PowerShell 101 – What is it And Why It matters

1. Thomas Lee (tfl@psp.co.uk) MCT and PowerShell MVP PowerShell 101 – What is itAnd Why It matters

2. What is it/Why it Matters • What IS PowerShell? • What are Cmdlets, Objects and the Pipeline? • Language fundamentals • How do I install and setup PowerShell> • How do I use PowerShell? • PowerShell profiles • Getting the most from PowerShell • Why does it matter?

3. What IS PowerShell? • PowerShell is • Microsoft’s task automation platform. • Part of Microsoft’s Common Engineering Criteria • Included with every version of Windows7/Server 2008 R2 (and as a OS patch for earlier versions) • In a couple of years, if you don’t know PowerShell you may not have a job as an IT Pro!

4. What’s IN PowerShell • Shell • Unix like (console.exe) • Lightweight IDE (sort of VS Lite) • Scripting Language • Power of Perl/Ruby • Extensible • Create your own cmdlets/providers/types/etc • Leverage the community • Built on .NET and Windows • MS-centric/MS-focused

5. PowerShell Architecture

6. Remoting with PowerShell

7. PowerShell Fundamentals Cmdlets Objects Pipeline PowerShell Language Features Discovery Community

8. What Are Cmdlets? • The fundamental unit of functionality • Implemented as a .NET Class • Get some, buy some, find some, or build your own • Cmdlets take parameters • Parameters have names (prefaced with “-”) • Parameter names can be abbreviated • Cmdlets can have aliases • Built in or add your own • Aliases do NOT include parameter aliasing 

9. What Are Objects? • A computer abstraction of a real life thing • A process • A server • An AD User • Objects have occurrences you manage • The processes running on a computer • The users in an OU • The files in a folder

10. PowerShell Object Support • PowerShell supports: • .NET objects • COM objects • WMI objects • Syntax and usage vary • So similar, yet so different • LOTS more detail – just not in this session

11. What Is The Pipeline? • Connects cmdlets • One cmdlet outputs objects • Next cmdlet uses them as input • Pipeline is not a new concept • Came From Unix/Linux • PowerShell Pipes objects not text

12. What IS the Pipeline • Connects output from a cmdlet to the input of another cmdlet • Combination of the all cmdlets etc makes a pipeline

13. The Pipeline In Action Process Object Get-Process Cmdlet Pipe Sort-Object Cmdlet PS C:>Get-Process |Sort-Object

14. Why This Design Matters • Simple to use • Just string cmdlets/scripts/functions together • Simpler to write in many cases • Very powerful in operation • Lets PowerShell do the heavy lifting • Integrates functionality stacks • OS • Application • PowerShell Base • Community

15. Discovery And Community • A key concept in PowerShell • Built-in help (Get-Help, Get-Command) • Automatic linking to online help • Huge PowerShell ecosystem – the community • Social networking: eg Twitter, Facebook, etc • Mailing lists and newsgroups • Web sites and blogs • User Groups • 3rd party support – free stuff coming!

16. Cmdlets, Objects, and the Pipeline dEMO

17. Variables • Variables contain objects during a session • Variables named starting with ‘$’ • $myvariable = 42 • Variable’s Type is implied (or explicit) • $myfoo = ls c:\foo • Variables can put objects into pipeline • $myfoo | format-table name • Variables can be reflected on • $myfoo | get-member • You can use variables in scripts and the command line

18. Built-in Variables • Some variables come with PowerShell • $PSVersionTable • $PSHome • Some variables tell PowerShell what to do • $WarningPreference • $MaximumHistoryCount • You can create variables in Profile(s) that persist • Using your profile (more later) • See variables • LS Variable:

19. Scalar Values • Scalar variable contains a single value • $i=42 • Can use properties/methods directly • $i=42; $i.tostring("p") • Use to calculate a value for use in formatting • See more in discussion on Formatting (next session)

20. Array Values • Array variables contain multiple values/objects • Array members addressed with [], e.g. $a[0] • $a[0] is first item in array • $a[-1] is last item • Use .GetType() • $myfoo = LS c:\foo • $myfoo.gettype() • Array members can be one or multiple types • LS c:\ | Get-Member • Arrays used with loops

21. Hash Table • Special type of an array • Also known as dictionary or property bag • Contains a set of key/value pairs • Values can be read automagically $ht=@{"singer"="Jerry Garcia“; "band"="Greatful Dead”} $ht.singer • Value can be another hash table! • See Get-Help about_hash_tables

22. Variable Type • Variables can be implicitly typed • PowerShell works it out by default • $I=42;$i.gettype() • Variables can be explicitly typed • [int64] $i = 42 • $i.gettype() • Typing an expression • $i = [int64] (55 – 13); $i.gettype() • $i = [int64] 55 – [int32] 13; $i.gettype() • $i = [int32] 55 – [int64] 13; $i.gettype()

23. Operators

24. More Operators

25. Special Operators

26. Expressions • Variables plus operators • Produce some value • Value can be an object too! • Simple expressions • $i+1; $j-1; $k*2, $l/4 • Boolean expression • General format is: <value> -<operator> <value> • $a –gt $b

27. Why not use > or < etc?? • History • Redirection etc a historical reality • Keep the parser simple • PowerShell does more than simple “>”!! • Case insensitive vs. case sensitive comparisons

28. What else? • Lots! • Modules • Way of managing PowerShell code in an enterprise • Remoting • 1:1 or 1:many Remoting • XML Support • Native XML • More, more, more • Attend some great training

29. Objects,Variables, Types, etc dEMO

30. How Do I Install PowerShell? • Built in to Win7, Server 2008 R2 • On Server, add ISE Feature • On Server Core PowerShell – add feature (and .NET) • Down-level operating systems • Shipped as an OS Patch with WinRM – KB 968929 • Get it from the net - http://tinyurl.com/pshr2rtm • NB: Different versions i386 vs x64, XP/Vista/2008 • No version for IA64 or Windows 2000(Or earlier) • Beware of search engine links to beta versions

31. How Do I Use PowerShell? • From the Console • Start/PowerShell • From the PowerShell ISE • Start/PowerShellISE • Part of an application • GUI layered on PowerShell • Application focused console • Third Party IDEs • PowerShell Plus • PowerGUI

32. How Do I Configure PowerShell • Add third party tools • There are lots! • Using Built-in tools • This will vary with what OS you use and which applications you are running • Configure PowerShell using Profiles

33. What are Profiles? • Special scripts that run at startup • Multiple Profiles • Per User vs. Per System • Per PowerShell Console vs. for ALL consoles • ISE profile – just for ISE • Creating a profile • Leveraging other people’s work • If you use it - stick it in your profile!

34. Common Profile Contents • Set up prompt • Function prompt {“Psh`[$(pwd)]: “} • Add personal aliases • Set-Alias gh get-help • Create PSDrives • New-PsDrive demo file e:\psh\demo • Set size/title of of PowerShell console • $host.ui.rawui.WindowTitle = "PowerShell Rocks!!!" • $host.ui.rawui.buffersize.width=120 • $host.ui.rawui.buffersize.height=9999 • $host.ui.rawui.windowsize.width=120 • $host.ui.rawui.windowsize.height=42

35. Getting More From PowerShell • Start with replacing CMD.Exe with PowerShell • Get some good training • Use shared code where possible • Use great tools • Don’t re-invent the wheel • Leverage the community

36. PowerShell Training • Official MOC • 6434 – 3 day based on PowerShell V1 • 10325 – upcoming 5 day course (due 8/10) • PowerShell Master Class • http://www.powershellmasterclass.com • New Horizons CWL • V2 course coming

37. Resources • Use your favorite search engine!!! • PowerShell Owner’s Manual • http://technet.microsoft.com/en-us/library/ee221100.aspx • PowerShell – Getting Started Guide • http://tinyurl.com/pshgsg • PowerShell references • http://www.reskit.net/psmc

38. And for your dev trainers… • PowerShell is not just an IT Pro tool • Developers need it too • Build cmdlets • Build providers • Build Management GUIs • More on this topic in some other day.

39. Let’s Summarise • PowerShell: • Combines cmdlets, objects and the pipeline • Provides a programming language and many more features we’ve not looked at today • Enables local and remote management • Is easy to get and easy to customise via profiles • Is supported by discovery and a vibrant community • PowerShell is the future of managing Windows and Windows applications

40. Now For The FREE Stuff! Sorry but this offer has now closed and the winners chosen. However, see the .scripting newsgroup for more info on both PowerShell and on an offer from Idera! • I have free copies of PowerShell Pro • Idera’s PowerShell Development Tool • The first 25 folks to email me will get a link to download the software (and a license). • I gave you the email address at the start of this presentation • The codeword is “POWERSHELLROCKS!” • The first 25 to mail that code word to the address I gave earlier will win their prixe!

41. Questions? • I will answer what I can now • More questions – email me at: tfl@psp.co.uk • Or use the .Scripting MCT newsgroup

42. The End