Wake-on-LAN (WoL): An effective solution for unrestrained remoting
Being able to switch on your computer from any distance is a convenience that also simplifies everyday business. Wake-on-LAN, a long-established technology, makes remote access particularly easy.
Wake-on-LAN (WoL) is a way to remotely reactivate a computer from a low-power mode. It is an industry standard protocol from the 1990s. What makes it special is that the WoL does not require a LAN connection.
Since this standard enables remote access, everyday tasks can be performed without further ado: Accessing data and programs as well as running applications works smoothly. At the same time, companies benefit from a high degree of cost-effectiveness. After all, the computer is in energy-saving mode during this time. Programs such as TeamViewer or VNC are just as accessible as game server or file server programs. This makes file transfer within the company much easier. For private use, on the other hand, data can be transferred to mobile devices while the PC remains at home.
Whether it is possible to use Wake-on-LAN depends on the motherboard and the network card. An ATX-compatible power supply ensures that the function works. This component has already been installed in most end devices for over 10 years. However, the Ethernet or wireless card must also support the functionality. The basis for this is the BIOS or a specific firmware for the network card. Additional software, on the other hand, is not necessary.
Good to know: Although Wake-on-LAN offers a high degree of flexibility and convenience, starting the computer remotely is not always desirable. In this case it is useful to shutdown Wake-on-LAN to prevent the network command from being received via Magic Packets.
Wake-on-LAN, also known as WoL, describes a standardized procedure from the 1990s. With this standard it is possible to address computers via certain network data packets. What is special about this is that these remote devices can be in sleep mode or switched off. Thanks to so-called magic packets, it is still possible to start the computer.
To make Wake-on-LAN technology work, various components must be WoL-compatible. These include the network card, the BIOS, the operating system and the computer itself. It is then necessary to configure them accordingly. If the required compatibility is ensured and the function is activated, the Magic Packets can start the computer remotely.
Originally, the network command was aimed only at the cable-based network connection. This is different today, as more and more users are focusing on wireless technology. Therefore, solutions and special WiFi network cards that follow the same concept can now be found. Therefore, it is possible to use Wake on Lan with WiFi just like with a classic cable-based connection. The correct term for this is Wake on WLAN or WoWLAN. Both concepts use the same basic principle of Magic Packets.
How does Wake-on-Lan software work?
If the PC is compatible with WoL functionality, it basically waits for the arrival of so-called “Magic Packets”. These magic packets contain the MAC address of the network card and address the remote computer directly. Additionally, it is possible for routers or Internet-based websites to send the Magic Packets. Typically, the UDP7 and 9 parts are used for this purpose.
Although the computer appears inactive, the network card must be continuously powered to receive the packets. Therefore a higher power consumption than with a switched off PC is to be expected. The following information is contained in the Magic Packets that are normally sent across the network:
- Subnet information
- Network broadcast address
- MAC address of the network card of the target computer
- The information whether Ethernet or a wireless connection is used.
When using WoL, it is always important to address the issue of security. Within a secure network or in home use, the potential risks are limited. However, in an enterprise context, additional security mechanisms should be implemented to protect the network.
In order to be able to work with Wake on LAN, in most cases prior activation is required. How exactly the enabling works depends on the system. While enabling this functionality is particularly easy for macOS, it is much more difficult for Linux. Windows also requires a few steps before Wake-on-LAN can be used.
Although only a few clicks are necessary to activate Wake-on-LAN, the activation can be a problem for users. Although special software solutions are by no means required for activation, they make the whole process much easier. One example is Home Assistant for Wake-on-LAN. Using this solution, the activation can be realized with just one click. Direct intervention in the BIOS or the system settings is not necessary.
Activate WoL in BIOS
On many PCs, the settings for Wake-up-on-LAN are located in the BIOS. To access this environment, it is necessary to press a special key during the booting process. Usually this is Delete, Escape or F2. However, there are some exceptions, which is why the boot screen displays the exact instructions again.
In the BIOS, the WoL settings are usually located in the power management or advanced options. However, the exact location depends on the computer manufacturer. Therefore, the activation can be very different using an ASUS from using a HP computer, for example. The large differences between the individual BIOS menu systems occasionally make it a challenge to activate Wake-on-LAN.
Enable WoL in Windows
To enable Wake-on-LAN in Windows, the option must first be enabled in the BIOS. Then, the setup is done via the “Device Manager“. Here you will find a section called “Network adapters“. By right-clicking on the network adapter, it is possible to open the properties and the “Advanced” tab contained there.
Under the letter “W” there is an entry: “Wake on Magic Packet”. As soon as this value is set to “Enabled”, Wake-on-LAN is available. The other settings for “Wake on” are independent of this functionality and therefore do not need to be edited.
To check whether WoL is actually active, it is sufficient to look at the “Power Management” tab. There you will find a checkbox with the label “Allow this device to wake up the computer”. In addition, “Only one magic package to wake up the computer” should be enabled. If this is the case, the desired functionality is available.
Enable Wake-on-LAN for MacOS
To use Wake-on-LAN on a Mac, the function must also be enabled. The easiest way to do this is to open the system preferences and click on the battery. Here, there should be a checkbox with the label “Wake for Network Access” directly. If the box is not active, one click is enough to activate the function.
Enable WoL for Linux
Under Linux, for example under Ubuntu, it is also possible to provide Wake-on-LAN. At the same time, Ubuntu provides a tool that can be used to test the computer’s compatibility. The software tool is installed using the “sudo apt-get install ethtool” command via the terminal. Afterwards, it is possible to check the Wake-on-LAN compatibility via the Powershell. The command “sudo ethtool eth0” provides information about this.
The result is a listing in which a section “supports Wake-on” can be found. If the letter “g” is listed here, it means that the functionality is available. To use Wake-on-LAN, Wake-on-LAN for Linux is enabled as follows: “sudo ethtool -s eth0 wol g”.
How to succeed using WoL: With TeamViewer’s Wake-on-Lan feature
Wake on Lan makes it possible to turn on computers remotely. The distance to the end device does not matter. This makes WoL an asset for any company: Whether it’s for technical support, managing the company network, or ensuring a good service.
In particular, the maintenance of existing systems is always a challenge. After all, administrators want to install lengthy updates without disrupting regular work patterns in the company. The ability to turn on the computer at any time makes it easy to find the optimal time for this maintenance work. In digital customer service, on the other hand, support staff can connect to the relevant PCs. This makes it easy to solve customers’ problems remotely.
TeamViewer’s WoL tool therefore supports the company in a wide range of everyday tasks. The function itself is aimed at IT administrators, remote employees or technical support. Combined with the remote desktop functionality, the Wake-on-LAN supports immersive control over unattended devices. This allows the highest level of technical support to be provided with minimal disruption to business operations. At the same time, this functionality can be used not only on the PC, but also on mobile devices. As an overarching protocol, WoL supports TeamViewer on a wide range of operating systems and devices.
Want to give TeamViewer a try?
Key Benefits of Using Wake-on-LAN Software
Reduce the transport and personnel costs that come with having staff onsite to oversee machines and certify they are powered on and running. Moreover, reduce energy costs by ensuring only devices being used are switched on.
Whether you are looking to transfer files from your office computer while at home or need to run a critical update on a remote machine, using Wake-on-LAN is the ideal solution.
TeamViewer offers advanced security features such as a black screen option for the remote PC so no one can see what you are doing, and a sticky notes feature to inform the remote PC-user of the changes you have made.
How does Wake-on-LAN work?
TeamViewer’s Wake-on-LAN feature enables you to turn on a computer that is turned off or in sleep mode. This can be done via another computer within the same network or via its public address. The first method simply requires you to configure the hardware of the target computer and configure TeamViewer on it in order wake it up from another device connected on the network. For the second method, you’re required to configure the hardware of the target computer, then configure the router for port forwarding and configure TeamViewer in order to use Wake-on-LAN. It’s also possible to do via your tablet or smartphone
What port does Wake-on-LAN use?
Wake-on-LAN uses a UDP (User Datagram Protocol) port. Many utilities use ports 7 or 9, but you can use any port you like for WoL. The UDP port needs to be forwarded to all IP addresses behind your router—it’s not possible to forward it to a specific IP address. For the action to work, i.e. for the computer to wake up, the Wake-on-LAN packet must be forwarded to every device running behind your router. A device will only wake up if the information in the WoL packet matches it.
What are the advantages of Wake-on-LAN?
With the Wake-on-LAN feature from TeamViewer, you can remotely access and control devices no matter whether they’re switched on or off. This not only provides great flexibility in terms of 24/7 access to devices and resources, it can also improve energy efficiency since devices can be turned off when not in use. In this way, TeamViewer supports remote working and IT support in a comprehensive fashion.
How to set up Wake-on-Lan with TeamViewer
In order to successfully wake up a computer by Wake-on-LAN, its hardware must meet several requirements.
The following checklist ensures that the computer is suitable for Wake-on-LAN:
- The computer is connected to a power source.
- The computer’s network card supports Wake-on-LAN.
- The computer has an Internet connection.
- The computer is connected to the Internet via a network cable.
- The computer is in one of the following power states
Start > Sleep
Start > Hibernation
- Shut down (Soft off)
Start > Shut down (not supported unter Mac OS X)
If these requirements have been met, you can move on to configure your computer and the software in the next steps.