TOPIC
about_Session_Configurations
SHORT DESCRIPTION
Describes session configurations, which determine the users who can
connect to the computer remotely and the commands they can run.
LONG DESCRIPTION
A session configuration is a group of settings on the local computer
that define the environment for the Windows PowerShell sessions that are
created when remote users connect to the local computer.
Administrators of the computer can use session configurations to protect
the computer and to define custom environments for users who connect to
the computer.
Administrators can also use session configurations to determine the
permissions that are required to connect to the computer remotely. By
default, only members of the Administrators group have permission to
use the session configuration to connect remotely, but you can change
the default settings to allow all users, or selected users, to connect
remotely to your computer.
Session configurations are a feature of Web Services for Management
(WS-Management) based Windows PowerShell remoting. They are used only
when you use the New-PSSession, Invoke-Command, or Enter-PSSession cmdlets
to connect to a remote computer.
Note: To manage the session configurations on a computer that is running
Windows Vista, Windows Server 2008, or a later version of Windows,
start Windows PowerShell with the "Run as administrator" option.
About Session Configurations
Every Windows PowerShell session uses a session configuration. This
includes persistent sessions that you create by using the New-PSSession
or Enter-PSSession cmdlets, and the temporary sessions that Windows
PowerShell creates when you use the ComputerName parameter of a cmdlet
that uses WS-Management-based remoting technology, such as
Invoke-Command.
Administrators can use session configurations to protect the resources
of the computer and to create custom environments for users who connect
to the computer. For example, you can use a session configuration to
limit the size of objects that the computer receives in the session,
to define the language mode of the session, and to specify the cmdlets,
providers, and functions that are available in the session.
By configuring the security descriptor of a session configuration, you
determine who can use the session configuration to connect to the
computer. Users must have Execute permission to a session configuration
to use it in a session. If a user does not have the required permissions
to use any of the session configurations on a computer, the user cannot
connect to the computer remotely.
By default, only Administrators of the computer have permission to use
the default session configurations. But, you can change the security
descriptors to allow everyone, no one, or only selected users to use
the session configurations on your computer.
Default Session Configurations
Windows PowerShell includes a built-in session configuration named
Microsoft.PowerShell. On computers running 64-bit versions of Windows,
Windows PowerShell also provides Microsoft.PowerShell32, a 32-bit
session configuration.
These session configurations are used for sessions by default, that is,
when a command to create a session does not include the ConfigurationName
parameter of the New-PSSession, Enter-PSSession, or Invoke-Command
cmdlet.
The security descriptors for the default session configurations allow
only members of the Administrators group on the local computer to use
them. As such, only members of the Administrators group can connect to
the computer remotely unless you change the default settings.
You can change the default session configurations by using the
$PSSessionConfigurationName preference variable. For more information,
see about_Preference_Variables.
Viewing Session Configurations on the Local Computer
To get the session configurations on your local computer, use the
Get-PSSessionConfiguration cmdlet.
For example, type:
C:\PS> get-pssessionconfiguration | format-list -property name, permission
Name : microsoft.powershell
Permission : BUILTIN\Administrators AccessAllowed
Name : microsoft.powershell32
Permission : BUILTIN\Administrators AccessAllowed
You can also use the WS-Management provider in Windows PowerShell to view
session configurations. The WS-Management provider creates a WSMAN:
drive in your session.
In the WSMAN: drive, session configurations are in the Plugin node.
(All session configurations are in the Plugin node, but there are items
in the Plugin node that are not session configurations.)
For example, to view the session configurations on the local computer,
type:
C:\PS> dir wsman:\localhost\plugin\microsoft*
WSManConfig: Microsoft.WSMan.Management\WSMan::localhost\Plugin
Name Type Keys
---- ---- ----
microsoft.powershell Container {Name=microsoft.powershell}
microsoft.powershell32 Container {Name=microsoft.powershell}
Viewing Session Configurations on a Remote Computer
To view the session configurations on a remote computer, use the
Connect-WSMan cmdlet to add a note for the remote computer to the WSMAN:
drive on your local computer, and then use the WSMAN: drive to view
the session configurations.
For example, the following command adds a node for the Server01 remote
computer to the WSMAN: drive on the local computer.
C:\PS> connect-wsman server01.corp.fabrikam.com
When the command is complete, you can navigate to the node for the
Server01 computer to view the session configurations.
For example:
C:\PS> cd wsman:
PS WSMan:\> dir
ComputerName Type
------------ ----
localhost Container
server01.corp.fabrikam.com Container
PS WSMan:\> dir server01*\plugin\*
WSManConfig: Microsoft.WSMan.Management\WSMan::server01.corp.fabrikam.com\Plugin
Name Type Keys
---- ---- ----
microsoft.powershell Container {Name=microsoft.powershell}
microsoft.powershell32 Container {Name=microsoft.powershell32}
Changing the Security Descriptor of a Session Configuration
By default, members of the Administrators group on the computer have
Execute permission to the default session configurations, but you can
change the security descriptors on the default session configurations
and on any session configurations that you create.
To give other users permission to connect to the computer remotely,
use the Set-PSSessionConfiguration cmdlet to add "Execute" permissions
for those users to the security descriptors of the Microsoft.PowerShell
and Microsoft.PowerShell32 session configurations.
For example, the following command opens a property page that lets you
change the security descriptor for the Microsoft.PowerShell default
session configuration.
C:\PS> set-pssessionConfiguration -name Microsoft.PowerShell -showSecurityDescriptorUI
To deny everyone permission to all the session configurations on the
computer, use the Disable-PSRemoting function or the
Disable-PSSessionConfiguration cmdlet. For example, the following
command adds a "Deny All" entry to all the session configurations on the
computer.
C:\PS> disable-psremoting
To add a "Deny All" entry to a particular session configuration, use
the Disable-PSSessionConfiguration cmdlet. For example, the following
command adds a "Deny All" entry to the Microsoft.PowerShell session
configuration.
C:\PS> disable-pssessionConfiguration -name Microsoft.PowerShell
To remove the "Deny All" entry from all the session configurations, use
the Enable-PSRemoting or Enable-PSSessionConfiguration cmdlet. For
example, the following command removes the "Deny All" entry from the
default session configurations.
C:\PS> enable-pssessionConfiguration -name Microsoft.Power*
To make other changes to the security descriptor of a session
configuration, use the Set-PSSessionConfiguration cmdlet. Use the
SecurityDescriptorSDDL parameter to submit an SDDL string value. Use the
ShowSecurityDescriptorUI parameter to display a user interface property
sheet that helps you to create a new SDDL.
For example:
C:\PS> set-pssessionConfiguration -name Microsoft.PowerShell -showSecurityDescriptorUI
Creating a New Session Configuration
To create a new session configuration on the local computer, use the
Register-PSSessionConfiguration cmdlet. To define the new session
configuration, you can use a C# assembly, a Window PowerShell script,
and the parameters of the Register-PSSessionConfiguration cmdlet.
For example, the following command creates a session configuration
that is identical the Microsoft.PowerShell session configuration, except
that it limits the data received from a remote command to 20 megabytes
(MB). (The default is 50 MB).
c:\PS> register-psSessionConfiguration -name NewConfig --MaximumReceivedDataSizePerCommandMB 20
When you create a session configuration, you can manage it by using the
other session configuration cmdlets, and it appears in the WSMAN: drive.
For more information, see Register-PSSessionConfiguration.
Removing a Session Configuration
To remove a session configuration from the local computer, use the
Unregister-PSSessionConfiguration cmdlet. For example, the following
command removes the NewConfig session configuration from the computer.
c:\PS> unregister-psSessionConfiguration -name NewConfig
For more information, see Unregister-PSSessionConfiguration.
Selecting a Session Configuration
To select a particular session configuration for a session, use the
ConfigurationName parameter of New-PSSession, Enter-PSSession, or
Invoke-Command.
For example, this command uses the New-PSSession cmdlet to start a
PSSession on the Server01 computer. The command uses the
ConfigurationName parameter to select the WithProfile configuration
on the Server01 computer.
C:\PS> new-pssession -computername Server01 -configurationName WithProfile
This command will succeed only if the current user has permission to use
the WithProfile session configuration or can supply the credentials of a
user who has the required permissions.
You can also use the $PSSessionConfigurationName preference variable to
change the default session configuration on the computer. For more
information about the $PSSessionConfigurationName preference variable,
see about_Preference_Variables.
SEE ALSO
about_Preference_Variables
about_PSSession
about_Remote
New-PSSession
Disable-PSSessionConfiguration
Enable-PSSessionConfiguration
Get-PSSessionConfiguration
Register-PSSessionConfiguration
Set-PSSessionConfiguration
Unregister-PSSessionConfiguration