开启 NetworkManager 

cat <<EOF >/etc/NetworkManager/nm-system-settings.conf
[main]
plugins=ifupdown,keyfile
[ifupdown]
managed=true
EOF
systemctl start NetworkManager
systemctl enable NetworkManager

关闭 NetworkManager 

systemctl stop NetworkManager 
systemctl disable NetworkManager 
rm -rf /var/lib/NetworkManager/NetworkManager.state /etc/NetworkManager/nm-system-settings.conf
reboot

/etc/NetworkManager/nm-system-settings.conf 是NetworkManager的配置文件

/etc/NetworkManager/nm-system-settings.conf 是NetworkManager的状态文件