To wake up a server using Wake-on-LAN (WOL) on a FreeBSD system, you can use the ether-wake command. This command is used to send a Wake-on-LAN packet to a network device to power it on.
To use ether-wake, you need to know the MAC address of the network device you want to wake up. You can find the MAC address by looking at the device's network settings or by using a network scanning tool.
Once you have the MAC address, you can use the following command to send a Wake-on-LAN packet to the device:
ether-wake -i interface MAC_address
Replace interface with the name of the network interface (e.g. em0) and MAC_address with the MAC address of the device.
For example, to wake up a device with the MAC address 00:11:22:33:44:55 on the em0 interface, you can use the following command:
ether-wake -i em0 00:11:22:33:44:55
This will send a Wake-on-LAN packet to the device, which should power it on.
Note that the device must be configured to support Wake-on-LAN and must be connected to the network for this to work.