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10 cool things you can do with Windows PowerShell

If PowerShell's learning curve has kept you from embracing it for daily use, "cool" might not be a word you'd associate with it. But PowerShell is here to stay. It's a core part of Exchange 2007, Windows Server 2008, and SQL Server 2008, and it has immense power worth tapping into. Here are some examples of how to put PowerShell to work.

If PowerShell's learning curve has kept you from embracing it for daily use, "cool" might not be a word you'd associate with it. But PowerShell is here to stay. It's a core part of Exchange 2007, Windows Server 2008, and SQL Server 2008, and it has immense power we all need to grasp.

I'm going to put some fun into the PowerShell arena and show you a few tricks that will definitely come in handy. Besides, it is always cooler when you amaze someone with the solution from the command line. Having someone watch you right-click and fix something doesn't have the same appeal.

Note: Be careful, very careful

Yes, this is a tool worthy of the name. PowerShell can easily cause massive configuration changes, positive or negative -- so protect yourself and establish a test environment for your learning experiences. Also consider using the "-confirm" parameter to test configurations before execution for certain commands.

This information is also available as a PDF download.

#1: Report all of the USB devices installed

PowerShell is Windows Management Instrumentation (WMI) aware. From PowerShell, you can make a WMI call to retrieve the USB devices installed in a local or remote system:

gwmi Win32_USBControllerDevice -computername SERVER1 |fl Antecedent,Dependent

This will apply a filter to bring back the antecedent and dependent fields from the SERVER1 computer. Should you want the full export, you can omit the pipe and filter statement to have a comprehensive export of the USB devices on a system. I have found this useful to maintain a report for servers that have a USB license device installed so that their connectivity is maintained from the device perspective.

#2: Perform your favorite CMD tasks in PowerShell

Yes, you can stop using the DOS prompt and start doing all of those same tasks within PowerShell. This can make learning a little easier and help you become more familiar with the interface. Unfortunately, from the run prompt, there is no three-letter launcher like cmd. But powershell will launch it. You can also assign a shortcut key to PowerShell so Ctrl + Shift + P launches it directly.

#3: Kill a process in PowerShell instead of Task Manager

When you have a Windows service running that will not respond to stop commands, you can use PowerShell to perform the equivalent actions of ending the task within Task Manager. For instance, you'd do the following for BadThread.exe:

get-process BadTh*

The results will be similar to this:

Handles  NPM(K)    PM(K)      WS(K) VM(M)   CPU(s)     Id ProcessName
-------  ------    -----      ----- -----   ------     -- -----------
28       4  -210844    -201128  -163    25.67   2792 BadThread

Once the Process ID has been identified, you can kill the errant process by entering:

stop-process -id 2792

At that point, the BadThread example will be hard stopped and you can resume your attempt to start the service. You can do that right here in PowerShell as well.

#4: Use PSDrive to view more than just drives

The PSDrive command lets you view objects of the Windows environment beyond traditional network, local, or removable drives. One popular view is the HKLM PSDrive to view the HKEY_LOCAL_MACHINE top-level hive of the registry. To get into the registry, enter the following command:

PS    C:>        cd HKLM:
PS    HKLM:/>

You are then transported into the registry hive and can view and even delete items, should you wish.

#5: Export NTFS folder permissions -- recursive or not

Managing NTFS permissions is a whole separate matter, but with PowerShell, you can export the permissions to audit access or take a quick look at access control lists (ACLs) for the security configuration. This can be a great accountability mechanism to run in a scripted format periodically -- or you can run it on demand to diagnose a particular issue. For example, take the following iteration:

PS    E:>Get-Acl N:Data

This will give you a quick report of your security rights to the specified path (note that it won't give the share access). That alone is nothing too exciting, as it will report only the single specified path, but if you want to include recursion for the entire path, you can use other strategies. For the same path (N:\Data), you'd use the Get-ChildItem command (cmdlet) within PowerShell, combined with the Get-Acl command. Consider the following example:

PS    E:>Get-ChildItem N:Data -recurse | Get-Acl

This will span the entire N:\Data path and display the ACLs for the contents of the path. What happens here is that the Get-ChildItem provides an inventory of the file system objects, and that collection is passed to Get-Acl to provide the results for each item.

If you want to archive this to a comma-separated variable (CSV) document, you pass "| export-csv c:\filename.csv" at the end of the cmdlet. You can also pass the normal "> C:\filename.txt" to the end of the command to get it exported to a text file. Note that when you use the -recurse option, it does just that and will traverse the entire path you specify. So be careful when doing it across a large volume or over the network.

#6: Play with PowerShell 2.0

PowerShell 2.0 is in the Community Technology Preview (CTP) stage. It includes a graphical interface, Graphical PowerShell, and it is cool. The PowerShell scripts are saved as .ps1 files, making it easy to modify, import, and transfer scripts across systems. Figure A shows our NTFS permissions example while running in the graphical mode.

Figure A

One note on PowerShell 2.0: You have to configure the execution policy through PowerShell (nongraphical version) before using the tool. Configure one of the following execution policies:

PS C:>Set-ExecutionPolicy Restricted      (check only)
PS C:>Set-ExecutionPolicy AllSigned       (most secure)
PS C:>Set-ExecutionPolicy RemoteSigned    (medium secure)
PS C:>Set-ExecutionPolicy Unrestricted    (least secure)

When deciding to evaluate PowerShell 2.0, note that the WS-MAN v1.1 package is required, and if you want to use the graphical interface, Microsoft .NET Framework 3.0 is required.

#7: Work from the keyboard in Graphical PowerShell

If you are familiar with the Microsoft SQL Query Analyzer environment, you will appreciate some of these keyboard shortcuts. In Graphical PowerShell, you can select a single line or multiple lines and execute them by pressing the F5 key. Also, if you have modified your script, the familiar Ctrl + S to save, Ctrl + Z to undo, Ctrl + C to copy, and Ctrl + V to paste are available to save you time in the editing and testing.

#8: Background a time-consuming task

If you have a cmdlet that will take some time to run, you can use PowerShell to send it to the background to complete. In this way, you can send a series of commands to execute at once and let them complete on their own schedule. The command to launch a background job leads with the start-psjob -command parameter. You can query PowerShell on the status of any of the jobs with the following command:

PS C:>get-psjob
You'll see a table of results showing the current status of your jobs, with a session identifier that is unique for each job. Figure B shows one failed job.

Figure B

You can remove the failed job by running the following command:

PS C:>remove-psjob 9

#9: Insert timestamps into PowerShell outputs

For your PowerShell tasks, you can have a timestamp entered in series so you can determine how long a single step occurs or to use as a logging mechanism for your scripts. I find this handy in Graphical PowerShell when I'm testing scripts. To insert a timestamp, enter one of the following commands as a single line within your .ps1 file:

Command Output example
"$(Get-Date -format g) Start logging" 2/5/2008 9:15 PM
"$(Get-Date -format F) Start logging" Tuesday, February 05, 2008 9:15:13 PM
“$(Get-Date -format o) Start logging" 2008-02-05T21:15:13.0368750-05:00

There are many other formats for the Get-Date command, but these three options would generally suite most applications for timestamp purposes.

#10: Stop and smell the roses

Within PowerShell, some commands have results that scroll through the screen very quickly. If you are not exporting the results to a file, it may be impossible to view the onscreen interaction. Let's again use the Get-ChildItem command from previous example. This command can return many results depending on your path contents. We'll create a function called EasyView to make it easy to view the results onscreen by displaying one line every half-second. The EasyView function would be created as follows:

function EasyView { process { $_; Start-Sleep -seconds .5}}

To make a PowerShell command use the EasyView function, call it with a pipe at the end of the command and then the function name as shown below:

Get-ChildItem N:Data | EasyView

The EasyView function is configured to display lines at a half-second interval. You can also use milliseconds for the value.


Have you been experimenting with PowerShell or using it to streamline your tasks? What are some of your favorite commands?

About

Rick Vanover is a software strategy specialist for Veeam Software, based in Columbus, Ohio. Rick has years of IT experience and focuses on virtualization, Windows-based server administration, and system hardware.

15 comments
samanoze
samanoze

Well, what can I say. I am very happy reading this stuff. But what i want to know is, is there help for beginners about PowerShell out there.

igrass
igrass

Windows command line, even with PowerShell, doesn't even come close to the efficiency and power of UNIX/Linux shell commands. As a Windows Server admin and a UNIX server admin I am qualified to make that statement. Looking at the above commands for PowerShell, the syntax seems a little too clunky. Similar UNIX commands are much more streamlined. It's funny that after all these years the Windows OS is starting to incorporate Unix like commands that have existed since the late 1970's. I am glad the Microsoft is more fully embracing the power/efficiency of command driven interaction. Now if only PowerShell had a command equivalent to the power of "grep". I am not an experienced PowerShell user so if one exists please prove me wrong...

palradi602
palradi602

Jodi thanks win powersell additional information/R??#&di p??l/

chuck_crow
chuck_crow

Looks good for Windows but I wish Microsoft would get with the game and create an open solution you could use on any platform. (Windows, Linux, Mac, Unix --etc.)

b4real
b4real

On #9, the date format for the third example should be: ?$(Get-Date -format o) Start logging? 2008-02-05T21:15:13.0368750-05:00

NetMan1958
NetMan1958

Do what I did, download and install UnixUtils. It includes grep plus many other common unix utilities and they run as native Win32's do you don't have to install Cygwin first.

Neon Samurai
Neon Samurai

But they have gotten with the game. A cross platform management console would lessen the percieved switching costs of customers exercising free will to look at other solutions. Unfortunately, MS has baught and repainted the stadium then convinced everyone that it's always been the home team living there. We'll just have to wait until someone truly innovative reverse engineers the powershell protocol so we can finally manage Windows servers from any client workstation (unless you currently count rDesktop).

seanferd
seanferd

other platforms are already a "powershell".

JodyGilbert
JodyGilbert

Thanks for the catch, Rick -- I fixed it. --Jody

wratholix
wratholix

Bless open source ;) i cant live without grep/awk/sed etc. Here you can grab either individually or download the whole package with loads of linux power for your windows.

The Ref
The Ref

for a bash equivalent for windows

Neon Samurai
Neon Samurai

I do need to give Cygwin another go though. I try out the xWindows servers for win32/64 every six months or so but have never had the motivation to fight through too my prefered refined setup. For any serious work on a *nix machine I boot a VM or liveCD then go in through ssh and X natively. In general, my VMs go the other way though; *nix host with win32 guests. hehe.. your recommendation to support the point though. If your using something other than Windows for your server, there are cross platform management tools available. If your server is Windows, it does all it can to force your workstations to be Windows.

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