RHEL7虚拟机添加新网卡后，网卡无法启动
1.在开启网络时，有错误提示：
# systemctl restart network.service Job for network.service failed. See ‘systemctl status network.service‘ and ‘journalctl -xn‘ for details.
2.根据提示执行：提示错误日志如下
# 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 Sat 2015-07-04 13:41:38 CST; 13s ago Process: 3453 ExecStop=/etc/rc.d/init.d/network stop (code=exited, status=0/SUCCESS) Process: 4692 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE) Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com network[4692]: RTNETLINK answers: File exists Jul 04 13:41:38 rhce7.example.com systemd[1]: network.service: control process exited, code=exited status=1 Jul 04 13:41:38 rhce7.example.com systemd[1]: Failed to start LSB: Bring up/down networking. Jul 04 13:41:38 rhce7.example.com systemd[1]: Unit network.service entered failed state. #
3.用 ip addr 命令查看MAC地址与文件/etc/sysconfig/network-scripts/ifcfg-enp0s8中显示的不一致。
4.修改/etc/sysconfig/netwrok-scripts/ifcfg-enp0s8 中HWADDR= * :*:*:*:*:* (也就是用IP ADDR 命令所查到的MAC）
5.重启系统
原文：http://www.cnblogs.com/abclife/p/4619920.html