Dynamic Variable Values

Once again, my good friend from Texas asked me for a little PowerShell assistance. Being an old Cold Fusion junkie, he sent me his cryptic CF code:

Disclaimer (Blogger hates Angle Brackets)
cfset variable1="blah"
cfset var2="yada"

This statement would've then returned the value of "#blahyada#"
cfoutput #Evaluate("#variable1#")var2# cfoutput

It is basically a self-renaming variable based on the value of another variable - no idea if PowerShell can do that.

After my brief Cold Fusion viewing induced nausea subsided, I decided to help him. This is the sample I sent him:
$DallasAddress = "123 Cowboy Ave."
$ColumbusAddress = "456 Hayes St."
$ClevelandAddress = "910 Kosar Blvd."

$loc = "Dallas"
# Returns "123 Cowboy Ave."
(Get-Variable ($loc+"Address")).value

He is now happy and has learned a little bit more PowerShell. As for me, he has added yet another 6 bottles of my favorite beverage to the till.
Enjoy!

Query DNS with PowerShell

Following is a script that will enable you to query DNS for duplicate records. Be sure to change the location of the output file!

# Using WMI, retrieve all the duplicate DNS records
$DNS = Get-WmiObject -ComputerName 'DNS-Server' `
   -Namespace 'root\MicrosoftDNS' `
   -Class MicrosoftDNS_AType `
   -Filter "ContainerName='Your Container'" | `
Group-Object OwnerName | Where-Object {$_.Count -gt 1}

# Create our CSV file to hold the data
$file = 'c:\temp\DNS.csv'
New-Item -ItemType file -Path $file -Force 
Add-Content -Path $file -Value "Name,IPAddress"

# Iterate of the DNS items grabbing the name and IPAddress
foreach ($item in $DNS) {
    foreach ($IPAddresses in $item.Group) {
        $value = "{0},{1}" -f $item.name,$IPAddresses.IPAddress
        Add-Content -Path $file -Value $value
    }
}

Results should look something like:

Name	IPAddress
Server1	10.194.111.22
Server2	10.140.111.22
ServerA	10.333.19.121
ServerB	10.333.131.24

Enjoy!

Calling a Web Service with PowerShell

I often need to be notified of a certain condition when a scheduled script executes.
With PowerShell V2, I can take advantage of our internal paging web service by using the New-WebServiceProxy cmdlet to take care of this notification.

Check out the help on this cmdlet to see a full list of capabilities. Help New-WebServiceProxy -Full

Before we dive into the actual call, lets interrogate the web service to see what it can do.
# Create a proxy for the Paging web service
$page = New-WebServiceProxy -Uri 'http://InternalPagingService/pageservice.asmx'

#List the methods
$page Get-Member -MemberType Method
You should see something like this:

The method we are going to use is RequestSinglePage.

Enter the following to see the expected parameters:
($page Get-Member -Name RequestSinglePage).definition

Looking at the end of the definition we see 2 parameters:
- string PagerId
- string NumericOrAlphaMessage

We now have all we need to page from script!
$page.RequestSinglePage('3141','Testing Page Web Service from PowerShell')

If you need confirmation of the Web Service call, you can look at the FunctionStatus property of the executed Web Service.
($page.RequestSinglePage('3141','Test Page from PowerShell')).FunctionStatus

This returns - SUCCESS

Wrapping this web service call around some return code if fairly straight forward and is left as an exercise for the reader.

If you don't have an internal Web Service handy, try out http://www.webservicex.net/WeatherForecast.asmx

Enjoy!