I need to write a function that generates an id that is unique for a given machine running a Windows OS.
Currently, I'm using WMI to query various hardware parameters and concatenate them together and hash them to derive the unique id. My question is, what are the suggested parameters I should use? Currently, I'm using a combination of bios\cpu\disk data to generate the unique id. And am using the first result if multiple results are there for each metric.
However, I ran into an issue where a machine that dual boots into 2 different Windows OS generates different site codes on each OS, which should ideally not happen.
For reference, these are the metrics I'm currently using:
Win32_Processor:UniqueID,ProcessorID,Name,Manufacturer,MaxClockSpeed
Win32_BIOS:Manufacturer
Win32_BIOS:SMBIOSBIOSVersion,IdentificationCode,SerialNumber,ReleaseDate,Version
Win32_DiskDrive:Model, Manufacturer, Signature, TotalHeads
Win32_BaseBoard:Model, Manufacturer, Name, SerialNumber
Win32_VideoController:DriverVersion, Name
Parse the SMBIOS yourself and hash it to an arbitrary length. See the PDF specification for all SMBIOS structures available.
To query the SMBIOS info from Windows you could use EnumSystemFirmwareEntries, EnumSystemFirmwareTables and GetSystemFirmwareTable.
IIRC, the "unique id" from the CPUID instruction is deprecated from P3 and newer.