Wake On Lan (WOL)

Most of you will have heard of Wake On LAN (WOL) and maybe have even had a go with it yourself, but for those who haven't WOL is a service that lets you remotely turn on computers connected to a wired network. This is achieved by sending a "Magic Packet" to the computer's network card which then signals for the computer to wake/switch on. 

Using WOL is very simple, first of all you need to set up your client (the computer being woken) to always have it's Ethernet adapter switched on, be it an internal one or a PCI(-E) type device. This is usually achievable by simply entering the bios at start up and enabling Wake On Lan in the settings (refer to your specific motherboard/bios/computer instructions for where exactly this will be). 

Note: Some older computers and some laptops do not have the ability to WOL

Once your Ethernet adapter is set to stay on once the computer has been powered down your best bet is to double check it has worked; to do this ensure you have an Ethernet cable connected to your computer which is in turn connected to a powered up router. Then switch off your computer and the 2 lights (usually green and orange) should still be flashing. If these are not, your settings may not be saved properly, or there may be other settings in the bios preventing the Ethernet adapter receiving power. To remedy this I suggest you do a simple Google search to see if anyone else has resolved the same issue with your motherboard.

Orange light on - WOL is ready to go!

Now, the tricky bit is over believe it or not. A suitable client for sending the magic packets needs to be sourced for the device that will be doing the waking. For Ubuntu users I strongly suggest an application called "gWakeOnLan" which can be found in the USC. For a windows machine I suggest Solarwinds.net's Wake On LAN as I found it easiest to set up and it actually worked, unlike many Windows tools I have come across. For Android I suggest a tool called, once again "Wake On Lan" (the icon is a small PCI network card). IOS users should use "RemoteBoot". 

Wake On Lan - Android app

The next step is to give the software the details it needs to send it's magic packet to the correct computer. Here you will need the computer's MAC address that you want to wake along with the host name/IP address. The computer's MAC address is found in different ways on each operating system so I would once again suggest a Google search for your operating system. The host name/IP address is usually "255.255.255.255" if you are waking on a local network rather than from outside the home. If you are not waking from a Local network then you will need to find out your own personal Host name/IP address using one of the many online tutorials. The port should be 9 if you are not using a different one for your own reasons.

Once you are sure that all the details are entered correctly you can press the wake button on the software you have chosen to use. Here, if everything has gone well, your computer should begin to turn on as if you had just pressed the power button. 

Troubleshooting: 

• If the lights on the back of your computer are not flashing ensure that the computer has not had a hard shut down, where the power button has been held down to switch off the computer. For the Ethernet adapter to keep receiving power the computer needs to be shut down properly, i.e using the start menu
• Ensure that the MAC address is correct - there are no spaces at all, even between the colons.
• Be sure that the device from which you are doing the waking is securely connected to the same network/router that the device you are trying to wake is. This is especially important when using a mobile phone to wake as it might have dropped into it's mobile data connection.

If I have missed some troubleshooting let me know as I can't think of every issue that could come about!

Some uses of WOL

• Remotely switching on a home server for when it's needed
• Remotely booting your computer when you enter the house so that it is ready for use when you are!
• Basically switching any computer on that is too far away for you to be bothered reaching or is in an inaccessible place.  
• Any other imaginative ways you can dream up!

Let me know of any new ideas you come up with in the comments below!