解决centos7虚拟机 Failed to start LSB: Bring up/down networking问题

情景：1 克隆虚拟机  mac不冲突 （网上说克隆会引起mac冲突）

          2 虚拟机长时间挂起 （可能是主要原因，不明情形导致网卡关闭 并且重启不了）

网卡报错信息

[root@zk01 ~]# systemctl status network.service
network.service - LSB: Bring up/down networking
   Loaded: loaded (/etc/rc.d/init.d/network)
   Active: failed (Result: exit-code) since 六 2018-06-02 10:51:40 CST; 7min ago
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 network[841]: RTNETLINK answers: File exists
6月 02 10:51:40 zk01 systemd[1]: network.service: control process exited, code=exited 
status=1
6月 02 10:51:40 zk01 systemd[1]: Failed to start LSB: Bring up/down networking.
6月 02 10:51:40 zk01 systemd[1]: Unit network.service entered failed state.

解决方案：

重启虚拟机！