A virtual machine that has been running normally. After a shutdown and restart, it is found that SSH cannot connect

Restart network discovery failed

service networkrestart

Solution:

[root@lexsaints ~]#systemctl stop NetworkManager
[root@lexsaints ~]#systemctl disable NetworkManager
[root@lexsaints ~]#systemctl restart  network
or
[root@lexsaints ~]#systemctl  restart NetworkManager
[root@lexsaints ~]#systemctl restart  network

Cause of problem

NetworkManager is a program that detects the network and automatically connects to the network.

Whether it’s wireless or wired, it makes it easy for you to manage.

For wireless networks, the network manager can automatically switch to the most reliable wireless network.

The program using the network manager can freely switch between online and offline modes.

The network manager can preferentially select wired network and support VPN.

The network manager was originally developed by RedHat and is now managed by gnome.