Centos 7 开机后无法联网

无法ping,connect: Network is unreachable

ping: baidu.com: Name or service not known

nmtui无法激活网卡

sudo dhclient 解决，重启后继续失败

systemctl status network.service 显示

● network.service - LSB: Bring up/down networking

  Loaded: loaded (/etc/rc.d/init.d/network; bad; vendor preset: disabled)
  Active: failed (Result: exit-code) since Fri 2018-04-27 15:52:50 CST; 3min 6s ago
  Docs: man:systemd-sysv-generator(8)

  Process: 827 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE)

解决方法：https://blog.csdn.net/imred/article/details/53493109

systemctl stop NetworkManager

systemctl disable NetworkManager

Removed symlink /etc/systemd/system/multi-user.target.wants/NetworkManager.service.

Removed symlink /etc/systemd/system/dbus-org.freedesktop.NetworkManager.service.

Removed symlink /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service.

重新启动网络：

systemctl start network.service