### Test-NetConnection function ```powershell Test-NetConnection -Port 445 <IP> Test-NetConnection -Port 25 <IP> ``` ### Scan the first 1024 ports on the DC with Powershell one-liner 엄청 느림 ```powershell 1..1024 | % {echo ((New-Object Net.Sockets.TcpClient).Connect("<IP>", $_)) "TCP port $_ is open"} 2>$null ``` ### 빠른 버전 ```powershell 1..1024 | % { $port = $_ $client = New-Object System.Net.Sockets.TcpClient $connectTask = $client.ConnectAsync("<IP>", $port) if ($connectTask.Wait(200)) { # 200ms timeout Write-Output "TCP port $port is open" $client.Close() } } ```