This article explains briefly what WOL is and also provides Wake-On-LAN troubleshooting guidance and steps.
What is Wake-On-LAN (WOL)
Wake-On-LAN is an Ethernet networking standard that allows a properly configured network computer to be turned on or awakened by a network message. Wake-on-LAN (sometimes abbreviated WoL) is an industry standard protocol for waking computers up from a very low power mode remotely. The definition of "low power mode" means while the computer is "off" and has access to a power source. This is useful if you plan to access your computer remotely for any reason: it allows you to retain access to your files and programs, while keeping the PC in a low-power state.
The primary Ethernet port is usually on the side or the back of the system, and it is listed as Ethernet 1 when you run IPCONFIG. This is the port that supports Wake-On-LAN.
NOTE: Most modern systems are equipped with a RJ-45 network jack. Systems without an integrated network jack will need a USB Dongle that is WOL compliant. Ensure that any USB NIC Adapters are WOL capable, before any troubleshooting of the system.
Once you have confirmed that the network cable is connected to the NIC on the system, if Wake On LAN still doesn't function properly, troubleshoot using the following steps:
- Confirm that the AC power is plugged in. WOL does not work when the system is running on battery. This is by design.
- Confirm that the link light remains on when the system is powered off. If there is no link light, then there is no way for the NIC to receive the magic packet to wake the system.
- Ensure that WOL is enabled in the BIOS under Power Management settings.
- Ensure that Deep Sleep is disabled in the BIOS (not applicable to all systems). This power saving setting turns off the NIC.
- It may be necessary to boot to the Windows desktop after changing the BIOS settings in order for them to be properly applied. There is some interaction between the BIOS settings and the NIC driver settings in Windows 8.
- Check the NIC driver properties in Windows and ensure that WOL is enabled there. These settings can override the BIOS in Windows 8 or Windows 10.
- Confirm that the client system can be pinged by the system that is sending the magic packet.
- Confirm that the MAC address used in the magic packet matches the MAC for Ethernet 1 on the client system.
- If an IP address is specified in the magic packet, then the network switch may not properly broadcast it to the whole network. It may be necessary to change the address to broadcast the packet to the whole network. For example, if the client address is 192.168.1.12, the broadcast address used in the packet would be 192.168.1.255.
- Make sure the Power Management settings are configured correctly in the Ethernet driver properties, as shown in the examples below:
- Enable the following Power Management driver settings as shown for the Intel 82579LM Gigabit Network controller: Allow the computer to turn off this device to save power, Allow this device to wake the computer, and Only allow a magic packet to wake the computer (Figure 1):
Figure 1: Intel 82579LM Gigabit Network Controller Power Management settings
- The Power Management settings shown below for the Intel 82578DM should be configured with the settings Wake on Magic Packet and Wake on Pattern Match enabled, but the Power Save Option Reduce link speed during system idle disabled (Figure 2):
Figure 2: Intel 82578DM Gigabit Network Power Management settings
- If the Realtek PCIe GBE network adapter is installed on the system, then configure the Advanced driver properties for the following settings: Shutdown Wake-On-Lan / Enabled; Wake on Magic Packet / Enabled; Wake on pattern match / Enabled, and WOL & Shutdown Link Speed / 10 Mbps (Figure 3):
Figure 3: Realtek PCIe GBE NIC Advanced driver properties