Ondrej Žilinec – IT Blog

I was playing today with new feature called PowerShell Web Access. This feature was brought in Windows Server 2012. It is very easy to install and easy to use. You need to select one server which will act as Web Access PowerShell gateway server. You will be connecting to this server using SSL and this server will use PowerShell remoting to access computers inside your network. So let’s make it work.

First you need to run PowerShell as a admin on gateway server:

Let’s look for Windows features which contain word “shell”:

Windows PowerShell Web Access is the feature we want to install. So let’s install it:

Now we can look at this website to lear more, but let’s play more. Now we have new cmdlets containig word “pswa” (PowerShell Web Access):

We installed pswa feature, but this feature didn’t install its web component into the server. So let’s install pswa Web application using cmdlet Install-PswaWebApplication with parameter -UseTestCertificate. This parameter creates self-signed SSL certificate for this new site, you can use your own certificate. Be aware that this certificate expires in 90 days.

New website was created:

By default no one can use Powershell access gateway. You need to define explicit rules who, where and what can do. For easy test you can use following rule for domain group called GRP_PowerShell_Remote to access all computers with all permissions:

Now everything is prepared. We need to make some changes in network (routers and NAT) to be able to access 443 port on server from Internet. Now when we open site, we can see:

And now you can work on machines inside your network. It’s secure and reliable:

This is very nice and cute feature.

I hope you will start to use and enjoy it.

Have a nice day.

Sometimes you need to run some command on remote computer. If you don’t want to bother user using Remote Assistance or user is not at the computer you can try Remote Powershell. Powershell was new feature when Windows Vista and Windows Server 2008 came. So we can divide operating systems into three categories. Each category requires some things and some requirements.

Windows 7 / Windows Server 2008 R2 and higher

• Needs to open ports in firewall (is your firewall is not open all the way)
• Needs to enable and configure WinRM
• Needs to configure WinRM service to run

Windows Vista / Windows Server 2008

• Needs everything from first group
• Needs to install PowerShell 2.0

Windows XP / Windows Server 2003

• Needs everything from second group
• Needs to install .NET Framework

Probably your environment will be mixed of all three types of operating systems. So let’s look how to configure it. I will use GPOs everywhere it can be used.

Enable Remote PowerShell for Windows Vista and Windows Server 2008

Create GPO and set following:

Computer Configuration > Policies > Administrative Templates > Windows Components > Windows Remote Management (WinRM) > WinRM Service > Allow automatic configuration of listeners (Allow Remote Server management through WinRM):

Firewall exceptions

Firewall exceptions for Windows 7 / Windows Server 2008 and higher

If you have Microsoft firewall closed and you need to make exception using GPO in Computer Configuration > Policies > Administrative Templates > Network > Network Connections > Windows Firewall > Domain Profile > Windows Firewall: Define inbound port exceptions:

Firewall exceptions for Windows XP / Windows Server 2003

You have to define New Firewall rule under Computer Configuration > Policies > Windows Settings > Security Settings > Windows Firewall with Advanced Security > Windows Firewall with Advanced Security > Inbound Rules and create new Inbound rule with predefined type “Windows Remote Management”:

Configure Service

To enable Remote Powershell I need to configure service. WinRM service has to start automatically. Create new setting in GPO in Computer Configuration > Policies > Windows Settings > Security Settings > System Services. Setup service Windows Remote Management (WS-Management) following way:

Let’s change startup for this service using GPO settings under Computer Configuration > Preferences > Control Panel Settings > Services. Create new Service setting with following settings:

Windows XP / Windows 2003 specialities

To make Powershell work remotely on older operating systems you need to make sure your operating systems have installed two hotfixes: KB968930 and KB951847. These hotfixes are distibuted via Windows Updates so if you use WSUS, there updates are already on your older operating systems.

To enable PowerShell for remote connection you need to enable it using startup script. So you need to create new GPO which will run only on older OS. You can use following WMI filter to make this GPO apply only on older OS:

You can use following script as a startup script to enable Powershell Remote for Windows XP.

To test it you can run following command:

Enter-PSSession -ComputerName COMPUTER_NAME

Active Directory Users and Computes Implementation

To make it look better you can implement connection to computer using Active Directory Users and Computers.

On location \\domain.local\NETLOGON create new Powershell.vbs file:

' ' Script to run Remote Powershell on domain computer '

Set wshArguments = WScript.Arguments Set objComputer = GetObject(wshArguments(0))

' ' Check if Remote Assistance is installed '

Set fso = CreateObject("Scripting.FileSystemObject") 
If (fso.FileExists("C:\Windows\system32\WindowsPowerShell\v1.0\powershell.exe")) Then  
' Is istalled  
   Set objShell = WScript.CreateObject("WScript.Shell")  
   Return = objShell.Run("C:\Windows\system32\WindowsPowerShell\v1.0\powershell.exe -noexit \\domain.local\NETLOGON\Remote_Session.ps1" & objComputer.dNsHostName, 1, false) 
Else  
   ' Is not installed, error.  
   Wscript.Echo "Microsoft Remote PowerShell is not enabled on this machine." 
End If

On location \\domain.local\NETLOGON create new Remote_Session.ps1 file:

[CmdletBinding()]
Param(
  [Parameter(Mandatory=$True,Position=1)]
   [string]$computerName
)

Enter-PSSession -ComputerName $computername

 When files are ready, you need to create new record in Active Directory using adsiedit.msc. Connecto to configuration partition of your domain:

Go to Configuration > CN=Configuration,DC… > CN=DisplaySpecifiers > CN=409 > CN=computer-Display and edit property called adminContextMenu.

Add another record into existing list of records. I used following record:

3, &PowerShell Remote,\\domain.local\NETLOGON\Powershell.vbs

which means:

3 – order of record in the list of records (if you have only one existing record, your number will be 2)

&PowerShell Remote – name of the item in context menu

\\domain.local\NETLOGON\Powershell.vbs – path to vbs script you created

Here is how it looks in one of the environments:

When all is done, your Active Directory Users and Computers console has to be reopened and you will find new record under computer account:

When you click on this new item in context menu new powershell window opens. This powershell window is remote powershell windows from remote computer.

I hope people start using powershell more often,