华为云开机器，Network device unmanaged，导致无法连接且不通外网

故障现象：

1. 服务器无法被ping通

2. 服务器无法通外网

3. ipaddr 网卡没地址

[root@xiamingliang ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 00:0c:29:c1:69:35 brd ff:ff:ff:ff:ff:ff
    altname enp3s0
3: br-1c57ae1d2940: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default 
    link/ether 02:42:3a:6b:40:d9 brd ff:ff:ff:ff:ff:ff
    inet 172.20.0.1/16 brd 172.20.255.255 scope global br-1c57ae1d2940
       valid_lft forever preferred_lft forever
……

4.nmcli device status状态为unmanaged

[root@xiamingliang ~]# nmcli connection show 
NAME    UUID                                  TYPE      DEVICE 
ens160  cf32e4bc-eaf9-3db0-98bb-2879bd5153d8  ethernet  --     
[root@xiamingliang ~]#

5. nmcli connection show状态为unmanaged

[root@xiamingliang ~]# nmcli connection show 
NAME    UUID                                  TYPE      DEVICE 
ens160  cf32e4bc-eaf9-3db0-98bb-2879bd5153d8  ethernet  --     
[root@xiamingliang ~]#

6. 执行下面命令修复即可

nmcli connection up ens160

如果修复不了，参考文章https://blog.51cto.com/mlxia/5765714

我也很纳闷，重启NetworkManager没用，重启服务器也没用...