# Setting Up Wake-on-LAN (WOL) in Linux


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## Setting Up WOL

First, you need to check that the **Wake on LAN** feature is enabled in the BIOS/UEFI. 
Next, install `ethtool` and check the settings.
Specify the name of the network interface that can wake up the computer. You can view existing ones with the command `ip a`.

```shell
sudo apt update && sudo apt install ethtool
sudo ethtool enp8s0 | grep "Wake-on"
```
If the output shows the value **d**, it means the mode is disabled. 
Change the mode to **Wake on MagicPacket** — **g**. You can find more about the modes in the [documentation](https://man7.org/linux/man-pages/man8/ethtool.8.html).

```shell
sudo ethtool --change enp8s0 wol g
```

The problem with manual changes is that it only works until the system is rebooted. 
Therefore, you need to add it to the startup using one of the following methods:

### Netplan

In your configuration, for example in `/etc/netplan/10-init.yaml`, you need to add the `wakeonlan` option.

```yaml
network:
  version: 2
  ethernets:
    enp8s0:
      dhcp4: true
      wakeonlan: true
```

### Interfaces

In your configuration, for example in `/etc/network/interfaces`, you need to add the `ethernet-wol` option.

```ini
auto enp8s0
iface enp8s0 inet dhcp
        ethernet-wol g
```

### NetworkManager

You need to check what your connection is called in the system and change its operation mode.

```shell
nmcli con show
sudo nmcli c modify "netplan-enp8s0" 802-3-ethernet.wake-on-lan magic
nmcli c show "netplan-enp8s0" | grep 802-3-eth
```

### Systemd-networkd

Check your interfaces and adjust the necessary one.

```shell
networkctl list
sudo networkctl edit enp8s0
```

And add the option

```ini
[Link]
WakeOnLan=magic
```

Then activate the changes

```shell
sudo networkctl reload
sudo networkctl reconfigure
```

### Systemd

If the previous options did not work for some reason, you can do this through **systemd**.

Create a new service

```shell
sudo systemctl edit wol.service --full --force
```

And add the setting for **Wake on MagicPacket**.

```ini
[Unit]
Description=Enable Wake-on-LAN
After=network-online.target
[Service]
Type=oneshot
ExecStart=/sbin/ethtool --change enp8s0 wol g
[Install]
WantedBy=network-online.target
```

Reload the modified service configurations and start it.

```shell
sudo systemctl daemon-reload
sudo systemctl enable wol.service
sudo systemctl start wol.service
systemctl status wol
```

## Checking Functionality

Put your computer to sleep with `sudo systemctl suspend` or turn it off with `sudo systemctl poweroff`. 
The indicator on the computer's network card may not light up, depending on the manufacturer, 
but it must be lit on the switch (even if it's yellow), otherwise the magic packets will not reach your network card.

Next, from another computer, send the command to turn it on, specifying the MAC address of the computer to be turned on.

```shell
sudo apt update && sudo apt install etherwake
sudo etherwake -i ens3 11:22:33:44:55:66
```