CentOS 8重启后网卡不见了解决办法

1、问题描述

   CentOS 8重启后网卡不见了，也无法上网。

2、尝试用nmcli connection up ens160命令修复，提示 unmanaged

[root@compute02 network-scripts]# nmcli connection up ens160

Error: Connection activation failed: No suitable device found for this connection (device lo not available because device is strictly unmanaged).

3、通过nmcli device status 命令查询了一下设备状态，为unmanaged

[root@compute02 network-scripts]# nmcli device status 

DEVICE  TYPE      STATE      CONNECTION 

virbr0  bridge    unmanaged  --         

ens160  ethernet  unmanaged  --         

ens192  ethernet  unmanaged  --         

lo      loopback  unmanaged  --         

4、确定NetworkManager是否已接管了系统的网络连接管理，发现是disabled 

[root@compute02 network-scripts]# nmcli networking 

disabled

5、手动开启，问题解决

[root@compute02 network-scripts]# nmcli networking on

[root@compute02 network-scripts]# ping www.baidu.com

PING www.a.shifen.com (14.119.104.254) 56(84) bytes of data.

64 bytes from 14.119.104.254 (14.119.104.254): icmp_seq=1 ttl=50 time=20.8 ms

64 bytes from 14.119.104.254 (14.119.104.254): icmp_seq=2 ttl=50 time=20.2 ms

64 bytes from 14.119.104.254 (14.119.104.254): icmp_seq=3 ttl=50 time=19.9 ms

64 bytes from 14.119.104.254 (14.119.104.254): icmp_seq=4 ttl=50 time=20.0 ms