Disconnect-PSSession

Disconnects from a session.

Syntax

Disconnect-PSSession
          [-Session] <PSSession[]>
          [-IdleTimeoutSec <Int32>]
          [-OutputBufferingMode <OutputBufferingMode>]
          [-ThrottleLimit <Int32>]
          [-WhatIf]
          [-Confirm]
          [<CommonParameters>]
Disconnect-PSSession
          [-IdleTimeoutSec <Int32>]
          [-OutputBufferingMode <OutputBufferingMode>]
          [-ThrottleLimit <Int32>]
          -Name <String[]>
          [-WhatIf]
          [-Confirm]
          [<CommonParameters>]
Disconnect-PSSession
          [-IdleTimeoutSec <Int32>]
          [-OutputBufferingMode <OutputBufferingMode>]
          [-ThrottleLimit <Int32>]
          -InstanceId <Guid[]>
          [-WhatIf]
          [-Confirm]
          [<CommonParameters>]
Disconnect-PSSession
          [-IdleTimeoutSec <Int32>]
          [-OutputBufferingMode <OutputBufferingMode>]
          [-ThrottleLimit <Int32>]
          [-Id] <Int32[]>
          [-WhatIf]
          [-Confirm]
          [<CommonParameters>]

Description

This cmdlet is only available on the Windows platform.

The Disconnect-PSSession cmdlet disconnects a PowerShell session (PSSession), such as one started by using the New-PSSession cmdlet, from the current session. As a result, the PSSession is in a disconnected state. You can connect to the disconnected PSSession from the current session or from another session on the local computer or a different computer.

The Disconnect-PSSession cmdlet disconnects only open PSSessions that are connected to the current session. Disconnect-PSSession cannot disconnect broken or closed PSSessions, or interactive PSSessions started by using the Enter-PSSession cmdlet, and it cannot disconnect PSSessions that are connected to other sessions.

To reconnect to a disconnected PSSession, use the Connect-PSSession or Receive-PSSession cmdlets.

When a PSSession is disconnected, the commands in the PSSession continue to run until they complete, unless the PSSession times out or the commands in the PSSession are blocked by a full output buffer. To change the idle timeout, use the IdleTimeoutSec parameter. To change the output buffering mode, use the OutputBufferingMode parameter You can also use the InDisconnectedSession parameter of the Invoke-Command cmdlet to run a command in a disconnected session.

For more information about the Disconnected Sessions feature, see about_Remote_Disconnected_Sessions.

This cmdlet is introduced in Windows PowerShell 3.0.

Examples

Example 1 - Disconnect a session by name

This command disconnects the UpdateSession PSSession on the Server01 computer from the current session. The command uses the Name parameter to identify the PSSession.

PS> Disconnect-PSSession -Name UpdateSession
Id Name            ComputerName    State         ConfigurationName     Availability
-- ----            ------------    -----         -----------------     ------------
1  UpdateSession   Server01        Disconnected  Microsoft.PowerShell          None

The output shows that the attempt to disconnect was successful. The session state is Disconnected and the Availability is None, which indicates that the session is not busy and can be reconnected.

Example 2 - Disconnect a session from a specific computer

This command disconnects the ITTask PSSession on the Server12 computer from the current session. The ITTask session was created in the current session and connects to the Server12 computer. The command uses the Get-PSSession cmdlet to get the session and the Disconnect-PSSession cmdlet to disconnect it.

PS> Get-PSSession -ComputerName Server12 -Name ITTask |
  Disconnect-PSSession -OutputBufferingMode Drop -IdleTimeoutSec 86400
Id Name            ComputerName    State         ConfigurationName     Availability
-- ----            ------------    -----         -----------------     ------------
1  ITTask          Server12        Disconnected  ITTasks               None

The Disconnect-PSSession command uses the OutputBufferingMode parameter to set the output mode to Drop. This setting ensures that the script that is running in the session can continue to run even if the session output buffer is full. Because the script writes its output to a report on a file share, other output can be lost without consequence.

The command also uses the IdleTimeoutSec parameter to extend the idle timeout of the session to 24 hours. This setting allows time for this administrator or other administrators to reconnect to the session to verify that the script ran and troubleshoot if needed.

Example 3 - Using multiple PSSessions on multiple computers

This series of commands shows how the Disconnect-PSSession cmdlet might be used in an enterprise scenario. In this case, a new technician starts a script in a session on a remote computer and runs into a problem. The technician disconnects from the session so that a more experienced manager can connect to the session and resolve the problem.

PS> $s = New-PSSession -ComputerName Srv1, Srv2, Srv30 -Name ITTask
PS> Invoke-Command $s -FilePath \\Server01\Scripts\Get-PatchStatus.ps1
PS> Get-PSSession -Name ITTask -ComputerName Srv1 | Disconnect-PSSession
Id Name            ComputerName    State         ConfigurationName     Availability
-- ----            ------------    -----         -----------------     ------------
1 ITTask           Srv1            Disconnected  Microsoft.PowerShell          None

PS> Get-PSSession -ComputerName Srv1, Srv2, Srv30 -Name ITTask
Id Name            ComputerName    State         ConfigurationName     Availability
-- ----            ------------    -----         -----------------     ------------
 1 ITTask          Srv1            Disconnected  Microsoft.PowerShell          None
 2 ITTask          Srv2            Opened        Microsoft.PowerShell     Available
 3 ITTask          Srv30           Opened        Microsoft.PowerShell     Available

PS> Get-PSSession -ComputerName Srv1 -Name ITTask -Credential Domain01\User01
Id Name            ComputerName    State         ConfigurationName     Availability
-- ----            ------------    -----         -----------------     ------------
 1 ITTask          Srv1            Disconnected  Microsoft.PowerShell          None

PS> $s = Connect-PSSession -ComputerName Srv1 -Name ITTask -Credential Domain01\User01
PS> Invoke-Command -Session $s {dir $HOME\Scripts\PatchStatusOutput.ps1}
PS> Invoke-Command -Session $s {mkdir $HOME\Scripts\PatchStatusOutput}
PS> Invoke-Command -Session $s -FilePath \\Server01\Scripts\Get-PatchStatus.ps1
PS> Disconnect-PSSession -Session $s

The technician begins by creating sessions on several remote computers and running a script in each session. The first command uses the New-PSSession cmdlet to create the ITTask session on three remote computers. The command saves the sessions in the $s variable. The second command uses the FilePath parameter of the Invoke-Command cmdlet to run a script in the sessions in the $s variable.

The script running on the Srv1 computer generates unexpected errors. The technician contacts his manager and asks for assistance. The manager directs the technician to disconnect from the session so he can investigate.The second command uses the Get-PSSession cmdlet to get the ITTask session on the Srv1 computer and the Disconnect-PSSession cmdlet to disconnect it. This command does not affect the ITTask sessions on the other computers.

The third command uses the Get-PSSession cmdlet to get the ITTask sessions. The output shows that the ITTask sessions on the Srv2 and Srv30 computers were not affected by the command to disconnect.

The manager logs on to his home computer, connects to his corporate network, starts PowerShell, and uses the Get-PSSession cmdlet to get the ITTask session on the Srv1 computer. He uses the credentials of the technician to access the session.

Next, the manager uses the Connect-PSSession cmdlet to connect to the ITTask session on the Srv1 computer. The command saves the session in the $s variable.

The manager uses the Invoke-Command cmdlet to run some diagnostic commands in the session in the $s variable. He recognizes that the script failed because it did not find a required directory. The manager uses the MkDir function to create the directory, and then he restarts the Get-PatchStatus.ps1 script and disconnects from the session.The manager reports his findings to the technician, suggests that he reconnect to the session to complete the tasks, and asks him to add a command to the Get-PatchStatus.ps1 script that creates the required directory if it does not exist.

Example 4 - Change the timeout value for a PSSession

This example shows how to correct the value of the IdleTimeout property of a session so that it can be disconnected.

The idle timeout property of a session is critical to disconnected sessions, because it determines how long a disconnected session is maintained before it is deleted. You can set the idle timeout option when you create a session and when you disconnect it. The default values for the idle timeout of a session are set in the $PSSessionOption preference variable on the local computer and in the session configuration on the remote computer. Values set for the session take precedence over values set in the session configuration, but session values cannot exceed quotas set in the session configuration, such as the MaxIdleTimeoutMs value.

PS> $Timeout = New-PSSessionOption -IdleTimeout 172800000
PS> $s = New-PSSession -Computer Server01 -Name ITTask -SessionOption $Timeout
PS> Disconnect-PSSession -Session $s
Disconnect-PSSession : The session ITTask cannot be disconnected because the specified
idle timeout value 172800(seconds) is either greater than the server maximum allowed
43200 (seconds) or less that the minimum allowed60(seconds).  Choose an idle time out
value that is within the allowed range and try again.

PS> Invoke-Command -ComputerName Server01 {Get-PSSessionConfiguration Microsoft.PowerShell} |
 Format-List -Property *

Architecture                  : 64
Filename                      : %windir%\system32\pwrshplugin.dll
ResourceUri                   : http://schemas.microsoft.com/powershell/microsoft.powershell
MaxConcurrentCommandsPerShell : 1000
UseSharedProcess              : false
ProcessIdleTimeoutSec         : 0
xmlns                         : http://schemas.microsoft.com/wbem/wsman/1/config/PluginConfiguration
MaxConcurrentUsers            : 5
lang                          : en-US
SupportsOptions               : true
ExactMatch                    : true
RunAsUser                     :
IdleTimeoutms                 : 7200000
PSVersion                     : 3.0
OutputBufferingMode           : Block
AutoRestart                   : false
SecurityDescriptorSddl        : O:NSG:BAD:P(A;;GA;;;BA)S:P(AU;FA;GA;;;WD)(AU;SA;GXGW;;;WD)
MaxMemoryPerShellMB           : 1024
MaxIdleTimeoutms              : 2147483647
Uri                           : http://schemas.microsoft.com/powershell/microsoft.powershell
SDKVersion                    : 2
Name                          : microsoft.powershell
XmlRenderingType              : text
Capability                    : {Shell}
RunAsPassword                 :
MaxProcessesPerShell          : 15
ParentResourceUri             : http://schemas.microsoft.com/powershell/microsoft.powershell
Enabled                       : true
MaxShells                     : 25
MaxShellsPerUser              : 25
Permission                    : BUILTIN\Administrators AccessAllowed
PSComputerName                : localhost
RunspaceId                    : aea84310-6dbf-4c21-90ac-13980039925a
PSShowComputerName            : True


PS> $s.Runspace.ConnectionInfo
ConnectionUri                     : http://Server01/wsman
ComputerName                      : Server01
Scheme                            : http
Port                              : 80
AppName                           : /wsman
Credential                        :
ShellUri                          : http://schemas.microsoft.com/powershell/Microsoft.PowerShell
AuthenticationMechanism           : Default
CertificateThumbprint             :
MaximumConnectionRedirectionCount : 5
MaximumReceivedDataSizePerCommand :
MaximumReceivedObjectSize         : 209715200
UseCompression                    : True
NoMachineProfile                  : False
ProxyAccessType                   : None
ProxyAuthentication               : Negotiate
ProxyCredential                   :
SkipCACheck                       : False
SkipCNCheck                       : False
SkipRevocationCheck               : False
NoEncryption                      : False
UseUTF16                          : False
OutputBufferingMode               : Drop
IncludePortInSPN                  : False
Culture                           : en-US
UICulture                         : en-US
OpenTimeout                       : 180000
CancelTimeout                     : 60000
OperationTimeout                  : 180000
IdleTimeout                       : 172800000

PS> Disconnect-PSSession $s -IdleTimeoutSec 43200
Id Name            ComputerName    State         ConfigurationName     Availability
-- ----            ------------    -----         -----------------     ------------
 4 ITTask          Server01        Disconnected  Microsoft.PowerShell          None

PS> $s.Runspace.ConnectionInfo.IdleTimeout
43200000

The first command uses the New-PSSessionOption cmdlet to create a session option object. It uses the IdleTimeout parameter to set an idle timeout of 48 hours (172800000 milliseconds). The command saves the session option object in the $Timeout variable.

The second command uses the New-PSSession cmdlet to create the ITTask session on the Server01 computer. The command save the session in the $s variable. The value of the SessionOption parameter is the 48-hour idle timeout in the $Timeout variable.

The third command disconnects the ITTask session in the $s variable. The command fails because the idle timeout value of the session exceeds the MaxIdleTimeoutMs quota in the session configuration. Because the idle timeout is not used until the session is disconnected, this violation can go undetected while the session is in use.

The fourth command uses the Invoke-Command cmdlet to run a Get-PSSessionConfiguration command for the Microsoft.PowerShell session configuration on the Server01 computer. The command uses the Format-List cmdlet to display all properties of the session configuration in a list.The output shows that the MaxIdleTimeoutMS property, which establishes the maximum permitted IdleTimeout value for sessions that use the session configuration, is 43200000 milliseconds (12 hours).

The fifth command gets the session option values of the session in the $s variable. The values of many session options are properties of the ConnectionInfo property of the Runspace property of the session.The output shows that the value of the IdleTimeout property of the session is 172800000 milliseconds (48 hours), which violates the MaxIdleTimeoutMs quota of 12 hours in the session configuration.To resolve this conflict, you can use the ConfigurationName parameter to select a different session configuration or use the IdleTimeout parameter to reduce the idle timeout of the session.

The sixth command disconnects the session. It uses the IdleTimeoutSec parameter to set the idle timeout to the 12-hour maximum.

The seventh command gets the value of the IdleTimeout property of the disconnected session, which is measured in milliseconds. The output confirms that the command was successful.

Parameters

-Confirm

Prompts you for confirmation before running the cmdlet.

Type:SwitchParameter
Aliases:cf
Position:Named
Default value:False
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Id

Disconnects from sessions with the specified session ID. Type one or more IDs (separated by commas), or use the range operator (..) to specify a range of IDs.

To get the ID of a session, use the Get-PSSession cmdlet. The instance ID is stored in the ID property of the session.

Type:Int32[]
Position:1
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:False

-IdleTimeoutSec

Changes the idle timeout value of the disconnected PSSession. Enter a value in seconds. The minimum value is 60 (1 minute).

The idle timeout determines how long the disconnected PSSession is maintained on the remote computer. When the timeout expires, the PSSession is deleted.

Disconnected PSSessions are considered to be idle from the moment that they are disconnected, even if commands are running in the disconnected session.

The default value for the idle timeout of a session is set by the value of the IdleTimeoutMs property of the session configuration. The default value is 7200000 milliseconds (2 hours).

The value of this parameter takes precedence over the value of the IdleTimeout property of the $PSSessionOption preference variable and the default idle timeout value in the session configuration. However, this value cannot exceed the value of the MaxIdleTimeoutMs property of the session configuration. The default value of MaxIdleTimeoutMs is 12 hours (43200000 milliseconds).

Type:Int32
Position:Named
Default value:60
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-InstanceId

Disconnects from sessions with the specified instance IDs.

The instance ID is a GUID that uniquely identifies a session on a local or remote computer. The instance ID is unique, even across multiple sessions on multiple computers.

To get the instance ID of a session, use the Get-PSSession cmdlet. The instance ID is stored in the InstanceID property of the session.

Type:Guid[]
Position:Named
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:False

-Name

Disconnects from sessions with the specified friendly names. Wildcards are permitted.

To get the friendly name of a session, use the Get-PSSession cmdlet. The friendly name is stored in the Name property of the session.

Type:String[]
Position:Named
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:True

-OutputBufferingMode

Determines how command output is managed in the disconnected session when the output buffer is full. The default value is Block.

If the command in the disconnected session is returning output and the output buffer fills, the value of this parameter effectively determines whether the command continues to run while the session is disconnected. A value of Block suspends the command until the session is reconnected. A value of Drop allows the command to complete, although data might be lost. When using the Drop value, redirect the command output to a file on disk.

Valid values are:

  • Block: When the output buffer is full, execution is suspended until the buffer is clear.
  • Drop: When the output buffer is full, execution continues. As new output is saved, the oldest output is discarded.
  • None: No output buffering mode is specified. The value of the OutputBufferingMode property of the session configuration is used for the disconnected session.
Type:OutputBufferingMode
Position:Named
Default value:Block
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Session

Disconnects from the specified PSSessions. Enter PSSession objects, such as those that the New-PSSession cmdlet returns. You can also pipe a PSSession object to Disconnect-PSSession.

The Get-PSSession cmdlet can get all PSSessions that terminate at a remote computer, including PSSessions that are disconnected and PSSessions that are connected to other sessions on other computers. Disconnect-PSSession disconnects only PSSession that are connected to the current session. If you pipe other PSSessions to Disconnect-PSSession, the Disconnect-PSSession command fails.

Type:PSSession[]
Position:1
Default value:None
Required:True
Accept pipeline input:True
Accept wildcard characters:False

-ThrottleLimit

Sets the throttle limit for the Disconnect-PSSession command.

The throttle limit is the maximum number of concurrent connections that can be established to run this command. If you omit this parameter or enter a value of 0, the default value, 32, is used.

The throttle limit applies only to the current command, not to the session or to the computer.

Type:Int32
Position:Named
Default value:32
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-WhatIf

Shows what would happen if the cmdlet runs. The cmdlet is not run.

Type:SwitchParameter
Aliases:wi
Position:Named
Default value:False
Required:False
Accept pipeline input:False
Accept wildcard characters:False

Inputs

PSSession

You can pipe a session to this cmdlet.

Outputs

PSSession

This cmdlet returns an object representing the session that it disconnected.

Notes

PowerShell includes the following aliases for Disconnect-PSSession:

  • Windows:
    • dnsn

This cmdlet is only available on Windows platforms.

  • The Disconnect-PSSession cmdlet works only when the local and remote computers are running PowerShell 3.0 or later.

  • If you use the Disconnect-PSSession cmdlet on a disconnected session, the command has no effect on the session and it does not generate errors.

  • Disconnected loopback sessions with interactive security tokens (those created with the EnableNetworkAccess parameter) can be reconnected only from the computer on which the session was created. This restriction protects the computer from malicious access.

  • When you disconnect a PSSession, the session state is Disconnected and the availability is None.

    The value of the State property is relative to the current session. Therefore, a value of Disconnected means that the PSSession is not connected to the current session. However, it does not mean that the PSSession is disconnected from all sessions. It might be connected to a different session. To determine whether you can connect or reconnect to the session, use the Availability property.

    An Availability value of None indicates that you can connect to the session. A value of Busy indicates that you cannot connect to the PSSession because it is connected to another session.

    For more information about the values of the State property of sessions, see RunspaceState Enumeration.

    For more information about the values of the Availability property of sessions, see RunspaceAvailability Enumeration.