[$i] | Get-Partition | Get-Disk).SerialNumber) -replace "_[^ ]*$" -replace "vol", "vol-"
  $array4 += ((Get-Volume -Path $array2[$i] | Get-Partition | Get-Disk).FriendlyName)
  $i ++
}

[array[]]$array = $array1, $array2, $array3, $array4

Try {
  $InstanceId = Get-EC2InstanceMetadata -Category "InstanceId"
  $Region = Get-EC2InstanceMetadata -Category "Region" | Select-Object -ExpandProperty SystemName
}
Catch {
  Write-Host "Could not access the instance Metadata using AWS Get-EC2InstanceMetadata CMDLet.
Verify you have AWSPowershell SDK version '3.1.73.0' or greater installed and Metadata is enabled for this instance." -ForegroundColor Yellow
}
Try {
  $BlockDeviceMappings = (Get-EC2Instance -Region $Region -Instance $InstanceId).Instances.BlockDeviceMappings
  $VirtualDeviceMap = (Get-EC2InstanceMetadata -Category "BlockDeviceMapping").GetEnumerator() | Where-Object { $_.Key -ne "ami" }
}
Catch {
  Write-Host "Could not access the AWS API, therefore, VolumeId is not available.
Verify that you provided your access keys or assigned an IAM role with adequate permissions." -ForegroundColor Yellow
}

Get-disk | ForEach-Object {
  $DriveLetter = $null
  $VolumeName = $null
  $VirtualDevice = $null
  $DeviceName = $_.FriendlyName

  $DiskDrive = $_
  $Disk = $_.Number
  $Partitions = $_.NumberOfPartitions
  $EbsVolumeID = $_.SerialNumber -replace "_[^ ]*$" -replace "vol", "vol-"
  if ($Partitions -ge 1) {
    $PartitionsData = Get-Partition -DiskId $_.Path
    $DriveLetter = $PartitionsData.DriveLetter | Where-object { $_ -notin @("", $null) }
    $VolumeName = (Get-PSDrive | Where-Object { $_.Name -in @($DriveLetter) }).Description | Where-object { $_ -notin @("", $null) }
  }
  If ($DiskDrive.path -like "*PROD_PVDISK*") {
    $BlockDeviceName = Convert-SCSITargetIdToDeviceName((Get-WmiObject -Class Win32_Diskdrive | Where-Object { $_.DeviceID -eq ("\\.\PHYSICALDRIVE" + $DiskDrive.Number) }).SCSITargetId)
    $BlockDeviceName = "/dev/" + $BlockDeviceName
    $BlockDevice = $BlockDeviceMappings | Where-Object { $BlockDeviceName -like "*" + $_.DeviceName + "*" }
    $EbsVolumeID = $BlockDevice.Ebs.VolumeId
    $VirtualDevice = ($VirtualDeviceMap.GetEnumerator() | Where-Object { $_.Value -eq $BlockDeviceName }).Key | Select-Object -First 1
  }
  ElseIf ($DiskDrive.path -like "*PROD_AMAZON_EC2_NVME*") {
    $BlockDeviceName = (Get-EC2InstanceMetadata -Category "BlockDeviceMapping").ephemeral((Get-WmiObject -Class Win32_Diskdrive | Where-Object { $_.DeviceID -eq ("\\.\PHYSICALDRIVE" + $DiskDrive.Number) }).SCSIPort - 2)
    $BlockDevice = $null
    $VirtualDevice = ($VirtualDeviceMap.GetEnumerator() | Where-Object { $_.Value -eq $BlockDeviceName }).Key | Select-Object -First 1
  }
  ElseIf ($DiskDrive.path -like "*PROD_AMAZON*") {
    if ($DriveLetter -match '[^a-zA-Z0-9]') {
      $i = 0
      While ($i -ne ($array3.Count)) {
        if ($array[2][$i] -eq $EbsVolumeID) {
          $DriveLetter = $array[0][$i]
          $DeviceName = $array[3][$i]
        }
        $i ++
      }
    }
    $BlockDevice = ""
    $BlockDeviceName = ($BlockDeviceMappings | Where-Object { $_.ebs.VolumeId -eq $EbsVolumeID }).DeviceName
  }
  ElseIf ($DiskDrive.path -like "*NETAPP*") {
    if ($DriveLetter -match '[^a-zA-Z0-9]') {
      $i = 0
      While ($i -ne ($array3.Count)) {
        if ($array[2][$i] -eq $EbsVolumeID) {
          $DriveLetter = $array[0][$i]
          $DeviceName = $array[3][$i]
        }
        $i ++
      }
    }
    $EbsVolumeID = "FSxN Volume"
    $BlockDevice = ""
    $BlockDeviceName = ($BlockDeviceMappings | Where-Object { $_.ebs.VolumeId -eq $EbsVolumeID }).DeviceName
  }
  Else {
    $BlockDeviceName = $null
    $BlockDevice = $null
  }
  New-Object PSObject -Property @{
    Disk          = $Disk;
    Partitions    = $Partitions;
    DriveLetter   = If ($DriveLetter -eq $null) { "N/A" } Else { $DriveLetter };
    EbsVolumeId   = If ($EbsVolumeID -eq $null) { "N/A" } Else { $EbsVolumeID };
    Device        = If ($BlockDeviceName -eq $null) { "N/A" } Else { $BlockDeviceName };
    VirtualDevice = If ($VirtualDevice -eq $null) { "N/A" } Else { $VirtualDevice };
    VolumeName    = If ($VolumeName -eq $null) { "N/A" } Else { $VolumeName };
    DeviceName    = If ($DeviceName -eq $null) { "N/A" } Else { $DeviceName };
  }
} | Sort-Object Disk | Format-Table -AutoSize -Property Disk, Partitions, DriveLetter, EbsVolumeId, Device, VirtualDevice, DeviceName, VolumeName

Run the script as follows:

PS C:\> .\mapping.ps1

The following is example output.

Disk  Partitions  DriveLetter   EbsVolumeId             Device      VirtualDevice   DeviceName              VolumeName
----  ----------  -----------   -----------             ------      -------------   ----------              ----------
   0           1            C   vol-0561f1783298efedd   /dev/sda1   N/A             NVMe Amazon Elastic B   N/A
   1           1            D   vol-002a9488504c5e35a   xvdb        N/A             NVMe Amazon Elastic B   N/A
   2           1            E   vol-0de9d46fcc907925d   xvdc        N/A             NVMe Amazon Elastic B   N/A

If you did not provide your credentials on the Windows instance, the script cannot get the EBS volume ID and uses N/A in the EbsVolumeId column.

Map non-NVMe disks to volumes

The block device driver for the instance assigns the actual volume names when mounting volumes.

Mappings

• Instance store volumes
• EBS volumes

Instance store volumes

The following table describes how the Citrix PV and AWS PV drivers map non-NVMe instance store volumes to Windows volumes. The number of available instance store volumes is determined by the instance type. For more information, see Instance store volume limits for Amazon EC2 instances.

Location	Device name
Bus Number 0, Target ID 78, LUN 0	xvdca
Bus Number 0, Target ID 79, LUN 0	xvdcb
Bus Number 0, Target ID 80, LUN 0	xvdcc
Bus Number 0, Target ID 81, LUN 0	xvdcd
Bus Number 0, Target ID 82, LUN 0	xvdce
Bus Number 0, Target ID 83, LUN 0	xvdcf
Bus Number 0, Target ID 84, LUN 0	xvdcg
Bus Number 0, Target ID 85, LUN 0	xvdch
Bus Number 0, Target ID 86, LUN 0	xvdci
Bus Number 0, Target ID 87, LUN 0	xvdcj
Bus Number 0, Target ID 88, LUN 0	xvdck
Bus Number 0, Target ID 89, LUN 0	xvdcl

EBS volumes

The following table describes how the Citrix PV and AWS PV drivers map non-NVME EBS volumes to Windows volumes.

Location	Device name
Bus Number 0, Target ID 0, LUN 0	/dev/sda1
Bus Number 0, Target ID 1, LUN 0	xvdb
Bus Number 0, Target ID 2, LUN 0	xvdc
Bus Number 0, Target ID 3, LUN 0	xvdd
Bus Number 0, Target ID 4, LUN 0	xvde
Bus Number 0, Target ID 5, LUN 0	xvdf
Bus Number 0, Target ID 6, LUN 0	xvdg
Bus Number 0, Target ID 7, LUN 0	xvdh
Bus Number 0, Target ID 8, LUN 0	xvdi
Bus Number 0, Target ID 9, LUN 0	xvdj
Bus Number 0, Target ID 10, LUN 0	xvdk
Bus Number 0, Target ID 11, LUN 0	xvdl
Bus Number 0, Target ID 12, LUN 0	xvdm
Bus Number 0, Target ID 13, LUN 0	xvdn
Bus Number 0, Target ID 14, LUN 0	xvdo
Bus Number 0, Target ID 15, LUN 0	xvdp
Bus Number 0, Target ID 16, LUN 0	xvdq
Bus Number 0, Target ID 17, LUN 0	xvdr
Bus Number 0, Target ID 18, LUN 0	xvds
Bus Number 0, Target ID 19, LUN 0	xvdt
Bus Number 0, Target ID 20, LUN 0	xvdu
Bus Number 0, Target ID 21, LUN 0	xvdv
Bus Number 0, Target ID 22, LUN 0	xvdw
Bus Number 0, Target ID 23, LUN 0	xvdx
Bus Number 0, Target ID 24, LUN 0	xvdy
Bus Number 0, Target ID 25, LUN 0	xvdz