PowerShell: More flexible than Ipconfig

PowerShell: More flexible than Ipconfig

Scripting WMI objects with PowerShell is a particularly productive area.  On this page I will illustrate PowerShell's capabilities by creating a script which is more flexible than Ipconfig.

Topics for PowerShell: More flexible than Ipconfig

• Our Mission
• Objective 1) - List WMI Objects
• Objective 2) - WMIObject | get-Member
• Objective 3) - PowerShell: More flexible than Ipconfig

Our Mission

On this page our mission is to extract TCP/IP information from a machine's network adapters using PowerShell.  But first a question: 'Is Guy reinventing the wheel?  Can Ipconfig, with its numerous switches, provide the same information?' 

To answer this question is easy, all you have to do is compare Ipconfig with my PowerShell scripts, even better, compare Ipconfig with YOUR scripts.  If I could sum up the benefit of PowerShell over Ipconfig, in one word, that word would be flexibility.  For example, you can customize which TCP/IP properties to display, and in addition, you can interrogate the network adapters on other machines.  Can Ipconfig do that?  I have not found away.

PowerShell Objectives

WMIObject -list  (parameter to enumerate all possible object classes)
WMIObject | get-Member (discover which properties suit our mission)
PowerShell: More flexible than Ipconfig.  (Use the 'Where' clause to filter the output)
Also remember that you could also run Ipconfig itself from the PowerShell command line.

Guy's Advice

Either work through my learning progression by starting with Objective 1 (recommended), or else if you are in a hurry, cut to the chase, and head for Objective 3 PowerShell: More flexible than Ipconfig.

Pre-requisites and Checklist

Download PowerShell from Microsoft's site.  One interesting point is that there are different versions of PowerShell for XP, Windows Server 2003 and Vista.

Method 1 (Quick)

• Copy the code into memory
• Launch PowerShell
• Right-click the PowerShell symbol
• Edit --> Paste
• Press enter to execute the code
• See screenshot to the right

Method 2 (Best)

• Prepare to run cmdlets with this PowerShell command:
  set-ExecutionPolicy RemoteSigned
• Copy the code below into a text file.
• Save the file with a .ps1 extension, for example network.ps1
• In PowerShell, navigate to where you saved network.ps1
• Issue this command:
  .\network 
  (dot backslash filename)

Objective 1) - List WMI Objects

Here is a cmdlet which identifies all the Network WMI objects.

Learning Points

Note 1: Because PowerShell is so simple, yet so efficient, we need fewer commands than for a corresponding VBScript.  Indeed, the bare minimum to get started, and display all the WMI objects is these 8 letters with a dash in the middle:
gwmi -list     # gwmi is an alias for get-wmiobject

Note 2: Observe the (|) pipe.  You will use this symbol hundreds of times in PowerShell, what happens is the output of the wmiobject list is pumped into the 'where' clause, which pulls out all the entries that contain the word "network".  My thinking was get-wmiobject -list produces too many objects.

Note 3: I deliberately don't use many aliases in my scripts, but I make an exception for ft (format-Table) because it's so useful for controlling the display of PowerShell's output.  Do try the above script with, and without, the last word, 'name'.

Objective 2) - WMIObject | get-Member (Discover which properties to use in our mission)

This script identifies the properties available for the object: Win32_NetworkAdapterConfiguration.  Here below is a classic example of the get-Member construction.

Learning Points

Note 1: Observe how -class homes in on the object that we are interested in, namely:
Win32_NetworkAdapterConfiguration.

Note 2: If you wished to manipulate the TCP/IP settings, you could investigate which methods are available by substituting 'Method' for the last word, 'Property'.  Alternatively, you could omit the '-Membertype Property' phrase altogether.

Objective 3) - PowerShell: More flexible than Ipconfig

Here is the main script illustrating PowerShell's ability to display information about your TCP/IP properties.

Note 1: The properties that I have chosen are not important.  This is just an example to get you started; it would make my day if you substituted properties that you researched from Example 2: Get-Member, for example, .DefaultGateway or .IPSubnet instead of .MacAddress.

Note 2:  My old friend 'Barking' Eddie thought that my printer needed cleaning when he saw ` in my script.  Actually this character (`), found at the top left of the keyboard, is called a backtick.  What the backtick does is tell PowerShell - 'This command continues on the next line'.  Just to be clear, this character corresponds to ASCII 096, and is not a misplaced comma!

Note 3: To loop though all the network adapters, I chose the ForEach construction.  In PowerShell in general, and ForEach in particular, the type of bracket is highly significant; (ellipses for the condition) and {curly for the block command}.

Note 4:  Most of my scripts employ the 'Where' clause to filter the output.  In this case I wanted to discard data concerning any virtual network cards.

Note 5: I almost forgot, $strComputer controls which computer you are analysing.  Again, it would make my day if altered "." to the hostname of another machine on your network.

Summary of PowerShell: More flexible than Ipconfig

The aim of this script is to show you that PowerShell can not only mimic Ipconfig, but also exceed its capabilities.  In particular, I wanted to show how PowerShell could customise list of TCP/IP properties in its output.  It would also be useful to create a script which can display TCP/IP information from other machines on the network.

See Also

• Windows PowerShell Home  • Introduction  • Cmdlets  • Exchange 2007  • Profile.ps1  • $_.Pipeline

If you see an error of any kind, do let me know.  Please report any factual mistakes, grammatical errors or broken links, I will be happy to not only to correct the fault, but also to give you credit.

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