PowerShell DHCP Scope in Windows Server 2012

PowerShell v3 Add-DhcpServerv4Scope

In Windows Server 2012 you can employ PowerShell to configure DHCP.  While there are dozens of PowerShell DHCP functions (cmdlets), on this page I concentrate on the aptly named DhcpServerv4Scope.

• Create a DHCP Scope with PowerShell
• Research PowerShell DHCP Functions (Cmdlets)
• Edit Your DHCP Scope with Set-DhcpServerv4Scope
• Remove a DHCP Scope with PowerShell

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Basics of Creating a DHCP Scope

When you assign IPv4 and IPv6 addresses via a DHCP server the key concept is the scope.  The minimum four properties to specify are: a name for the scope, the starting and ending IP address of the range, and the subnet mask.  For the sake of getting started I will gloss over the numerous optional properties.

How to Create a DHCP Scope with PowerShell

Note 1: I needed PowerShell's backtick (`) because I wanted to show each parameter (property) on its own line.

Check your new scope
I recommend that you compare:

a) The results of PowerShell's:

Get-DHCPServerv4Scope

with

b) What you see in the DHCP Server's GUI, see screenshot above right.

Windows Server 12 DHCP Server's GUI

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Researching PowerShell DHCP Functions (Cmdlets)

I want to concentrate on the DHCPServerV4 commands, note that 'V', and be aware of the parallel IP V6 commands.

Resulting Functions (Cmdlets):

It's taking a while to get used to the concept that Add-DhcpServerv4Scope, and similar Windows Server 12 PowerShell commands, are not actually cmdlets, but functions.

Challenge 1: Repeat, but substitute 'Get' for 'Add'.

Challenge 2: Go the whole nine yards, substitute '*' for 'Add'.

Edit Your DHCP Scope with Set-DhcpServerv4Scope

Configuring DHCP through PowerShell looks easy; after all there are dozens of cmdlets, or to give them their proper term -functions.  However, the secret of success is to pay close attention to the ScopeId property.  In this example its value is precisely: 192.168.1.0

Note 2:  -ScopeId took me ages to figure out.  My problem was overthink, no need for any brackets or speech marks, just the plain IP address.  Remember that zero at the end and forget about appending the name of the scope.

Note 3: The syntax of -LeaseDuration, or -Lease if you prefer, cause me a few headaches.  Just study my timespan example and amend Days 9 as needed.

Research DHCP Properties or Parameters

Let us assume that you need to add information to the DHCP scope, for example, to set a description, or to change the 'State' from inactive to active.  To research parameter I recommend that you prefix the PowerShell DHCP function with Get-Help.

Note 4: This reveals new parameters such as -State and -Description.  It also reminds us of old friends such as -LeaseDuration and -EndRange.

Note 5: You see pretty much the same parameters if substitute the verbs, Get or Remove for Set.

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Remove a DHCP Scope with PowerShell

My use for this technique was in testing.  In truth I got in a right old stew before I discovered the simple and elegant:

Note 6: For consistency PowerShell always uses the Remove verb, and never delete or kill.

Out-takes

The following shows the thought processes of a demented PowerShell scripter.

Note 7: This example proved to me that the value of the ScopeId was a pure dot decimal number 192.168.1.0, and not [192.168.1.0 Guy] or other even more bizarre ideas.

See how PowerShell can add features to Windows Server 2012 »

Summary of Add-DhcpServerv4Scope in Windows Server 2012

How PowerShell's DHCP scope functions (cmdlets) can configure Windows Server 2012. Examples of Add and Set-DhcpServerv4Scope explain how to create the scope's range and set the lease.

Microsoft Windows Server 2012 Topics

• Windows Server 2012 Home   • Install Windows Server 2012   • Windows Server 2012 PowerShell

• PowerShell Add-WindowsFeature   • Windows Server 2012 Hyper-V  • Disable IE ESC Server 2012

• Shutdown Windows Server 2012   • PowerShell DHCP Scope   • Network Performance Monitor