Ondrej Žilinec – IT Blog

Sometimes I need to run some command on bunch of computers. So I’ve created little bit more advanced function to be able to run script block on computers list created from domain:

<#
.Synopsis
   This function provides you way to run scriptblock on remote machines in the domain.
.DESCRIPTION
   This function is extension to Cmd-Let Invoke-Command. This function lists computer names in domain
   based on ADSearchBase and Filter parameters. In invoke scriptblock on those computers in the list.
.EXAMPLE
   To restart service "Windows Time" on all machines in domain:
   Invoke-CommandOnADComputers -SearchBase "DC=domain,DC=local" -ScriptBlock { Restart-Service W32Time; }
.EXAMPLE
   To restart service "Windows Time" on all machines which containt number 7 in name:
   Invoke-CommandOnADComputers -SearchBase "DC=domain,DC=local" -Filter 'Name -like "*7*"' -ScriptBlock { Restart-Service W32Time; }
#>

Function Invoke-CommandOnADComputers
{
    [CmdletBinding(SupportsShouldProcess=$True,ConfirmImpact='Low')]
    Param
    (
        # This is Active Directory Search Base to limit selection for computer accounts in domain.
        # It can be for example "OU=Computers,OU=Company Name,DC=domain,DC=local"
        [parameter(Mandatory=$true)]
        [string]
        $SearchBase,

        # Active Directory filter to merge your computer selection in to the detail.
        # It can be for example 'Name -like "Desktop*"'
        [string]
        $Filter = "*",

        # This is scriptblock which should be run on every computer.
        # For example { Restart-Service W32Time; }
        [parameter(Mandatory=$true)]
        [scriptblock]
        $ScriptBlock
    )
    Begin
    {
        #
        # Get list of computer accounts
        #
        Write-Verbose "Getting list of computer from $ADSear"
        try
        {
            [array]$ADComputersList = Get-ADComputer -SearchBase $SearchBase -Filter $Filter -ErrorAction Stop
        }
        catch
        {
            Write-Error -Message "Couldn't search in $SearchBase" -ErrorAction Stop
        }
        #
        # Write number of found computers
        #
        Write-Host "Found $($ADComputersList.Count) computers"
        #
        # If in debug, write list of computers
        #
        Write-Verbose "List of machines:"
        If (!$PSDebugContext)
        {
            foreach ($item in $ADComputersList)
            {
                Write-Verbose " $($item.Name)"
            }
        }
        Write-Verbose "Done with domain computer list"
    }
    Process
    {
        #
        # Let's invoke command on remote computer
        #
        foreach ($ADComputer in $ADComputersList)
        {
            Write-Host $ADComputer.Name
                try
                {
                    Write-Verbose "Invoking scriptblock on computer"
                    Invoke-Command -ComputerName $ADComputer.Name -ScriptBlock { $ScriptBlock } -ErrorAction Stop
                    Write-Host " Scriptblock invoked successful."
                }
                catch
                {
                    Write-Host " Scriptblock invoked UNSUCCESSFUL."
                }
        }
    }
}

You can run it using

Invoke-CommandOnADComputers -SearchBase “DC=domain,DC=local” -ScriptBlock { Restart-Service W32Time; }

and it will read all computer accounts from domain and restart Windows Time service.

Enjoy,

I’m creating couple powershell scripts which I use in my work. I want to share couple of them with you. So here is a script which look for domain computers and then check who is logged on those online machines.

$ADSearchBase = "OU=Computers,DC=domain,DC=local"
$ADFilter = "*"

Function Get-LoggedUsersOnComputers
  {
  $ADComputersList = Get-ADComputer -SearchBase $ADSearchBase -Filter $ADFilter
  foreach ($ADComputer in $ADComputersList)
    {
    Write-Output $ADComputer.Name
    Try
       {
       $ExplorerProcesses = Get-WmiObject -ComputerName $ADComputer.Name -Class win32_process -Filter "Name='explorer.exe'" -ErrorAction Stop
       }
     Finally
       {
       If ($?)
         {
         foreach ($ExplorerProcess in $ExplorerProcesses)
           {
           Write-Output "  $($ExplorerProcess.GetOwner().User)"
           }
         }
       Else
         {
         Write-Output "  <<< Could not connect"
         }
       }
    }
  }

Get-LoggedUsersOnComputers

If you have any remark on my script, please, let me know. I will be happy to make it more cute 🙂

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,

There is lots of great tools in Linux which are needed in Windows environment. One of the great tool from linux is “tail”. You can use it following way:

tail -f /var/log/mail.log

You will get end of the file and you see all content added to file on screen. You can view log files without need to reopen it. In Windows I use utility Trace32.exe. I was looking for some more native way to do it in Windows. There is a cmd-let Get-Content in Powershell which you can use following way:

Get-Content C:\Windows\WindowsUpdate.log -Wait -Tail 10

This tails only 10 lines from the end of the file and “waits” for new added lines. Switch “Tail” is accessible only in PowerShell 3 and higher.

Powershell is getting there,

Installation of WSUS on Windows Server 2012

I started to install WSUS service on Windows Server 2012. I selected to install Windows Internal Database as store of WSUS metadata.

I selected to store updates on local C:\ drive (it’s just testing machine):

After first run on Windows Server Update Services management tool WSUS asks again if I want to store updates locally or not:

When I click Run, post-installation starts to run:

And I received Post-installation “notification” 🙂 in Microsoft word it means I have a problem (Failed to restart the current database. The currecnt database is switched to master):

So if computer has problem with restarting database, let’s restart service. Didn’t help 🙂 Let’s restart whole computer. Didn’t help either. So the problem will be somewhere else.

I tried to install WSUS from scratch. I uninstalled WSUS and also Windows Internal Database feature. I also deleted data for Windows Internal Database from directory C:\Windows\WID. Then I installed WSUS with all dependecies – WID, IIS, …

Now I’m getting different error:

Problem was backslash in input window for defining directory to store updates 😀 This path was predefined by wizard and it was wrong. This is really funny 🙂

So after reinstallation of WSUS and WID and defining “correct” path to update store directory (without backslash on the end 🙂 ) everything looks to be done correctly:

Let click Close and look what’s new in WSUS. First we need to configure WSUS and I did it using WSUS Wizard. I don’t see any news in this Wizard compared to older one.

Exploring WSUS

I haven’t notice any news in WSUS mmc console. I always use client side group targeting. This feature allows you to create groups of computers in WSUS structure. It can be used to target updates specified for testing to just group of computers and so on. To make this working you need to set client side of group targeting by defining name of Group and also you need to create new Computer Group in WSUS structure. What I always forget it to create these Computer Groups in WSUS structure 🙂 I would love to see some option to allow WSUS to create these Computer Groups automatically. But this didn’t happend of this version of WSUS.

I think the most powerful thing Microsoft added into WSUS is support for Powershell cmd-lets. Most of the time WSUS settings about update Classifications and update Products are same from customer to cutosmer, so you can automate this settings using cmd-lets Get-WsusClassification, Set-WsusClassification, Get-WsusProduct and Set-WsusProduct.

To get some information about WSUS Server it selft you can use cmd-let Get-WsusServer:

There are more interesting cmd-lets. One is Get-WsusComputer which prints out some more information about computer reported into WSUS:

Get-WsusComputer has lot of ability to filter out computers on some conditions. Failed, Needed, …

To manage updates from powershell you can use cmd-lets Get-WsusUpdate, Approve-WsusUpdate and Deny-WsusUpdate. You can for example approve all updates that are Unapproved and FailedOrNeeded:

Get-WsusUpdate -Classification All -Approval Unapproved -Status FailedOrNeeded | Approve-WsusUpdate -Action Install -TargetGroupName “All Computers”

And the last cmd-let I really love, because I can make scheduled task to run Clean-up Wizard. Cmd-let is Invoke-WsusServerCleanup. You can do every cleanup task you can make from GUI.

Conclusion

I don’t think there is too much to improve on WSUS, but little powershell support for WSUS is handy.

What a cool command in PowerShell 🙂 It doesn’t even ask if you are sure 😀 Boooooooooom….server rebooted.

We have Exchange 2007 environment which contains 6 Failover Exchange clusters and each with 24 mailbox databases (total 144 mailbox databases). When there is a problem with replication of databases we needed to click every Failover cluster and check Copy Status of databases. To get rid of this hassle I wrote little script which lists all databases which Copy Status is not “Healthy”:

Get-MailboxServer | % { Get-StorageGroupCopyStatus -Server $_.Identity | ? {$_.SummaryCopyStatus -NotLike “Healthy” } }

For Exchange 2010 it would change little bit to:

Get-MailboxServer | % { Get-MailboxDatabaseCopyStatus -Server $_.Identity | ? {$_.Status -NotLike “Healthy” } }

Now I’m ready to check in couple of seconds the health of databases 🙂

At one of our customer I was asked if there is any tool to make some statistics out of Exchange mailflow. You can use GUI Microsoft Exchange Tracking Log Explorer. This tool it usefull unless you need to make some smarter data handling. This tool doesn’t count how many mails user sent or received. Even those data displayed on the end are not exportable.

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