解决【ens33】这个网卡一直无法激活问题

CentOS的启动出错：

当执行 ifup ens33

出现错误：

[root@localhost ~]# ifup ens33
Error: Connection activation failed: No suitable device found for this connection (device lo not available because device is strictly unmanaged).

解决办法：

[root@localhost ~]# chkconfig NetworkManager off
Note: Forwarding request to 'systemctl disable NetworkManager.service'.
Removed symlink /etc/systemd/system/multi-user.target.wants/NetworkManager.service.
Removed symlink /etc/systemd/system/dbus-org.freedesktop.NetworkManager.service.
Removed symlink /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service.
Removed symlink /etc/systemd/system/network-online.target.wants/NetworkManager-wait-online.service.

[root@localhost ~]# chkconfig network on

[root@localhost ~]# service NetworkManager stop
Redirecting to /bin/systemctl stop NetworkManager.service

[root@localhost ~]# service network start
Starting network (via systemctl):                          [  OK  ]

然后