What is Wake-On-LAN ?Wake-on-LAN (WoL) is an Ethernet or token ring computer networking standard that turns on a system or awaken it by a network message. Thus the user does not need to be physically present. It enables you to access your files or folders remotely, even if the computer will be low-power state to save electricity.
Requirements for Wake-On-LAN:
Wake-On-LAN needs two things to work: your motherboard and your network card.
- The motherboard should be connected to an ATX-compatible power supply
- A peer to peer network between two or more computers.
- The Ethernet card must support the functionality.
- The computer must be in either Sleep or Hibernation mode for this to work.
The Magic Packet: Working Mechanism for Wake-On-LAN
With the help of a specially designed frame called magic packet, Wake-on-LAN or WOL works. Magic Packet is a byte array with 6 bytes of the value of all 255 (FF FF FF FF FF FF in hexadecimal), followed by sixteen repetitions of the target computer’s 48-bit MAC address, for a total of 102 bytes. In simple words, it is a standard wake-up frame that aims a specific network interface. There are some basic limitations of a magic packet:
- It requires the target computer’s MAC address
- It does not provide us with a delivery confirmation
- The target computer must have the hardware support of Wake-On-LAN.
Enable The Wake-On-LAN On Your SystemIn order to enable Wake-On-LAN on your system, you need to alter the settings under your BIOS and on your computer.
- To reach bios settings, you need to press a key as you boot the computer. The key would be shown on the screen when it comes up. Usually, it is F2, Escape or Delete.
- Once you are under BIOS settings, check under Power Management or Advanced Options.
- You need to enable settings related to Power Up on PCI card, LAN, or Network.
- Click Save to keep the changes and exit the BIOS settings.
Windows OS Settings:
- Go to Start Menu and type Device Manager.
- In Device Manager panel, expand Network Adapter.
- Right click on the network card and go to Properties, then click on the Advanced tab.
- On the Advanced tab, under the property, scroll down. In “Wake on Magic Packet”, change the value to “Enabled.”
- Switch to Power Management and check mark the boxes beside “Allow this device to wake the computer” and “Only allow a magic packet to wake the computer”
- Click OK.
In Mac OS
- Locate Apple icon from the top left side corner and click on it.
- Now choose System Preferences -> Energy Saver Preferences.
- In Energy Saver Preferences pane, you will get an option similar to, “Wake for Network Access”
- Open terminal and install ethtool with the following command: sudo apt-get install ethtool
- To check compatibility, run this command: sudo ethtool eth0
- If the default interface is something else, substitute it for eth0.
- Now find the “Supports Wake-on” section. If the letter beside is g, you can use magic packets for Wake-on-LAN. To enable this option, you have to execute the below mentioned command: sudo ethtool -s eth0 wol g
- Check the “Wake on” section to enable the feature. The letter would be g instead of d.