What is WOL? How to enable Wake-on-LAN

What is WOL? Have you ever thought about starting your computer without touching the power button? Do you think it's possible? It is, with Wake On LAN. This method lets you start your computer remotely without pressing Power. Let's look at Mona Media explains what WOL is and what WOL can do.

What is WOL?

WOL – Wake On LAN is a network standard widely used in computing that lets you switch on a computer remotely over the network. With WoL, a computer can be switched on from any state: hibernation, sleep or even completely off.

WOL works on different platforms including Windows, Mac and Linux. As long as the computer has Wake on LAN, you can reach it remotely for any purpose. For example, if you frequently use remote server management data access, gaming or TeamViewer, it is very useful.

WOL depends on two things: the motherboard and the network card (wired or wireless), both of which must support WOL, so you don't need any app to enable the configuration. Nearly all computers today have a network card with this feature built in. If the motherboard has no built-in support, you have to buy an extra network card to get WoL.

How WOL works on your system

WOL works by sending a Magic Packet to the location that holds the MAC address matching the network card. On every platform, magic packets are delivered with dedicated software, a website or a router.

UDP 7 and UDP 9 are the two common ports used for Wake-On-LAN magic packets. Because of how this technology works, which keeps power flowing to the network card, your computer's battery will drain faster.

WOL packets are normally sent across the whole network. They contain data such as the network broadcast address, subnet information and the MAC address of the target device's network card. This holds whether you use Wi-Fi or Ethernet.

Using this technology at home or on secure networks raises no particular concern. Many motherboard makers provide software that works with WOL for cases where it isn't configured or is secure.

How does Wake-on-LAN work?

If your computer is plugged in and connected to the internet, a Magic Packet containing the MAC address is sent to it. It is sent through dedicated equipment, a router or a website.

Put simply, Wake-On-LAN works like this: the network card detects the Magic Packet, the computer receives the signal and starts itself. So even when the computer is off (but still plugged in), the network card keeps drawing power.

Because the network card is always active, it picks up the power-on signal quickly with no interruption. When a server sends a packet across the network you are on, it carries the subnet, the network address and the MAC address (of the device you want to start).

How to enable Wake-On-LAN

How to enable Wake On LAN is probably what interests you most. Below we show you how to turn on WOL in the BIOS, Windows, macOS and Linux.

In the BIOS

On most older computers, and on many current ones, the Wake-On-LAN option is hidden in the BIOS. To enter the BIOS, press a key while the computer is starting up (usually Backspace, Esc, F12, and so on).

Once in the BIOS setup, look at the advanced options, Power Management or a similar section. On HP computers, the setting is under the profile area. On ASUS computers, Wake-On-LAN sits two levels down in the menu system.

In practice, not every computer makes the relevant option easy or obvious to find, because each BIOS is designed differently.

If you have trouble, check the user manual for your device or motherboard, or search Google. You can also download the product's PDF documentation from the manufacturer.

In Windows

To enable WOL in your operating system, follow these steps:

• Step 1: Open the Start menu and search for Device Manager.
• Step 2: When the Device Manager window opens, expand Network adapters.
• Step 3: Right-click the network card, choose Properties, then go to the Advanced tab.
• Step 4: Scroll down to find Wake on Magic Packet and set the value to Enabled. With Wake on, you can change settings for other modes as well. Note: Some devices don't show a similar option, but WOL still works reliably.
• Step 5: Go to the Power Management tab and allow the device to wake the computer. Click OK when done (allow only a Magic Packet to wake the device).

In macOS

Open System Preferences, then choose Energy Saver. An option such as Wake for network access, or something similar, will appear. Turning it on means WOL is enabled.

In Linux

On Linux, check whether your device supports Wake-On-LAN by opening a terminal and installing ethtool with this command:

sudo  apt-get  install  ethtool

Then check compatibility with this command:

sudo  ethtool  eth0

If your computer's default interface is something other than eth0, use that name in place of eth0.

Under Supports Wake-on, if the letters include g, you can use Magic Packet for WOL. Enable it with this command:

sudo  ethtool  -s  eth0  wol  g

You can run the command to see whether it is enabled. Look at the Wake-on line of the output and you will see the letter g in place of the current d.

How do you test WOL?

How do you know whether Wake-On-LAN is working? We'll show you an easy way to check.

You have plenty of options for sending a WOL request. Depicus offers a range of tools to wake a computer: a GUI-based tool for Windows, or a command-line tool that works on both macOS and Windows.

If you don't want to install any other software, use DD-WRT, which supports Wake-On-LAN. When you're away from home or the office, your Android phone can probably still start your computer remotely.

If you want to switch on your device from another desktop computer, you can use TeamViewer. You then start the device with the Wake button inside the software.

Note: depending on the program, WOL only works when you send the Magic Packet from a PC on your current network. When the program doesn't make network connections, you need to forward UDP ports 7 and 9 (for the MAC address) in your router settings.

Is WOL useful for users?

From the information above, you can see that this technology lets you start a computer from anywhere, and that is all it does. After switching the device on remotely, you need other tools to use it, such as TeamViewer or Remote Desktop (a version that supports WOL).

With this feature, you can fetch data remotely even when you leave the computer at home. Because it works directly at the hardware level, every operating system can support it. Each operating system sets it up differently, however, as we described above.

Note: Wake-On-LAN can only start a computer remotely. It does not handle security or screen passwords, and it cannot shut the device down again, which keeps the technology safer.

We hope this article has helped you understand what WOL is better, along with how to enable Wake-On-LAN successfully, so you can use WOL more flexibly in your work.