The Win32_ShadowFor class associates a shadow copy and the volume for which the shadow copy is created.
Methods
Win32_ShadowFor has no methods.
Properties
Win32_ShadowFor returns 2 properties:
'Antecedent','Dependent'
Unless explicitly marked as writeable, all properties are read-only. Read all properties for all instances:
Get-CimInstance -ClassName Win32_ShadowFor -Property *
Most WMI classes return one or more instances.
When
Get-CimInstance
returns no result, then apparently no instances of class Win32_ShadowFor exist. This is normal behavior.Either the class is not implemented on your system (may be deprecated or due to missing drivers, i.e. CIM_VideoControllerResolution), or there are simply no physical representations of this class currently available (i.e. Win32_TapeDrive).
Antecedent
Reference to an original volume.
Get-CimInstance -ClassName Win32_ShadowFor | Select-Object -Property Antecedent
Dependent
Reference to a shadow copy.
Get-CimInstance -ClassName Win32_ShadowFor | Select-Object -Property Dependent
Examples
List all instances of Win32_ShadowFor
Get-CimInstance -ClassName Win32_ShadowFor
Learn more about Get-CimInstance
and the deprecated Get-WmiObject
.
View all properties
Get-CimInstance -ClassName Win32_ShadowFor -Property *
View key properties only
Get-CimInstance -ClassName Win32_ShadowFor -KeyOnly
Selecting Properties
To select only some properties, pipe the results to Select-Object -Property a,b,c
with a comma-separated list of the properties you require. Wildcards are permitted.
Get-CimInstance
always returns all properties but only retrieves the ones that you specify. All other properties are empty but still present. That’s why you need to pipe the results into Select-Object
if you want to limit the visible properties, i.e. for reporting.
Selecting Properties
The code below lists all available properties. Remove the ones you do not need:
$properties = 'Antecedent',
'Dependent'
Get-CimInstance -ClassName Win32_ShadowFor | Select-Object -Property $properties
Limiting Network Bandwidth
If you work remotely, it makes sense to limit network bandwidth by filtering the properties on the server side, too:
Get-CimInstance -Class Win32_ShadowFor -Property $property |
Select-Object -Property $property
Selecting Instances
To select some instances, use Get-CimInstance and a WMI Query. The wildcard character in WMI Queries is % (and not “*”).
The parameter -Filter runs a simple query.
Listing all instances where the property Caption starts with “A”
Get-CimInstance -Class Win32_ShadowFor -Filter 'Caption LIKE "a%"'
Using a WQL Query
The parameter -Query uses a query similar to SQL and combines the parameters -Filter and -Property. This returns all instances where the property Caption starts with “A”, and returns the properties specified:
Get-CimInstance -Query "SELECT Dependent, Antecedent FROM Win32_ShadowFor WHERE Caption LIKE 'a%'"
Any property you did not specify is still present but empty. You might need to use
Select-Object
to remove all unwanted properties:Get-CimInstance -Query "SELECT Dependent, Antecedent FROM Win32_ShadowFor WHERE Caption LIKE 'a%'" | Select-Object -Property Dependent, Antecedent
Accessing Remote Computers
To access remote systems, you need to have proper permissions. User the parameter -ComputerName to access one or more remote systems.
Authenticating as Current User
# one or more computer names or IP addresses:
$list = 'server1', 'server2'
# authenticate with your current identity:
$result = Get-CimInstance -ClassName Win32_ShadowFor -ComputerName $list
$result
Authenticating as Different User
Use a CIMSession object to authenticate with a new identity:
# one or more computer names or IP addresses:
$list = 'server1', 'server2'
# authenticate with a different identity:
$cred = Get-Credential -Message 'Authenticate to retrieve WMI information:'
$session = New-CimSession -ComputerName $list -Credential $cred
$result = Get-CimInstance Win32_ShadowFor -CimSession $session
# remove the session after use (if you do not plan to re-use it later)
Remove-CimSession -CimSession $session
$result
Learn more about accessing remote computers.
Requirements
To use Win32_ShadowFor, the following requirements apply:
PowerShell
Get-CimInstance
was introduced with PowerShell Version 3.0, which in turn was introduced on clients with Windows 8 and on servers with Windows Server 2012.
If necessary, update Windows PowerShell to Windows PowerShell 5.1, or install PowerShell 7 side-by-side.
Operating System
Win32_ShadowFor was introduced on clients with None supported and on servers with Windows Server 2003.
Namespace
Win32_ShadowFor lives in the Namespace Root/CIMV2. This is the default namespace. There is no need to use the -Namespace parameter in Get-CimInstance
.
Implementation
Win32_ShadowFor is implemented in Vsswmi.dll and defined in Vss.mof. Both files are located in the folder C:\Windows\system32\wbem
:
explorer $env:windir\system32\wbem
notepad $env:windir\system32\wbem\Vss.mof