众所周知 Ubuntu 通常使用 netplan 作为网卡配置前端，所有的修改应该通过 /etc/netplan/xxxx.yaml 实现！！！

所以不应该编辑 /etc/network/interfaces 或者乱写什么 systemd 配置，反正不会被保存

所以涉及下列操作的教程都是错的：

• 写任何启动脚本运行 ethtool -s %i wol g

参考配置 sudo nano /etc/netplan/50-cloud-init.yaml ：

# This file is generated from information provided by the datasource.  Changes
# to it will not persist across an instance reboot.  To disable cloud-init's
# network configuration capabilities, write a file
# /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following:
# network: {config: disabled}
network:
    ethernets:
        enp5s0:
            dhcp4: true
            wakeonlan: true # <--- 要点在这里啊
    version: 2

编辑后使用 sudo netplan try 测试，没有问题回车保存

这个功能是防止你乱改以后连不上服务器的，超时没有确认就会自动回撤配置并应用，只有修改好后确认能连上才会保存

然后通过 sudo ethtool <> 检查 WOL 是否开启：

xiwu@hana:~$ sudo ethtool enp5s0 
Settings for enp5s0:
	Supported ports: [ TP	 MII ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Supported pause frame use: Symmetric Receive-only
	Supports auto-negotiation: Yes
	Supported FEC modes: Not reported
	Advertised link modes:  10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Advertised pause frame use: Symmetric Receive-only
	Advertised auto-negotiation: Yes
	Advertised FEC modes: Not reported
	Link partner advertised link modes:  10baseT/Half 10baseT/Full
	                                     100baseT/Half 100baseT/Full
	                                     1000baseT/Half 1000baseT/Full
	Link partner advertised pause frame use: No
	Link partner advertised auto-negotiation: Yes
	Link partner advertised FEC modes: Not reported
	Speed: 1000Mb/s
	Duplex: Full
	Auto-negotiation: on
	master-slave cfg: preferred slave
	master-slave status: slave
	Port: Twisted Pair
	PHYAD: 0
	Transceiver: external
	MDI-X: Unknown
	Supports Wake-on: pumbg
	Wake-on: g # <--- 此处为 g 说明开启，d 是支持但未开启，其他的全是失败自行查询
	Link detected: yes