Charlie Russel's Blog

I’ve been working with Windows Server 2016 CTP5 recently, and because I installed it without the Desktop Experience (what we used to call a Server Core installation), I’m having to do everything in Windows PowerShell. No complaints, I enjoy it, but it does force me to think about things a bit sometimes.

One of the tasks I needed to do was promote a new server to be a secondary domain controller. The PowerShell command for this is: Install-ADDSDomainController. But before you start promoting a new DC, it’s a really good idea to test that the promotion will succeed by using the Test-ADDSDomainControllerInstallation cmdlet. So, I combined the two steps into a simple script that allows you to run the test, and if the output looks clean, finish the installation and initiate a reboot.

The script is smart enough to realize you haven’t installed the ActiveDirectory feature yet, and goes ahead and installs it for you.

<# 
.Synopsis 
Tests a candidate domain controller, and then promotes it to DC.

.Description 
Promote-myDC first tests if a domain controller can be successfully promoted, and, 
if the user confirms that the test was successful, completes the promotion and 
restarts the new domain controller. 

.Example 
Promote-myDC -Domain TreyResearch.net

Tests if the local server can be promoted to domain controller for the 
domain TreyResearch.net. The user is prompted after the test completes 
and must press the Y key to continue the promotion. 

.Parameter Domain 
The domain to which the server will be promoted to domain controller. 

.Inputs 
[string] 

.Notes 
    Author: Charlie Russel 
 Copyright: 2016 by Charlie Russel 
          : Permission to use is granted but attribution is appreciated 
   Initial: 05/14/2016 (cpr) 
   ModHist: 
          : 
#> 
[CmdletBinding()] 
Param( 
     [Parameter(Mandatory=$True,Position=0)] 
     [string] 
     $Domain 
     )

Write-Verbose "Testing if ADDSDeployment module is available" 
If ( ! (Get-Module ADDSDeployment )) { 
   Write-Verbose "Installing the ActiveDirectory Windows Feature, since you seem to have forgotten that." 
   Install-WindowsFeature -Name ActiveDirectory -IncludeManagementTools 
   Write-Host "" 
}

If ( ! (Get-Module ADDSDeployment )) { 
   throw "Failed to install the ActiveDirectory Windows Feature." 
}

Write-Verbose "Testing if server $env:computername can be promoted to DC in the $Domain domain" 
Write-Host "" 
Test-ADDSDomainControllerInstallation ` 
      -NoGlobalCatalog:$false ` 
      -CreateDnsDelegation:$false ` 
      -CriticalReplicationOnly:$false ` 
      -DatabasePath "C:\Windows\NTDS" ` 
      -DomainName $Domain ` 
      -LogPath "C:\Windows\NTDS" ` 
      -NoRebootOnCompletion:$false ` 
      -SiteName "Default-First-Site-Name" ` 
      -SysvolPath "C:\Windows\SYSVOL" ` 
      -InstallDns:$true ` 
      -Force 
Write-Host "" 
Write-Host "" 
Write-Host ""

Write-Host -NoNewLine "If the above looks correct, press Y to continue...  " 
$Key = [console]::ReadKey($true) 
$sKey = $key.key

Write-Verbose "The $sKey key was pressed." 
Write-Host "" 
Write-Host "" 
If ( $sKey -eq "Y" ) { 
   Write-Host "The $sKey key was pressed, so proceeding with promotion of $env:computername to domain controller." 
   Write-Host "" 
   sleep 5 
   Install-ADDSDomainController ` 
      -SkipPreChecks ` 
      -NoGlobalCatalog:$false ` 
      -CreateDnsDelegation:$false ` 
      -CriticalReplicationOnly:$false ` 
      -DatabasePath "C:\Windows\NTDS" ` 
      -DomainName $Domain ` 
      -InstallDns:$true ` 
      -LogPath "C:\Windows\NTDS" ` 
      -NoRebootOnCompletion:$false ` 
      -SiteName "Default-First-Site-Name" ` 
      -SysvolPath "C:\Windows\SYSVOL" ` 
      -Force:$true 
} else { 
   Write-Host "The $sKey key was pressed, exiting to allow you to fix the problem." 
   Write-Host "" 
   Write-Host "" 
}