centos 7：network: 正在打开接口 ens33： 错误：激活连接失败：No suitable device found for this connection.

Mar 11 10:18:18 localhost systemd: Starting LSB: Bring up/down networking...
Mar 11 10:18:19 localhost network: 正在打开环回接口： [  确定  ]
Mar 11 10:18:19 localhost NetworkManager[9366]: <info>  [1552270699.1055] audit: op="connection-activate" uuid="fd005f04-41ac-4401-bd27-decd3492dd84" name="ens33" result="fail" reason="No suitable device found for this connection."
Mar 11 10:18:19 localhost network: 正在打开接口 ens33： 错误：激活连接失败：No suitable device found for this connection.
Mar 11 10:18:19 localhost network: [失败]
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost network: RTNETLINK answers: File exists
Mar 11 10:18:19 localhost systemd: network.service: control process exited, code=exited status=1
Mar 11 10:18:19 localhost systemd: Failed to start LSB: Bring up/down networking.
Mar 11 10:18:19 localhost systemd: Unit network.service entered failed state.
Mar 11 10:18:19 localhost systemd: network.service failed.

解决办法：

1. 如果新加网卡或者克隆虚拟机，可能是 mac 地址不对，使用 ip addr 查看mac地址

• • 永久修改：

然后把  /etc/sysconfig/network-scripts/ifcfg-ens33（MACADDR） 或者 /sys/class/net/ens33/address

• • 临时修改：

#ifconfig eth0 down /*禁掉eth0网卡，这里以eth0网卡为例*/

#ifconfig eth0 hw ether 00:AA:BB:CC:DD:EE /*修改eth0网卡的MAC地址*/

#ifconfig eth0 up   /*重新启动eth0网卡*/

        2. Mac 没问题，关闭系统的 NetworkManager ， 注意大小写