(PREVIEW) Azure Gen1 to Gen2 Trusted Launch VM Upgrade

Azure Generation 2 (Gen2) VM is based on UEFI-based boot architecture which enables key scenarios including Trusted Launch (TLVM). Gen2 TLVM provides customers with secure compute solutions with security capabilities like:

Feature Name Description
Secure Boot Protects OS against rootkits and boot kits.
vTPM It serves as a dedicated secure vault for keys and measurements, enabling attestation by measuring the entire boot chain of your VM
Guest VM Attestation Guest attestation extension enables proactive attestation and monitoring the boot integrity of your VMs.

Newer OS like Windows Server 2022 Azure Edition require UEFI, Windows 11 requires UEFI & vTPM as pre-requisite for installation. Additionally, for enabling Azure Compute security benchmark (like Secure Boot), UEFI support in OS is mandatory.

You can now upgrade existing Gen1 (BIOS) VMs to Trusted launch by on-boarding to preview at https://aka.ms/Gen1ToTLUpgrade. This repository provides end users with PowerShell script-based guidance which they can self-execute & upgrade existing Gen1 (BIOS) VMs to Gen2 (UEFI) VMs.

NOTE: Please review the list of Known issues before executing validation.

IMPORTANT DISCLAIMER

Production use: The Preview should only be used for testing, evaluation and feedback. Production workloads are not recommended.

Preview features are not backed with Microsoft Support SLA.

Pre-Requisites

Pre-Requisite Description
On-board subscription for preview Register for Gen1 to Trusted launch upgrade preview at https://aka.ms/Gen1ToTLUpgrade.
PowerShell version 7.2 or above Required version for parallel processing.
Az PowerShell Module Required cmdlets for Azure Platform.
VM Contributor rights on Gen1 VM resource group. Required RBAC permissions to modify and re-deploy Gen1 VM.
VM is in allocated / Running state. Required to read current state and configuration of Gen1 VM and execute MBR to GPT conversion.
Operating System Operating system should be Trusted launch supported. except
  • Windows Server 2016
NOTE:
Azure IaaS VM Agent Azure IaaS Windows VM Agent OR Azure IaaS Linux VM Agent should be installed and healthy.
Disk Encryption If enabled, Disable any OS disk encryption including Bitlocker, CRYPT, Server side encryption with customer managed keys prior to upgrade. All disk encryptions should be re-enabled post successful upgrade.
VM Backup Azure Backup if enabled for VM(s) should be configured with Enhanced Backup Policy. Trusted launch security type cannot be enabled for Generation 2 VM(s) configured with Standard Policy backup protection.
Existing Azure VM backup can be migrated from Standard to Enhanced policy using Migrate Azure VM backups from standard to enhanced policy (preview)
VM Disaster Recovery Trusted launch VMs currently do not support Azure Site Recovery (ASR). If enabled, ASR should be disabled prior to upgrade.

Best Practices

Best Practice Description
Validate in lower environment Enable Trusted launch on a test Generation 2 VM and ensure if any changes are required to meet the prerequisites before enabling Trusted launch on Generation 2 VMs associated with production workloads.
Backup Gen1 VM Create restore point for Azure Generation 1 VM(s) associated with workloads before enabling Trusted launch security type. You can use the Restore Point to re-create the disks and Generation 1 VM with the previous well-known state.
OS Disk free space You will not be able to extend OS disk system volume after MBR to GPT conversion. Recommendation is to extend system volume for future before executing Gen2-Trusted launch upgrade.
Known issues Review the Known issues before executing upgrade.

High-Level Upgrade Workflow

Id Step Description
1 Validate Pre-Requisites Validate pre-requisites for executing script:
  • Az.Account, Az.Compute PowerShell modules
  • Csv location (Refer to sampleCsv for schema details.)
2 Connect Azure Subscription and read Gen1 VM Configuration Store Gen1 VM Configuration required for conversion:
  • OS Disk Metadata
  • VM Size
3 Validate VM SKU Trusted launch Support Validate if current VM Size assigned to Gen1 VM supports Trusted launch. If not, VM Size for Gen1 VM will need to be updated with Trusted launch support.
For steps of changing VM Size, please refer to Change the size of a Virtual Machine.
4 Execute MBR to GPT conversion Script will execute online MBR to GPT conversion of OS disk boot partition.
Note: For Linux VMs following assumptions are made:
  • OS disk boot partition is mounted on /dev/sda.
  • VM is created using Azure marketplace image and not migrated from outside Azure cloud.
5 De-allocate and upgrade VM properties Script will update the VM attributes from Gen1 to Gen2 and security type to Trusted launch.
6 Start VM Post successful upgrade, VM will be started.

Script execution

Parameter Name Description Mandatory
subscriptionId Subscription ID for Gen1 VM to be upgraded. True
tenantDomain Primary AAD Domain Name for authentication. (For example, contoso.onmicrosoft.com) True
csvLocation Local file path location of csv containing vmName, vmResourceGroupName, enableSecureBoot details. True
batchSize Number of machines which should be processed in parallel. Default set to 5. False
useCloudShell Use cloud shell in Azure Portal for script execution. False
useSignedScript For environment with strict PowerShell signing requirements, Use end to end signed script for upgrade. False
outputStorageAccountName Required for useSignedScript parameter, Name of storage account where output and error file will be stored. Storage Blob Data Contributor or Storage Blob Data Owner access required on storage account. False
Csv column Name Description Mandatory
vmName Resource Name of Gen1 VM to be upgraded. True
vmResourceGroupName Resource Group for Gen1 VM to be upgraded. True
enableSecureBoot If target Trusted Launch VM should be deployed with Secure Boot enabled (TRUE) or disabled (FALSE). By default set to TRUE.
This option should be disabled if VM is hosting custom or unsigned boot drivers which cannot be attested.
False

Example

.\Upgrade-Gen1ToTL.ps1 -subscriptionId $subscriptionId -tenantDomain contoso.onmicrosoft.com -csvLocation "C:\Temp\sampleCsv.csv"
    
# Upgrade all VMs provided in csv from Gen1 to Trusted launch with specific parameter values.

Post-Conversion Activities

After successful conversion of Gen1 to Trusted Launch VM, user needs to perform required steps for applicable scenarios from below list:

  1. Validate health of Virtual Machine OS and workload hosted on converted Gen2 TLVM.
  2. Re-enable all disk encryptions on Trusted launch virtual machine post successful upgrade.

Linux OS MBR to GPT conversion

Execute these steps on Linux Gen1 VM to complete MBR to GPT conversion before executing Gen1 -> Trusted Launch upgrade script.

Note: Non-Azure steps are applicable for Non-Azure Linux VMs only, i.e., Linux VMs created outside Azure cloud. These do not apply if the Linux VM has been created in Azure Cloud.

Id Step Description
1 Query the OS Disk using below command
lsblk -o NAME,HCTL,SIZE,MOUNTPOINT | grep -i "sd"
Identify the boot partition and associated disk
Identity boot partition
2 Backup MBR partition:
dd if=/dev/sda of=backup.mbr bs=512 count=1
Backup should be taken on drive other than Boot drive.
Backup boot partition
3 Non-Azure Install EFI Package:
  • For Ubuntu: apt install grub-efi-amd64
    Note: grub-efi-amd64-signed is recommended if supported by OS configuration.
  • For RHEL: yum install gdisk grub2-x64-efi-modules efibootmgr dosfstools -y
Ubuntu grub efi
RHEL grub efi
4 Execute gdisk command gdisk /dev/sdato create new partition with following values:
  • Command: n
  • Partition Number: default
  • First Sector: 34
  • Last Sector: 2047
  • partition type ef02
  • Command: w to write the changes
Gdisk Execution
5 Update partition table changes:partprobe /dev/sda
6 Install Bootloader in re-partitioned boot disk:
  • For Ubuntu: grub-install /dev/sda
  • For RHEL & SLES grub2-install /dev/sda
grub execute
7 Non-Azure Execute gdisk to add an EFI System partition (ESP) with partition type ef00. Recommended size is +200M
Command: gdisk /dev/sda
  • Command: n
  • Partition Number: default
  • First Sector:default
  • Last Sector:+200M
  • Partition type: ef00
  • Command: w to write the changes
EF00 partition
8 Non-Azure Execute gdisk to rename above created partition to EFI-system
Command: gdisk /dev/sda
  • Command: c
  • Partition Number: From Step 7 above
  • Enter Name:EFI-system (case-sensitive)
  • Command: w to write the changes
EFI-system rename
9 Non-Azure Build vfat filesystem for ESP.
mkfs -t vfat -v /dev/disk/by-partlabel/EFI-system
Vfat ESP
10 Non-Azure If does not exists already; create ESP Mountpoint
mkdir /boot/efi
11 Copy existing files in /boot/efi to temporary /mnt/folder.
  1. mount -t vfat /dev/disk/by-partlabel/EFI-system /mnt
  2. mv /boot/efi/* /mnt
  3. umount /mnt
12 Non-Azure Add the ESP mountpoint to /etc/fstab. (replace spaces with tab key)
/dev/disk/by-partlabel/EFI-system /boot/efi vfat defaults 0 2
ESP Mount
13 Non-Azure Mount ESP
mount /boot/efi
14 Non-Azure Install the GRUB EFI bootloader.
Ubuntu/Debian:
grub-install --target=x86_64-efi /dev/sda
RHEL:
grub2-install --target=x86_64-efi /dev/sda
grub2 efi install
grub 2 efi install contd

Troubleshooting

Share the log files available under folder Gen1-Trustedlaunch-Upgrade at %userprofile% with feature team to troubleshoot Gen1 to Trusted launch upgrade.

MBR2GPT - Windows

Share following log files available at %windir% with feature team to troubleshoot failures related to MBR2GPT execution for Windows VMs:

  • setupact.log
  • setuperr.log

Known issues

CRITICAL - Windows 11 boot fails

Windows 10 Gen1 VM is successfully upgraded to Trusted launch followed by successful Windows 11 in-place upgrade. However, the Windows 11 boot fails after Azure VM is stopped and started with below error.

Windows 11 boot error

Workaround for the issue currently is to refresh the Windows 11 OS disk. For more details, Refresh Windows 11 OS disk Team is actively troubleshooting this issue.

Gen1 to Trusted launch upgrade for Linux distros

Gen1 to Trusted launch upgrade script has been validated with Ubuntu 20.04 LTS distro. For other distros, mandatorily validate the upgrade in lower environment before running in production.

Cannot find room for the EFI system partition

This error occurs for one of following reason:

  • There is no free space available on the system volume
  • System volume is corrupted. You can validate by trying to Shrink Volume by few MBs under Disk Management console. Use command chkdsk C:/v/f to repair system volume.
  • Virtual Disk Service is not running or unable to communicate successfully.
  • System volume disk is already configured with 4 MBR partitions (maximum supported by MBR disk layout). You need to delete one of the partition to make room for EFI system partition.
    1. Run ReAgentc /info to identify partition actively used by Recovery. Example: Windows RE location: \\?\GLOBALROOT\device\harddisk0\partition4\Recovery\WindowsRE
    2. Run PowerShell cmdlet Get-Partition -DiskNumber 0 to identify current partitions configured.
    3. Run PowerShell cmdlet Remove-Partition -DiskNumber 0 -PartitionNumber X to remove any extra Recovery partition not actively used by Recovery service as identified in Step 1.

D Drive assigned to System Reserved Post upgrade

Temporary storage Drive letter assignment 'D' is changed to 'E' with previous letter assigned to System Reserved post-upgrade. The issue is being troubleshooted. execute below steps manually post-upgrade to workaround the issue:

After the upgrade check the disks on the server, if system reserved partition has the letter D:, do the following actions:

  • reconfigure pagefile from D: to C:
  • reboot the server
  • remove letter D: from the partition
  • reboot the server to show the temporary storage disk with D: letter