Windows system drive letter is assumed

[lukasfazik]

Description

Windows contextualization script context.ps1 assumes that Windows system partition drive letter is "C:". This is in most cases true, but the drive letter can be changed or it rarely changes during some system restore/recovery operations.

To Reproduce

• Prepare fresh virtual machine
• Install Windows 10, but do not finish OOBE (Out of box experience)
• Boot to audit mode by pressing CTRL + ALT + F3 on first page of OOBE
• Install OpenNebula contextualization package
• Ensure the Windows partition is the last one on the system drive
  • If that's not the case, remove Windows RE partition at the end of the drive or shrink the Windows partition
• Run command prompt as Administrator
• Export the registry key HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices by using the following command:
  • reg export HKLM\SYSTEM\MountedDevices C:\registry_backup.reg
• Change the C: drive letter to something other in C:\registry_backup.reg file
  • Recommend opening notepad as administrator in command prompt window
    • notepad C:\registry_backup.reg
• Run the Windows Sysprep tool with the following parameters:
  • %WINDIR%\system32\sysprep\sysprep.exe /generalize /quit /oobe
• Import the changed registry file using the following command:
  • reg import C:\registry_backup.reg
• Reboot the virtual machine and finish the OOBE (Out of the box experience)
• Expand the system drive in OpenNebula
• Change some contextualization parameters to trigger the contextualization
  • Example: Add variable TEMP with some value to the context
• Wait at least 30+ seconds for context to pick up the changes and rerun the contextualization
• Check that Windows partition has not been expanded by contextualization-script

Expected behavior

• Contextualization script should resize the Windows partition even if it's drive letter is different from default drive letter C:

Recommendation

• Environmental variable SYSTEMDRIVE should be used instead of C:

Details

• Affected Component: context-windows
• Version: 6.10.0-2

Additional context

• Microsoft documentation for changing the drive letter: https://learn.microsoft.com/en-us/troubleshoot/windows-server/backup-and-storage/restore-system-boot-drive-letter
• OpenNebula context log representing the issue: opennebula-context.log

Progress Status

• Code committed
• Testing - QA
• Documentation (Release notes - resolved issues, compatibility, known issues)