Trusted Launch FAQ

Article
10/24/2024

Caution

This article references CentOS, a Linux distribution that's nearing end-of-life (EOL) status. Consider your use and plan accordingly. For more information, see the CentOS EOL guidance.

Frequently asked questions (FAQs) about Azure Trusted Launch feature use cases, support for other Azure features, and fixes for common errors.

Use cases

This section answers questions about use cases for Trusted Launch.

Why should I use Trusted Launch? What does Trusted Launch guard against?

Trusted Launch guards against boot kits, rootkits, and kernel-level malware. These sophisticated types of malware run in kernel mode and remain hidden from users. For example:

Firmware rootkits: These kits overwrite the firmware of the virtual machine (VM) BIOS, so the rootkit can start before the operating system (OS).
Boot kits: These kits replace the OS's bootloader so that the VM loads the boot kit before the OS.
Kernel rootkits: These kits replace a portion of the OS kernel, so the rootkit can start automatically when the OS loads.
Driver rootkits: These kits pretend to be one of the trusted drivers that the OS uses to communicate with the VM's components.

What are the differences between Secure Boot and measured boot?

In a Secure Boot chain, each step in the boot process checks a cryptographic signature of the subsequent steps. For example, the BIOS checks a signature on the loader, and the loader checks signatures on all the kernel objects that it loads, and so on. If any of the objects are compromised, the signature doesn't match and the VM doesn't boot. For more information, see Secure Boot.

How does Trusted Launch compare to Hyper-V Shielded VM?

Hyper-V Shielded VM is currently available on Hyper-V only. Hyper-V Shielded VM is typically deployed with Guarded Fabric. A Guarded Fabric consists of a Host Guardian Service (HGS), one or more guarded hosts, and a set of Shielded VMs. Hyper-V Shielded VMs are used in fabrics where the data and state of the VM must be protected from various actors. These actors are both fabric administrators and untrusted software that might be running on the Hyper-V hosts.

Trusted Launch, on the other hand, can be deployed as a standalone VM or as virtual machine scale sets on Azure without other deployment and management of HGS. All of the Trusted Launch features can be enabled with a simple change in deployment code or a checkbox on the Azure portal.

What is VM Guest State (VMGS)?

VM Guest State (VMGS) is specific to Trusted Launch VMs. It's a blob managed by Azure and contains the unified extensible firmware interface (UEFI) Secure Boot signature databases and other security information. The lifecycle of the VMGS blob is tied to that of the OS disk.

Can I disable Trusted Launch for a new VM deployment?

Trusted Launch VMs provide you with foundational compute security. We recommend that you don't disable them for new VM or virtual machine scale set deployments except if your deployments have dependency on:

You can use the securityType parameter with the Standard value to disable Trusted Launch in new VM or virtual machine scale set deployments by using Azure PowerShell (v10.3.0+) and the Azure CLI (v2.53.0+).

Note

We don't recommend disabling Secure Boot unless you're using custom unsigned kernel or drivers.

If you need to disable Secure Boot, under the VM's configuration, clear the Enable Secure Boot option.

CLI
PowerShell

az vm create -n MyVm -g MyResourceGroup --image Ubuntu2204 `
    --security-type 'Standard'

$adminUsername = <USER NAME>
$adminPassword = <PASSWORD> | ConvertTo-SecureString -AsPlainText -Force
$vmCred = New-Object System.Management.Automation.PSCredential($adminUsername, $adminPassword)
New-AzVM -Name MyVm -Credential $vmCred -SecurityType Standard

Supported features and deployments

This section discusses Trusted Launch supported features and deployments.

Is Azure Compute Gallery supported by Trusted Launch?

Trusted Launch now allows images to be created and shared through the Azure Compute Gallery (formerly Shared Image Gallery). The image source can be:

An existing Azure VM that is either generalized or specialized.
An existing managed disk or a snapshot.
A VHD or an image version from another gallery.

For more information about deploying a Trusted Launch VM by using the Azure Compute Gallery, see Deploy Trusted Launch VMs.

Is Azure Backup supported by Trusted Launch?

Trusted Launch now supports Azure Backup. For more information, see Support matrix for Azure VM backup.

Will Azure Backup continue working after I enable Trusted Launch?

Backups configured with the Enhanced policy continue to take backups of VMs after you enable Trusted Launch.

Are ephemeral OS disks supported by Trusted Launch?

Trusted Launch supports ephemeral OS disks. For more information, see Trusted Launch for ephemeral OS disks.

Note

When you use ephemeral disks for Trusted Launch VMs, keys and secrets generated or sealed by the virtual Trusted Platform Module (vTPM) after the creation of the VM might not be persisted across operations like reimaging and platform events like service healing.

Are security features available with Trusted launch applicable to data disks as well?

Trusted launch provides foundational security for Operating system hosted in virtual machine by attesting its boot integrity. Trusted launch security features are applicable for running OS and OS disks only, they are not applicable to data disks or OS binaries stored in data disks. For more details, see Trusted launch overview

Can a VM be restored by using backups taken before Trusted Launch was enabled?

Backups taken before you upgrade an existing Generation 2 VM to Trusted Launch can be used to restore the entire VM or individual data disks. They can't be used to restore or replace the OS disk only.

How can I find VM sizes that support Trusted Launch?

See the list of Generation 2 VM sizes that support Trusted Launch.

Use the following commands to check if a Generation 2 VM size doesn't support Trusted Launch.

CLI
PowerShell

subscription="<yourSubID>"
region="westus"
vmSize="Standard_NC12s_v3"

az vm list-skus --resource-type virtualMachines  --location $region --query "[?name=='$vmSize'].capabilities" --subscription $subscription

$region = "southeastasia"
$vmSize = "Standard_M64"
(Get-AzComputeResourceSku | where {$_.Locations.Contains($region) -and ($_.Name -eq $vmSize) })[0].Capabilities

The response is similar to the following form. Output that includes TrustedLaunchDisabled True indicates that the Generation 2 VM size doesn't support Trusted Launch. If it's a Generation 2 VM size and TrustedLaunchDisabled isn't part of the output, Trusted Launch is supported for that VM size.

Name                                         Value
----                                         -----
MaxResourceVolumeMB                          8192000
OSVhdSizeMB                                  1047552
vCPUs                                        64
MemoryPreservingMaintenanceSupported         False
HyperVGenerations                            V1,V2
MemoryGB                                     1000
MaxDataDiskCount                             64
CpuArchitectureType                          x64
MaxWriteAcceleratorDisksAllowed              8
LowPriorityCapable                           True
PremiumIO                                    True
VMDeploymentTypes                            IaaS
vCPUsAvailable                               64
ACUs                                         160
vCPUsPerCore                                 2
CombinedTempDiskAndCachedIOPS                80000
CombinedTempDiskAndCachedReadBytesPerSecond  838860800
CombinedTempDiskAndCachedWriteBytesPerSecond 838860800
CachedDiskBytes                              1318554959872
UncachedDiskIOPS                             40000
UncachedDiskBytesPerSecond                   1048576000
EphemeralOSDiskSupported                     True
EncryptionAtHostSupported                    True
CapacityReservationSupported                 False
TrustedLaunchDisabled                        True
AcceleratedNetworkingEnabled                 True
RdmaEnabled                                  False
MaxNetworkInterfaces                         8

How can I validate that my OS image supports Trusted Launch?

See the list of OS versions supported with Trusted Launch.

Marketplace OS images

Use the following commands to check if an Azure Marketplace OS image supports Trusted Launch.

CLI
PowerShell

az vm image show --urn "MicrosoftWindowsServer:WindowsServer:2022-datacenter-azure-edition:latest"

The response is similar to the following form. If hyperVGeneration is v2 and SecurityType contains TrustedLaunch in the output, the Generation 2 OS image supports Trusted Launch.

{
  "architecture": "x64",
  "automaticOsUpgradeProperties": {
    "automaticOsUpgradeSupported": false
  },
  "dataDiskImages": [],
  "disallowed": {
    "vmDiskType": "Unmanaged"
  },
  "extendedLocation": null,
  "features": [
    {
      "name": "SecurityType",
      "value": "TrustedLaunchAndConfidentialVmSupported"
    },
    {
      "name": "IsAcceleratedNetworkSupported",
      "value": "True"
    },
    {
      "name": "DiskControllerTypes",
      "value": "SCSI, NVMe"
    },
    {
      "name": "IsHibernateSupported",
      "value": "True"
    }
  ],
  "hyperVGeneration": "V2",
  "id": "/Subscriptions/00000000-0000-0000-0000-00000000000/Providers/Microsoft.Compute/Locations/westus/Publishers/MicrosoftWindowsServer/ArtifactTypes/VMImage/Offers/WindowsServer/Skus/2022-datacenter-azure-edition/Versions/20348.1906.230803",
  "imageDeprecationStatus": {
    "alternativeOption": null,
    "imageState": "Active",
    "scheduledDeprecationTime": null
  },
  "location": "westus",
  "name": "20348.1906.230803",
  "osDiskImage": {
    "operatingSystem": "Windows",
    "sizeInGb": 127
  },
  "plan": null,
  "tags": null
}

Get-AzVMImage -Skus 22_04-lts-gen2 -PublisherName Canonical -Offer 0001-com-ubuntu-server-jammy -Location westus3 -Version latest

You can use the output of the command with Virtual machines - Get API. The response is similar to the following form. If hyperVGeneration is v2 and SecurityType contains TrustedLaunch in the output, the Generation 2 OS image supports Trusted Launch.

{
    "properties": {
        "hyperVGeneration": "V2",
        "architecture": "x64",
        "replicaType": "Managed",
        "replicaCount": 10,
        "disallowed": {
            "vmDiskType": "Unmanaged"
        },
        "automaticOSUpgradeProperties": {
            "automaticOSUpgradeSupported": false
        },
        "imageDeprecationStatus": {
            "imageState": "Active"
        },
        "features": [
            {
                "name": "SecurityType",
                "value": "TrustedLaunchSupported"
            },
            {
                "name": "IsAcceleratedNetworkSupported",
                "value": "True"
            },
            {
                "name": "DiskControllerTypes",
                "value": "SCSI, NVMe"
            },
            {
                "name": "IsHibernateSupported",
                "value": "True"
            }
        ],
        "osDiskImage": {
            "operatingSystem": "Linux",
            "sizeInGb": 30
        },
        "dataDiskImages": []
    },
    "location": "WestUS3",
    "name": "22.04.202309080",
    "id": "/Subscriptions/00000000-0000-0000-0000-000000000000/Providers/Microsoft.Compute/Locations/WestUS3/Publishers/Canonical/ArtifactTypes/VMImage/Offers/0001-com-ubuntu-server-jammy/Skus/22_04-lts-gen2/Versions/22.04.202309080"
}

Azure Compute Gallery OS image

Use the following commands to check if an Azure Compute Gallery OS image supports Trusted Launch.

CLI
PowerShell

az sig image-definition show `
    --gallery-image-definition myImageDefinition `
    --gallery-name myImageGallery `
    --resource-group myImageGalleryRg

The response is similar to the following form. If hyperVGeneration is v2 and SecurityType contains TrustedLaunch in the output, the Generation 2 OS image supports Trusted Launch.

{
  "architecture": "x64",
  "features": [
    {
      "name": "SecurityType",
      "value": "TrustedLaunchSupported"
    }
  ],
  "hyperVGeneration": "V2",
  "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/myImageGalleryRg/providers/Microsoft.Compute/galleries/myImageGallery/images/myImageDefinition",
  "identifier": {
    "offer": "myImageDefinition",
    "publisher": "myImageDefinition",
    "sku": "myImageDefinition"
  },
  "location": "westus3",
  "name": "myImageDefinition",
  "osState": "Generalized",
  "osType": "Windows",
  "provisioningState": "Succeeded",
  "recommended": {
    "memory": {
      "max": 32,
      "min": 1
    },
    "vCPUs": {
      "max": 16,
      "min": 1
    }
  },
  "resourceGroup": "myImageGalleryRg",
  "tags": {},
  "type": "Microsoft.Compute/galleries/images"
}

Get-AzGalleryImageDefinition -ResourceGroupName myImageGalleryRg `
    -GalleryName myImageGallery -GalleryImageDefinitionName myImageDefinition

The response is similar to the following form. If hyperVGeneration is v2 and SecurityType contains TrustedLaunch in the output, the Generation 2 OS image supports Trusted Launch.

ResourceGroupName : myImageGalleryRg
OsType            : Windows
OsState           : Generalized
HyperVGeneration  : V2
Identifier        :
  Publisher       : myImageDefinition
  Offer           : myImageDefinition
  Sku             : myImageDefinition
Recommended       :
  VCPUs           :
    Min           : 1
    Max           : 16
  Memory          :
    Min           : 1
    Max           : 32
ProvisioningState : Succeeded
Id                : /subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/myImageGalleryRg/providers/Microsoft.Compute/galleries/myImageGallery/images/myImageDefinition
Name              : myImageDefinition
Type              : Microsoft.Compute/galleries/images
Location          : westus3
Tags              : {}
Features[0]       :
  Name            : SecurityType
  Value           : TrustedLaunchSupported
Architecture      : x64

How do external communication drivers work with Trusted Launch VMs?

Adding COM ports requires that you disable Secure Boot. COM ports are disabled by default in Trusted Launch VMs.

Troubleshooting issues

This section answers questions about specific states, boot types, and common boot issues.

What should I do when my Trusted Launch VM has deployment failures ?

This section provides additional details on Trusted Launch deployment failures for you to take proper action to prevent them.

Virtual machine <vm name> failed to create from the selected snapshot because the virtual Trusted Platform Module (vTPM) state is locked.
To proceed with the VM creation, please select a different snapshot without a locked vTPM state.
For more assistance, please refer to “Troubleshooting locked vTPM state” in FAQ page at https://aka.ms/TrustedLaunch-FAQ.

This deployment error happens when the snapshot or restore point provided is inaccessible or unusable for the following reasons:

Corrupt virtual machine guest state (VMGS)
vTPM in a locked state
One or more critical vTPM indices are in an invalid state.

The above can happen if a user or workload running on the virtual machine sets the lock on vTPM or modifies critical vTPM indices that leaves the vTPM in an invalid state.

Retrying with the same snapshot/restore point will result in the same failure.

To resolve this:

On the source Trusted Launch VM where the snapshot or restore point was generated, the vTPM errors must be rectified.
1. If the vTPM state was modified by a workload on the virtual machine, you need to use the same to check the error states and bring the vTPM to a non-error state.
2. If TPM tools were used to modify the vTPM state, then you should use the same tools to check the error states and bring the vTPM to a non-error state.

Once the snapshot or restore point is free from these errors, you can use this to create a new Trusted Launch VM.

Why is the Trusted Launch VM not booting correctly?

If unsigned components are detected from the UEFI (guest firmware), bootloader, OS, or boot drivers, a Trusted Launch VM won't boot. The Secure Boot setting in the Trusted Launch VM fails to boot if unsigned or untrusted boot components are encountered during the boot process and reports as a Secure Boot failure.

Screenshot that shows the Trusted Launch pipeline from Secure Boot to third-party drivers.

Note

Trusted Launch VMs that are created directly from an Azure Marketplace image should not encounter Secure Boot failures. Azure Compute Gallery images with an original image source of Azure Marketplace and snapshots created from Trusted Launch VMs should also not encounter these errors.

How would I verify a no-boot scenario in the Azure portal?

When a VM becomes unavailable from a Secure Boot failure, "no-boot" means that VM has an OS component that's signed by a trusted authority, which blocks booting a Trusted Launch VM. On VM deployment, you might see information from resource health within the Azure portal stating that there's a validation error in Secure Boot.

To access resource health from the VM configuration page, go to Resource Health under the Help pane.

If you verified that the no-boot was caused by a Secure Boot failure:

The image you're using is an older version that might have one or more untrusted boot components and is on a deprecation path. To remedy an outdated image, update to a supported newer image version.
The image you're using might have been built outside of a marketplace source or the boot components have been modified and contain unsigned or untrusted boot components. To verify whether your image has unsigned or untrusted boot components, see the following section, "Verify Secure Boot failures."
If the preceding two scenarios don't apply, the VM is potentially infected with malware (bootkit/rootkit). Consider deleting the VM and re-creating a new VM from the same source image while you evaluate all the software being installed.

Why does my Trusted Launch VM show 50MB less memory?

With Trusted Launch, an execution environment commonly known as "the paravisor" is created and runs inside the VM. Typically, about 50MB of memory is used by the paravisor and would show as "reserved" within the guest Operating System.

Verify Secure Boot failures

This section helps you verify Secure Boot failures.

Linux virtual machines

To verify which boot components are responsible for Secure Boot failures within an Azure Linux VM, you can use the SBInfo tool from the Linux Security Package.

Turn off Secure Boot.
Connect to your Azure Linux Trusted Launch VM.
Install the SBInfo tool for the distribution your VM is running. It resides within the Linux Security Package.

These commands apply to Ubuntu, Debian, and other Debian-based distributions.

echo "deb [arch=amd64] http://packages.microsoft.com/repos/azurecore/ trusty main" | sudo tee -a /etc/apt/sources.list.d/azure.list

echo "deb [arch=amd64] http://packages.microsoft.com/repos/azurecore/ xenial main" | sudo tee -a /etc/apt/sources.list.d/azure.list

echo "deb [arch=amd64] http://packages.microsoft.com/repos/azurecore/ bionic main" | sudo tee -a /etc/apt/sources.list.d/azure.list

wget https://packages.microsoft.com/keys/microsoft.asc

wget https://packages.microsoft.com/keys/msopentech.asc

sudo apt-key add microsoft.asc && sudo apt-key add msopentech.asc

sudo apt update && sudo apt install azure-security

These commands apply to RHEL, CentOS, and other Red Hat-based distributions.

echo "[packages-microsoft-com-azurecore]" | sudo tee -a /etc/yum.repos.d/azurecore.repo

echo "name=packages-microsoft-com-azurecore" | sudo tee -a /etc/yum.repos.d/azurecore.repo

echo "baseurl=https://packages.microsoft.com/yumrepos/azurecore/" | sudo tee -a /etc/yum.repos.d/azurecore.repo

echo "enabled=1" | sudo tee -a /etc/yum.repos.d/azurecore.repo

echo "gpgcheck=0" | sudo tee -a /etc/yum.repos.d/azurecore.repo

sudo yum install azure-security

These commands apply to SLES, openSUSE, and other SUSE-based distributions.

sudo zypper ar -t rpm-md -n "packages-microsoft-com-azurecore" --no-gpgcheck https://packages.microsoft.com/yumrepos/azurecore/ azurecore

sudo zypper install azure-security

After you install the Linux Security Package for your distribution, run the sbinfo command to verify which boot components are responsible for Secure Boot failures by displaying all unsigned modules, kernels, and bootloaders.

sudo sbinfo -u -m -k -b

To learn more about the SBInfo diagnostic tool, you can run sudo sbinfo -help.

Why am I getting a boot integrity monitoring fault?

Trusted Launch for Azure VMs is monitored for advanced threats. If such threats are detected, an alert is triggered. Alerts are only available if enhanced security features in Microsoft Defender for Cloud are enabled.

Microsoft Defender for Cloud periodically performs attestation. If the attestation fails, a medium-severity alert is triggered. Trusted Launch attestation can fail for the following reasons:

The attested information, which includes a log of the Trusted Computing Base (TCB), deviates from a trusted baseline (like when Secure Boot is enabled). Any deviation indicates that untrusted modules were loaded and the OS might be compromised.
The attestation quote couldn't be verified to originate from the vTPM of the attested VM. The verification failure indicates malware is present and might be intercepting traffic to the TPM.
The attestation extension on the VM isn't responding. An unresponsive extension indicates a denial-of-service attack by malware or an OS admin.

Certificates

This section provides information on certificates.

How can I establish root of trust with Trusted Launch VMs?

The virtual TPM AK public certificate provides you with visibility for information on the full certificate chain (Root and Intermediate Certificates) to help you validate trust in the certificate and root chain. To ensure that you continually have the highest security posture for Trusted Launch, it provides information on instance properties so that you can trace back to the full chain.

Download instructions

Package certificates, composed of .p7b (Full Certificate Authority) and .cer (Intermediate CA), reveal the signing and certificate authority. Copy the relevant content and use certificate tooling to inspect and assess details of certificates.

Select to download the .crt that follows for the Azure Virtual TPM Root Certificate Authority 2023

Azure Virtual TPM Root Certificate Authority 2023

Select to view the .p7b content

Global Virtual TPM CA - 01:

Select to view the .cert content for the Root Certificate

Azure Virtual TPM Root Certificate Authority 2023

Select to view the intermediate CA content

Intermediate Certificate Authority for TPM cert:

"Global Virtual TPM CA - XX" (intermediate CA) [.cer], 
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Intermediate Certificate Authority

Thumbprint # db1f3959dcce7091f87c43446be1f4ab2d3415b7
Serial Number # 3300000002c0d17b4b8f979c35000000000002
Valid Until # November 3rd, 2025

What Microsoft owned trusted certificates are built into Azure VMs ?

For Windows VMs, Windows CA certificate is built in UEFI firmware. For Linux VMs, Microsoft UEFI CA certificate is built in UEFI firmware. For Azure Linux VMs only, an additional ‘Azure Services Linux Kmod PCA’ certificate is also added in in UEFI firmware for all Linux distributions. Linux Kmod PCA is used to sign Microsoft owned kernel modules.

Linux Kmod PCA certificate is added to make customer experience smoother when using Microsoft solutions like Azure Site Recovery (ASR) which installs a kernel module. The ASR kernel module will load without any customer action to supply a key as ASR kernel module is signed using the trusted ‘Azure Services Linux Kmod PCA’ certificate.

Download instructions

Package certificates, composed of .p7b and .cer reveal the signing and certificate authority. Copy the relevant content and use certificate tooling to inspect and assess details of certificates.

Select to download the .crt that follows for the Microsoft Windows CA

Microsoft Windows CA

Select to download the .crt that follows for the Microsoft UEFI CA

Microsoft UEFI CA

Select to view the .p7b content

Azure services Linux kmod PCA certificate:

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Trusted Launch FAQ

Use cases

Why should I use Trusted Launch? What does Trusted Launch guard against?

What are the differences between Secure Boot and measured boot?

How does Trusted Launch compare to Hyper-V Shielded VM?

What is VM Guest State (VMGS)?

Can I disable Trusted Launch for a new VM deployment?

Supported features and deployments

Is Azure Compute Gallery supported by Trusted Launch?

Is Azure Backup supported by Trusted Launch?

Will Azure Backup continue working after I enable Trusted Launch?

Are ephemeral OS disks supported by Trusted Launch?

Are security features available with Trusted launch applicable to data disks as well?

Can a VM be restored by using backups taken before Trusted Launch was enabled?

How can I find VM sizes that support Trusted Launch?

How can I validate that my OS image supports Trusted Launch?

Marketplace OS images

Azure Compute Gallery OS image

How do external communication drivers work with Trusted Launch VMs?

Troubleshooting issues

What should I do when my Trusted Launch VM has deployment failures ?

Why is the Trusted Launch VM not booting correctly?

How would I verify a no-boot scenario in the Azure portal?

Why does my Trusted Launch VM show 50MB less memory?

Verify Secure Boot failures

Linux virtual machines

Why am I getting a boot integrity monitoring fault?

Certificates

How can I establish root of trust with Trusted Launch VMs?

Download instructions

What Microsoft owned trusted certificates are built into Azure VMs ?

Download instructions

Feedback

Additional resources