Performing Networking Tasks

Because TCP/IP is the most commonly used network protocol, most low-level network protocol administration tasks involve TCP/IP. In this section, we use Windows PowerShell and WMI to do these tasks.

Listing IP Addresses for a Computer

To get all IP addresses in use on the local computer, use the following command:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=TRUE -ComputerName . | Format-Table -Property IPAddress

The output of this command differs from most property lists, because values are enclosed in braces:


{} {} {} {}

To understand why the braces appear, use the Get-Member cmdlet to examine the IPAddress property:

PS> Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=TRUE -ComputerName . | Get-Member -Name IPAddress
TypeName: System.Management.ManagementObject#root\cimv2\Win32_NetworkAdapter
Name      MemberType Definition
----      ---------- ----------
IPAddress Property   System.String[] IPAddress {get;}

The IPAddress property for each network adapter is actually an array. The braces in the definition indicate that IPAddress is not a System.String value, but an array of System.String values.

Listing IP Configuration Data

To display detailed IP configuration data for each network adapter, use the following command:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=TRUE -ComputerName .

The default display for the network adapter configuration object is a very reduced set of the available information. For in-depth inspection and troubleshooting, use Select-Object or a formatting cmdlet, such as Format-List, to specify the properties to be displayed.

If you are not interested in IPX or WINS properties—probably the case in a modern TCP/IP network—you can use the ExcludeProperty parameter of Select-Object to hide properties with names that begin with "WINS" or "IPX:"

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=TRUE -ComputerName . | Select-Object -Property [a-z]* -ExcludeProperty IPX*,WINS*

This command returns detailed information about DHCP, DNS, routing, and other minor IP configuration properties.

Pinging Computers

You can perform a simple ping against a computer using by Win32_PingStatus. The following command performs the ping, but returns lengthy output:

Get-WmiObject -Class Win32_PingStatus -Filter "Address=''" -ComputerName .

A more useful form for summary information a display of the Address, ResponseTime, and StatusCode properties, as generated by the following command. The Autosize parameter of Format-Table resizes the table columns so that they display properly in Windows PowerShell.

PS> Get-WmiObject -Class Win32_PingStatus -Filter "Address=''" -ComputerName . | Format-Table -Property Address,ResponseTime,StatusCode -Autosize

Address   ResponseTime StatusCode
-------   ------------ ----------            0          0
A status code of 0 indicates a successful ping.

You can use an array to ping multiple computers with a single command. Because there is more than one address, use the ForEach-Object to ping each address separately:

"","localhost","" | ForEach-Object -Process {Get-WmiObject -Class Win32_PingStatus -Filter ("Address='" + $_ + "'") -ComputerName .} | Select-Object -Property Address,ResponseTime,StatusCode

You can use the same command format to ping all of the computers on a subnet, such as a private network that uses network number and a standard Class C subnet mask (, Only addresses in the range of through are legitimate local addresses (0 is always reserved for the network number and 255 is a subnet broadcast address).

To represent an array of the numbers from 1 through 254 in Windows PowerShell, use the statement 1..254. A complete subnet ping can be performed by generating the array and then adding the values onto a partial address in the ping statement:

1..254| ForEach-Object -Process {Get-WmiObject -Class Win32_PingStatus -Filter ("Address='192.168.1." + $_ + "'") -ComputerName .} | Select-Object -Property Address,ResponseTime,StatusCode

Note that this technique for generating a range of addresses can be used elsewhere as well. You can generate a complete set of addresses in this way:

$ips = 1..254 | ForEach-Object -Process {"192.168.1." + $_}

Retrieving Network Adapter Properties

Earlier in this user's guide, we mentioned that you could retrieve general configuration properties by using Win32_NetworkAdapterConfiguration. Although not strictly TCP/IP information, network adapter information such as MAC addresses and adapter types can be useful for understanding what is going on with a computer. To get a summary of this information, use the following command:

Get-WmiObject -Class Win32_NetworkAdapter -ComputerName .

Assigning the DNS Domain for a Network Adapter

To assign the DNS domain for automatic name resolution, use the Win32_NetworkAdapterConfiguration SetDNSDomain method. Because you assign the DNS domain for each network adapter configuration independently, you need to use a ForEach-Object statement to assign the domain to each adapter:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=true -ComputerName . | ForEach-Object -Process { $_. SetDNSDomain("") }

The filtering statement "IPEnabled=true" is necessary, because even on a network that uses only TCP/IP, several of the network adapter configurations on a computer are not true TCP/IP adapters; they are general software elements supporting RAS, PPTP, QoS, and other services for all adapters and thus do not have an address of their own.

You can filter the command by using the Where-Object cmdlet, instead of using the Get-WmiObject filter.

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -ComputerName . | Where-Object -FilterScript {$_.IPEnabled} | ForEach-Object -Process {$_.SetDNSDomain("")}

Performing DHCP Configuration Tasks

Modifying DHCP details involves working with a set of network adapters, just as the DNS configuration does. There are several distinct actions you can perform by using WMI, and we will step through a few of the common ones.

Determining DHCP-Enabled Adapters

To find the DHCP-enabled adapters on a computer, use the following command:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "DHCPEnabled=true" -ComputerName .

To exclude adapters with IP configuration problems, you can retrieve only IP-enabled adapters:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "IPEnabled=true and DHCPEnabled=true" -ComputerName .

Retrieving DHCP Properties

Because DHCP-related properties for an adapter generally begin with "DHCP," you can use the Property parameter of Format-Table to display only those properties:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "DHCPEnabled=true" -ComputerName . | Format-Table -Property DHCP*

Enabling DHCP on Each Adapter

To enable DHCP on all adapters, use the following command:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=true -ComputerName . | ForEach-Object -Process {$_.EnableDHCP()}

You can use the Filter statement "IPEnabled=true and DHCPEnabled=false" to avoid enabling DHCP where it is already enabled, but omitting this step will not cause errors.

Releasing and Renewing DHCP Leases on Specific Adapters

The Win32_NetworkAdapterConfiguration class has ReleaseDHCPLease and RenewDHCPLease methods. Both are used in the same way. In general, use these methods if you only need to release or renew addresses for an adapter on a specific subnet. The easiest way to filter adapters on a subnet is to choose only the adapter configurations that use the gateway for that subnet. For example, the following command releases all DHCP leases on adapters on the local computer that are obtaining DHCP leases from

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "IPEnabled=true and DHCPEnabled=true" -ComputerName . | Where-Object -FilterScript {$_.DHCPServer -contains ""} | ForEach-Object -Process {$_.ReleaseDHCPLease()}

The only change for renewing a DHCP lease is to use the RenewDHCPLease method instead of the ReleaseDHCPLease method:

Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "IPEnabled=true and DHCPEnabled=true" -ComputerName . | Where-Object -FilterScript {$_.DHCPServer -contains ""} | ForEach-Object -Process {$_.ReleaseDHCPLease()}

When using these methods on a remote computer, be aware that you can lose access to the remote system if you are connected to it through the adapter with the released or renewed lease.

Releasing and Renewing DHCP Leases on All Adapters

You can perform global DHCP address releases or renewals on all adapters by using the Win32_NetworkAdapterConfiguration methods, ReleaseDHCPLeaseAll and RenewDHCPLeaseAll. However, the command must apply to the WMI class, rather than a particular adapter, because releasing and renewing leases globally is performed on the class, not on a specific adapter.

You can get a reference to a WMI class, instead of class instances, by listing all WMI classes and then selecting only the desired class by name. For example, the following command returns the Win32_NetworkAdapterConfiguration class:

Get-WmiObject -List | Where-Object -FilterScript {$_.Name -eq "Win32_NetworkAdapterConfiguration"}

You can treat the entire command as the class and then invoke the ReleaseDHCPAdapterLease method on it. In the following command, the parentheses surrounding the Get-WmiObject and Where-Object pipeline elements direct Windows PowerShell to evaluate them first:

( Get-WmiObject -List | Where-Object -FilterScript {$_.Name -eq "Win32_NetworkAdapterConfiguration"} ).ReleaseDHCPLeaseAll()

You can use the same command format to invoke the RenewDHCPLeaseAll method:

( Get-WmiObject -List | Where-Object -FilterScript {$_.Name -eq "Win32_NetworkAdapterConfiguration"} ).RenewDHCPLeaseAll()

Creating a Network Share

To create a network share, use the Win32_Share Create method:

(Get-WmiObject -List -ComputerName . | Where-Object -FilterScript {$_.Name -eq "Win32_Share"}).Create("C:\temp","TempShare",0,25,"test share of the temp folder")

You can also create the share by using net share in Windows PowerShell:

net share tempshare=c:\temp /users:25 /remark:"test share of the temp folder"

Removing a Network Share

You can remove a network share with Win32_Share, but the process is slightly different from creating a share, because you need to retrieve the specific share to be removed, rather than the Win32_Share class. The following statement deletes the share "TempShare":

(Get-WmiObject -Class Win32_Share -ComputerName . -Filter "Name='TempShare'").Delete()

Net share works as well:

PS> net share tempshare /delete
tempshare was deleted successfully.

Connecting a Windows Accessible Network Drive

The New-PSDrive cmdlets creates a Windows PowerShell drive, but drives created this way are available only to Windows PowerShell. To create a new networked drive, you can use the WScript.Network COM object. The following command maps the share \\FPS01\users to local drive B:

(New-Object -ComObject WScript.Network).MapNetworkDrive("B:", "\\FPS01\users")

The net use command works as well:

net use B: \\FPS01\users

Drives mapped with either WScript.Network or net use are immediately available to Windows PowerShell.