 It is Microsoft's new task-based command- line shell and scripting language designed especially for system administration.  It helps Information Technology Professionals and PowerShell users control and automate the Administration of the Windows operating system and applications that run on Windows.

 To address recurring needs (Viewing the logged Members )  To run script(s) as a scheduled task ( Running a command when user login or logoff)  To store and share ideas behind the scripts (Creating and modifying files and folders)  Automate repetitive tasks (Automate the user session time)

 Presently, Microsoft Windows programmers have several options when it comes to scripting. They can use: 1.MS-DOS (or CMD) to create simple batch files 2.VBScript for more complex programming 3.PowerShell to make the most of the.NET framework  With one of the above or a combination of all, a programmer gets complete control of all of the objects on a Windows computer.

 A cmdlet is a lightweight command that is used in the Windows PowerShell environment.  Cmdlets follow a verb-noun naming pattern. Examples of verbs: get, set, new Examples of nouns: service, item, date

 Below are sample Cmdlets following the verb- noun naming pattern: PS C:\>get-childitem C:\ (Gets the items and child items in one or more specified locations.) PS C:\>get-service (Retrieve information about the services installed on your computer.) PS C:\>set-location D:\ ( It enables you to specify a new working location.) PS C:\> set-location “c:\my documents”

 Get-Help (get-help set-* gives all cmdlets that start with Set-.)  Get-Command (you’ll get back a list of all the Windows PowerShell cmdlets)  Get-Member (will enumerate the properties and methods of that object.)  Get-Psdrive (Gets the Windows PowerShell drives in the current session)  Format-List (each property is displayed on a separate line)

They differ from commands used in other command-shell environments in that:  They are instances of.NET Framework classes; they are not stand-alone executables.  They can be created from as few as a dozen lines of code.  They do not usually do their own parsing, error presentation, or output formatting. All these are handled by the Windows PowerShell runtime.  They process input objects from the pipeline rather than from streams of text, and cmdlets typically deliver objects as output to the pipeline.  They are record-oriented because they process a single object at a time.

 An alias is an alternative name assigned to a Cmdlet.  Aliases allow users to quickly interact with the shell.  The Cmdlet get-alias is used to list all built- in aliases as shown in the diagram on the next slide:

 They are.NET programs used to provide easy access to information external to the shell environment in order for the users to view it and manage it.  To obtain a listing of all the providers, the Get-PSProvider cmdlet is used.  To work with specific providers, use the set- location cmdlet then specify the provider drive.

 There are seven types of providers namely: 1. Alias - Provides access to the windows PowerShell aliases and their values Get-PSProvider Sl Alias:\ GCI | where-object {$_.name –like “s*”} 2. Environment - Provides access to the Windows environment variables. 3. FileSystem - Provides access to files and directories. 4. Function - Provides access to the functions defined in Windows PowerShell.

5. Registry Provides access to the system registry keys and values. 6. Variable Provides access to Windows PowerShell variables and their values. 7. Certificate Provides read-only access to certificate stores and certificates.

Scripting support is disabled by default in Windows PowerShell. Running a script when policy is not set generates an error message that must be fixed to allow script execution.

 There are four levels of execution policy: 1. Restricted Will not run scripts or configuration files 2. AllSigned All scripts and configuration files must be signed by a trusted publisher 3. RemoteSigned All scripts and configuration files downloaded from the internet must be signed by a trusted publisher 4. Unrestricted All scripts and configuration files will run

 Use the Get-ExecutionPolicy cmdlet to retrieve the current effective script execution policy.  Use the Set-ExecutionPolicy cmdlet to change the script execution policy to unrestricted as shown below: Set-ExecutionPolicy unrestricted

 Running a script can be done either within or outside PowerShell.  Running the script within PowerShell requires the following steps: 1.Type the full path to the script 2.Include the name of the script 3.Ensure you include the PS1 extension C:\mytest\RetrieveAndSortServiceState.PS1

 Running scripts outside PowerShell requires the following steps: 1.Type the full path to the script 2.Include the name of the script 3.Ensure you include the PS1 extension 4.Feed this to the PowerShell.exe program 5.Use the –noexit argument to keep the PowerShell console after script execution Powershell –noexit C:\mytest\RetrieveAndSortServiceState.PS1

Powershell evaluates the condition at the start of each cycle and if it’s true, then it executes the command block as shown in the loop below: $wmi = get-wmiObject win32_processor if ($wmi.Architecture -eq 0) {"This is an x86 computer"} elseif($wmi.architecture -eq 1) {"This is an MIPS computer"} elseif($wmi.architecture -eq 2) {"This is an Alapha computer"} elseif($wmi.architecture -eq 3) {"This is an PowerPC computer"} elseif($wmi.architecture -eq 6) {"This is an IPF computer"} elseif($wmi.architecture -eq 9) {"This is an x64 computer"} else {$wmi.architecture + " is not a cpu type I am familiar with"} "Current clockspeed is : " + $wmi.CurrentClockSpeed + " MHZ" "Max clockspeed is : " + $wmi.MaxClockSpeed + " MHZ" "Current load percentage is: " + $wmi.LoadPercentage + " Percent" "The L2 cache size is: " + $wmi.L2CacheSize + " KB"

 They enable users to write a script that can choose from a series of options without writing a long series of If statements as shown below: $wmi = get-wmiobject win32_computersystem "computer " + $wmi.name + " is: " switch ($wmi.domainrole) { 0 {"`t Stand alone workstation"} 1 {"`t Member workstation"} 2 {"`t Stand alone server"} 3 {"`t Member server"} 4 {"`t Back up domain controller"} 5 {"`t Primary domain controller"} default {"`t The role can not be determined"} }

 Files and Folders New-Item is a quick and easy way to create a new file or folder on your computer. Creating a file: New-Item c:\scripts\new_file.txt - type file Creating a folder: New-Item c:\scripts\Windows PowerShell -type directory

$intFolders = 10 $intPad $i = 1 New-Variable -Name strPrefix -Value "testFolder" -Option constant do { if ($i -lt 10) {$intPad=0 new-item -path c:\mytest -name $strPrefix$intPad$i -type directory} else {new-item -path c:\mytest -name $strPrefix$i -type directory} $i++ }until ($i -eq $intFolders+1)

$intFolders = 10 $intPad $i = 1 New-Variable -Name strPrefix -Value "testFolder" - Option constant do { if ($i -lt 10) {$intPad=0 Remove-item -path c:\mytest\$strPrefix$intPad$i} else {Remove-item -path c:\mytest\$strPrefix$i} $i++ }until ($i -eq $intFolders+1)

 Wilson, E. (2007). Microsoft Windows PowerShell step by step. Washington: Microsoft Press.  Tomsho, G. (2010). MCTS guide to Microsoft Windows Server 2008 Active Directory configuration: Exam Boston, MA: Course Technology/Cengage Learning.  Schwichtenberg, H. (2008). Essential PowerShell. The Addison-Wesley Microsoft technology series. Upper Saddle River, NJ: Addison-Wesley.