Ubuntu 18.04
$ sudo apt install net-tools
$ sudo atp-get install ethtool
使用 ipconfig 查看 LAN 卡名稱：
$ ifconfig docker0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0 ether 02:42:c8:22:33:44 txqueuelen 0 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 enp1s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.101 netmask 255.255.255.0 broadcast 192.168.1.255 inet6 fe80::28db:9357:aa77:f13 prefixlen 64 scopeid 0x20<link> ether 33:9c:52:07:66:88 txqueuelen 1000 (Ethernet) RX packets 25517 bytes 2338698 (2.3 MB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 46529 bytes 14797516 (14.7 MB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1000 (Local Loopback) RX packets 328 bytes 23053 (23.0 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 328 bytes 23053 (23.0 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
docker0：給 Docker 用的虛擬網卡
lo： 為 Loopback
enp1s0： 真正的網卡名稱
有了網卡名稱再使用 ethtool <網卡名稱> 察看網卡狀態：
$ sudo ethtool enp1s0 Settings for enp1s0: Supported ports: [ TP MII ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Half 1000baseT/Full Supported pause frame use: No Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Half 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/Full Link partner advertised pause frame use: Symmetric Link partner advertised auto-negotiation: Yes Link partner advertised FEC modes: Not reported Speed: 1000Mb/s Duplex: Full Port: MII PHYAD: 0 Transceiver: internal Auto-negotiation: on Supports Wake-on: pumbg Wake-on: d Current message level: 0x00000033 (51) drv probe ifdown ifup Link detected: yes
其中 Wake-on 就是網卡WOL狀態， d = Disable, g = Enable。
啟用網卡 WOL 功能：
$ sudo ethtool -s enp1s0 wol g
啟用後實測確時可以喚醒電腦，但要注意是當系統重開機 Wake-on 狀態就會又跳回 Disable 了。
如果要讓系統每次開機都能自動啟用 WOL，可以這樣做：
- 建立一 wol service 檔案
/etc/systemd/system/wol@.service，內容如下：
[Unit] Description=Wake-on-LAN for %i Requires=network.target After=network.target [Service] ExecStart=/sbin/ethtool -s %i wol g Type=oneshot [Install] WantedBy=multi-user.target
2. 啟用 wol service (將 enp1s0 改為實際網卡名稱)
$ systemctl enable wol@enp1s0 Created symlink /etc/systemd/system/multi-user.target.wants/wol@enp1s0.service → /etc/systemd/system/wol@.service.
3. 檢查 wol service 是否啟用
$ systemctl is-enabled wol@enp1s0 enabled
4. 重開機然後再檢查一次 walk-on 狀態
$ sudo ethtool enp1s0
可以看到 WOL 在重開機後已正確啟用
walk-on: g