Azure Disk Encryption for Linux (Microsoft.Azure.Security.AzureDiskEncryptionForLinux)

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Overview

Azure Disk Encryption leverages the dm-crypt subsystem in Linux to provide full disk encryption on select Azure Linux distributions. This solution is integrated with Azure Key Vault to manage disk encryption keys and secrets.

Prerequisites

For a full list of prerequisites, see Azure Disk Encryption for Linux VMs, specifically the following sections:

Extension Schema

There are two versions of extension schema for Azure Disk Encryption (ADE):

  • v1.1 - A newer recommended schema that does not use Microsoft Entra properties.
  • v0.1 - An older schema that requires Microsoft Entra properties.

To select a target schema, the typeHandlerVersion property must be set equal to version of schema you want to use.

The v1.1 schema is recommended and does not require Microsoft Entra properties.

Note

The DiskFormatQuery parameter is deprecated. Its functionality has been replaced by the EncryptFormatAll option instead, which is the recommended way to format data disks at time of encryption.

{
  "type": "extensions",
  "name": "[name]",
  "apiVersion": "2019-07-01",
  "location": "[location]",
  "properties": {
        "publisher": "Microsoft.Azure.Security",
        "type": "AzureDiskEncryptionForLinux",
        "typeHandlerVersion": "1.1",
        "autoUpgradeMinorVersion": true,
        "settings": {
          "DiskFormatQuery": "[diskFormatQuery]",
          "EncryptionOperation": "[encryptionOperation]",
          "KeyEncryptionAlgorithm": "[keyEncryptionAlgorithm]",
          "KeyVaultURL": "[keyVaultURL]",
          "KeyVaultResourceId": "[KeyVaultResourceId]",
          "KeyEncryptionKeyURL": "[keyEncryptionKeyURL]",
          "KekVaultResourceId": "[KekVaultResourceId",
          "SequenceVersion": "sequenceVersion]",
          "VolumeType": "[volumeType]"
        }
  }
}

Schema v0.1: with Microsoft Entra ID

The 0.1 schema requires AADClientID and either AADClientSecret or AADClientCertificate.

Using AADClientSecret:

{
  "type": "extensions",
  "name": "[name]",
  "apiVersion": "2019-07-01",
  "location": "[location]",
  "properties": {
    "protectedSettings": {
      "AADClientSecret": "[aadClientSecret]",
      "Passphrase": "[passphrase]"
    },
    "publisher": "Microsoft.Azure.Security",
    "type": "AzureDiskEncryptionForLinux",
    "typeHandlerVersion": "0.1",
    "settings": {
      "AADClientID": "[aadClientID]",
      "DiskFormatQuery": "[diskFormatQuery]",
      "EncryptionOperation": "[encryptionOperation]",
      "KeyEncryptionAlgorithm": "[keyEncryptionAlgorithm]",
      "KeyEncryptionKeyURL": "[keyEncryptionKeyURL]",
      "KeyVaultURL": "[keyVaultURL]",
      "SequenceVersion": "sequenceVersion]",
      "VolumeType": "[volumeType]"
    }
  }
}

Using AADClientCertificate:

{
  "type": "extensions",
  "name": "[name]",
  "apiVersion": "2019-07-01",
  "location": "[location]",
  "properties": {
    "protectedSettings": {
      "AADClientCertificate": "[aadClientCertificate]",
      "Passphrase": "[passphrase]"
    },
    "publisher": "Microsoft.Azure.Security",
    "type": "AzureDiskEncryptionForLinux",
    "typeHandlerVersion": "0.1",
    "settings": {
      "AADClientID": "[aadClientID]",
      "DiskFormatQuery": "[diskFormatQuery]",
      "EncryptionOperation": "[encryptionOperation]",
      "KeyEncryptionAlgorithm": "[keyEncryptionAlgorithm]",
      "KeyEncryptionKeyURL": "[keyEncryptionKeyURL]",
      "KeyVaultURL": "[keyVaultURL]",
      "SequenceVersion": "sequenceVersion]",
      "VolumeType": "[volumeType]"
    }
  }
}

Property values

Note: All property values are case sensitive.

Name Value / Example Data Type
apiVersion 2019-07-01 date
publisher Microsoft.Azure.Security string
type AzureDiskEncryptionForLinux string
typeHandlerVersion 1.1, 0.1 int
(0.1 schema) AADClientID xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx guid
(0.1 schema) AADClientSecret password string
(0.1 schema) AADClientCertificate thumbprint string
(optional) (0.1 schema) Passphrase password string
DiskFormatQuery {"dev_path":"","name":"","file_system":""} JSON dictionary
EncryptionOperation EnableEncryption, EnableEncryptionFormatAll string
(optional - default RSA-OAEP ) KeyEncryptionAlgorithm 'RSA-OAEP', 'RSA-OAEP-256', 'RSA1_5' string
KeyVaultURL url string
KeyVaultResourceId url string
(optional) KeyEncryptionKeyURL url string
(optional) KekVaultResourceId url string
(optional) SequenceVersion uniqueidentifier string
VolumeType OS, Data, All string

Template deployment

For an example of template deployment based on schema v1.1, see the Azure Quickstart Template encrypt-running-linux-vm-without-aad.

For an example of template deployment based on schema v0.1, see the Azure Quickstart Template encrypt-running-linux-vm.

Warning

  • If you have previously used Azure Disk Encryption with Microsoft Entra ID to encrypt a VM, you must continue use this option to encrypt your VM.
  • When encrypting Linux OS volumes, the VM should be considered unavailable. We strongly recommend to avoid SSH logins while the encryption is in progress to avoid issues blocking any open files that will need to be accessed during the encryption process. To check progress, use the Get-AzVMDiskEncryptionStatus PowerShell cmdlet or the vm encryption show CLI command. This process can be expected to take a few hours for a 30GB OS volume, plus additional time for encrypting data volumes. Data volume encryption time will be proportional to the size and quantity of the data volumes; the encrypt format all option is faster than in-place encryption, but will result in the loss of all data on the disks.
  • Disabling encryption on Linux VMs is only supported for data volumes. It is not supported on data or OS volumes if the OS volume has been encrypted.

Note

Also if VolumeType parameter is set to All, data disks will be encrypted only if they are properly mounted.

Troubleshoot and support

Troubleshoot

For troubleshooting, refer to the Azure Disk Encryption troubleshooting guide.

Support

If you need more help at any point in this article, you can contact the Azure experts on the Azure support.

Alternatively, you can file an Azure support incident. Go to Azure support and submit your request. For information about using Azure Support, read the 21Vianet Azure Support FAQ.

Next steps