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