Wake on Lan

Sending a magic packet using PowerShell

The WOL magic packet is a byte array with 6 bytes of value 255 and then 16 repetitions of the MAC address.

$mac = '01-23-45-67-89-AB';
[System.Net.NetworkInformation.NetworkInterface]::GetAllNetworkInterfaces() | Where-Object { $_.NetworkInterfaceType -ne [System.Net.NetworkInformation.NetworkInterfaceType]::Loopback -and $_.OperationalStatus -eq [System.Net.NetworkInformation.OperationalStatus]::Up } | ForEach-Object {
    $networkInterface = $_
    $localIpAddress = ($networkInterface.GetIPProperties().UnicastAddresses | Where-Object { $_.Address.AddressFamily -eq [System.Net.Sockets.AddressFamily]::InterNetwork })[0].Address
    $targetPhysicalAddress = [System.Net.NetworkInformation.PhysicalAddress]::Parse(($mac.ToUpper() -replace '[^0-9A-F]',''))
    $targetPhysicalAddressBytes = $targetPhysicalAddress.GetAddressBytes()
    $packet = [byte[]](,0xFF * 102)
    6..101 | Foreach-Object { $packet[$_] = $targetPhysicalAddressBytes[($_ % 6)] }
    $localEndpoint = [System.Net.IPEndPoint]::new($localIpAddress, 0)
    $targetEndpoint = [System.Net.IPEndPoint]::new([System.Net.IPAddress]::Broadcast, 9)
    $client = [System.Net.Sockets.UdpClient]::new($localEndpoint)
    try { $client.Send($packet, $packet.Length, $targetEndpoint) | Out-Null } finally { $client.Dispose() }
}

Code originally found at this StackOverflow answer.

More details - https://www.pdq.com/blog/wake-on-lan-wol-magic-packet-powershell/