I wanted to blog this quick bit of PowerShell as I could not find it anywhere else on the web whilst searching.

I needed to check the connected domain on a machine to see if SSL was configured and enabled for LDAP, the following script checks to see if SSL is enabled on one of the domain controllers in the current domain and then tries to make a connection to see if it works.

This can of course be altered to list and check all domain controllers easy enough:

$dc = [System.DirectoryServices.ActiveDirectory.Domain]::getCurrentDomain().DomainControllers | Select -First 1
$LDAPS = [ADSI]"LDAP://$($dc.name):636"
try {
	$Connection = [adsi]($LDAPS)
} Catch {
}
If ($Connection.Path) {
	Write-Host "Active Directory server correctly configured for SSL, test connection to $($LDAPS.Path) completed."
} Else {
	Write-Host "Active Directory server not configured for SSL, test connection to LDAP://$($dc.name):636 did not work."
}

Recently I needed to perform some actions in PowerCLI from the ESXi Shell, as you may know there are currently no cmdlets from VMware to allow you to run shell commands but one option which is popular within the communities is using a 3rd party tool called plink.exe to run the commands via SSH.

Examples of this can be seen here and here.

Download plink.exe via PowerShell

The script I was writing was for someone who I knew didn’t already have plink installed and I wanted them to have little to no effort when using this script so the first trick I wanted to share was the ability to check for plink.exe and download it if it wasn’t in the same directory as the script, this can be seen below:

$myDir = Split-Path -Parent $MyInvocation.MyCommand.Path
$PlinkLocation = $myDir + "\Plink.exe"
If (-not (Test-Path $PlinkLocation)){
	Write-Host "Plink.exe not found, trying to download..."
	$WC = new-object net.webclient
	$WC.DownloadFile("http://the.earth.li/~sgtatham/putty/latest/x86/plink.exe",$PlinkLocation)
	If (-not (Test-Path $PlinkLocation)){
		Write-Host "Unable to download plink.exe, please download from the following URL and add it to the same folder as this script: http://the.earth.li/~sgtatham/putty/latest/x86/plink.exe"
		Exit
	} Else {
		$PlinkEXE = Get-ChildItem $PlinkLocation
		If ($PlinkEXE.Length -gt 0) {
			Write-Host "Plink.exe downloaded, continuing script"
		} Else {
			Write-Host "Unable to download plink.exe, please download from the following URL and add it to the same folder as this script: http://the.earth.li/~sgtatham/putty/latest/x86/plink.exe"
			Exit
		}
	}	
}

Accept plink.exe host key automatically

Secondly when connecting to a host for the first time you will need to accept the host key and allow plink.exe to connect to the host, the message is similar to the one below:

At the moment there is no option in plink.exe to skip the host key checking, however after some searching and messing around I came upon a solution.

It turns out you can actually send a Y to the script you are running by simply piping “echo Y” to plink.exe, this sends a Y accepting the host key when the question is asked from the command line, this can be scripted like the below example:

Echo Y | Plink.exe…..

Hopefully someone will find these useful in the future as I did with this script.