Get Active Directory Forest Domain Controllers

Like the other script posted today, this was written to help out the networking team with a simple inventory of DCs in a large Active Directory forest.  It queries all domains in the forest, creating a CSV file with the Domain, DC name, IP Address, OS, AD Site and Roles.  It can optionally ping the DCs to see whether they are online. Some code notes:

• Line 9 uses [environment]::GetFolderPath(‘Desktop’) instead of the more familiar $env:userprofile\Desktop. Unlike the $Env drive, this method works when there is GPO based desktop re-direction.
• Lines 17-20 demonstrate that for a menu list of multiple lines you can simply uses quotes at the beginning and end
• Lines 29 through 54 are wrapped as an array, beginning with “@(” and ending with “)”. This is a simple workaround to allow you to pipe the entire results to Export-csv
• If you uncomment line 65, you will see how using invoke-item will open the log file in Excel or other program associated with .CSV files.

<#
Get-ForestDClist.ps1
Alan Kaplan 1/24/20
Get list of DCs in Forest, with optional ping
Does not rely on AD module or admin rights
#>

#Default logfile
$desktop = [environment]::GetFolderPath('Desktop')
$logfile = "$Desktop\DCs_" + $(Get-Date).ToString("yyyyMMdd_HHmm") + '.csv'

$Forest = ([System.DirectoryServices.ActiveDirectory.Forest]::GetCurrentForest())
$RootDom = ($Forest).RootDomain
$dList = ($Forest.Domains).Name | Sort-Object   -CaseSensitive

Add-Type -assemblyname Microsoft.visualBasic
$msg = "This will get a list of all DCs in $RootDom.
1) Get list with online state (ping)
2) Get list without online state (no ping)
0) Exit"
$retval = [Microsoft.VisualBasic.Interaction]::InputBox($msg, "Create List of All DCs in Forest", 0)
switch ($retval) {
    1 { $bPing = $true }
    2 { $bPing = $false }
    Default { Exit }
}

Write-Host "Getting all DCs in $rootDom ..."
@(foreach ($dom in $dlist) {
        $DomainContext = new-object System.directoryServices.ActiveDirectory.DirectoryContext("Domain", $Dom)
        $ADSIDomain = [System.DirectoryServices.ActiveDirectory.Domain]::GetDomain($DomainContext)
        $ADSIDomain.DomainControllers |
        ForEach-Object {
            $msg = "Getting all DCs in $dom"
            if ($bPing) { $msg = "$msg with online state" } 
            Write-Progress -activity $msg -status ($_).Name      
        
            if ($bPing) {
                $bOnline = Test-Connection $_.IPAddress -count 1 -Quiet -ea SilentlyContinue
            }
            Else {
                $bOnline = "Not Tested"
            }
            [PSCustomObject]@{
                Domain       = $domc
                Name         = $_.Name
                'IP Address' = $_.IPAddress
                Online       = $bOnline
                OS           = $_.OSVersion
                'AD Site'    = $_.SiteName
                'AD Roles'   = ($_.Roles -join ", ").toUpper() -replace 'Role', ''
            }
        } 
    }) | Sort-Object Domain, Name |
Export-csv $logfile -NoTypeInformation

Write-Progress "Done" -completed
Clear-Host
Write-host "Done. Report is $logfile"
#Open report when done
#invoke-item $logfile