centOS 7下更改完静态ip后发现network服务重启不了，尝试了各种方法，终于解决了。
报错消息：Job for network.service failed because the control process exited with error code.See "systemctl status network.service" and "journalctl -xe" for details.
解决办法：NetworkManager 服务有冲突，这个好解决，直接关闭 NetworkManger 服务就好了， service NetworkManager stop，并且禁止开机启动 chkconfig NetworkManager off 。之后重启就好了。
service NetworkManager stop
chkconfig NetworkManager off