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WMI and CIM

Do you know the difference between WMI and CIM?

CIM is the Common Information Model - http://www.dmtf.org/standards/cim

“CIM provides a common definition of management information for systems, networks, applications and services, and allows for vendor extensions. CIM's common definitions enable vendors to exchange semantically rich management information between systems throughout the network.”

 

WMI is Microsoft’s implementation of CIM

Get-WmiObject CIM_DiskDrive
Get-WmiObject Win32_DiskDrive

return the same information

Win32_DiskDrive is derived from CIM_DiskDrive.  The CIM class is the superclass for the Win32 class.

Why is this important?

Because in PowerShell v3 Microsoft introduce a while new API for working with WMI -  and whole new bunch of cmdlets

Get-CimAssociatedInstance
Get-CimClass
Get-CimInstance
Get-CimSession
Invoke-CimMethod
New-CimInstance
New-CimSession
New-CimSessionOption
Register-CimIndicationEvent
Remove-CimInstance
Remove-CimSession
Set-CimInstance

compare these to the WMI cmdlets

Get-WmiObject
Invoke-WmiMethod
Register-WmiEvent
Remove-WmiObject
Set-WmiInstance

The analogous CIM cmdlets are highlighted.

The CIM cmdlets use different .NET classes to WMI cmdlets

PS> Get-WmiObject Win32_DiskDrive | gm


   TypeName: System.Management.ManagementObject#root\cimv2\Win32_DiskDrive

 

PS> Get-CimInstance Win32_DiskDrive | gm


   TypeName: Microsoft.Management.Infrastructure.CimInstance#root/cimv2/Win32_DiskDrive

 

Microsoft have made a big investment in WMI/CIM for Windows 8.  I’ll explore some of the new things in coming posts

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