TrackRIDPools.ps1

if(-not (Get-CimInstance -ClassName Win32_ComputerSystem -Property DomainRole).DomainRole -band 4){
    # Computer's not a DC
    return
}

$logProperties = @{
    LogName = 'System'
    Source  = 'RIDPoolTracker'
}
if (-not(Get-Eventlog -List | Where-Object {$_.LogDisplayName -eq $logProperties.LogName})) {
    New-EventLog @logProperties
}

# execute the ridmanager diagnostic locally
$rIDTest = @( dcdiag.exe /test:ridmanager /v )

# grab the RID allocation pool range from the output
if($rIDTest -cmatch 'rIDAllocationPool is (\d+ to \d+)'){
    # log new range to the event log 
    $message = $Matches[1]
    Write-EventLog "New rIDAllocationPool: $message" -EventId 100 @logProperties
}