Networking 流浪汉可以'；更换网络后无法启动

我使用vagrant按照以下指南安装KVM：

此处更改了桥接网络：

步骤3：配置桥接网络

当我重新启动vagrant时，它总是停在这里：

$ vagrant up                                                                  
==> default: Attempting graceful shutdown of VM...                                
    default: Guest communication could not be established! This is usually because
    default: SSH is not running, the authentication information was changed,      
    default: or some other networking issue. Vagrant will force halt, if          
    default: capable.                                                             
==> default: Forcing shutdown of VM...                                            
==> default: Clearing any previously set forwarded ports...                       
==> default: Clearing any previously set network interfaces...                    
==> default: Preparing network interfaces based on configuration...               
    default: Adapter 1: nat                                                       
    default: Adapter 2: hostonly                                                  
==> default: Forwarding ports...                                                  
    default: 22 (guest) => 2222 (host) (adapter 1)                                
==> default: Running 'pre-boot' VM customizations...                              
==> default: Booting VM...                                                        
==> default: Waiting for machine to boot. This may take a few minutes...          
    default: SSH address: 127.0.0.1:2222                                          
    default: SSH username: vagrant                                                
    default: SSH auth method: private key                                         
Timed out while waiting for the machine to boot. This means that                  
Vagrant was unable to communicate with the guest machine within                   
the configured ("config.vm.boot_timeout" value) time period.                      

If you look above, you should be able to see the error(s) that                    
Vagrant had when attempting to connect to the machine. These errors               
are usually good hints as to what may be wrong.                                   

If you're using a custom box, make sure that networking is properly               
working and you're able to connect to the machine. It is a common                 
problem that networking isn't setup properly in these boxes.                      
Verify that authentication configurations are also setup properly,                
as well.                                                                          

If the box appears to be booting properly, you may want to increase               
the timeout ("config.vm.boot_timeout") value.

---

如何修复它？

如果您正在使用vagrant，您不需要进行这些修改，您只需在vagrant文件中更改网络配置（请参阅）并进行更改

Vagrant.configure("2") do |config|
  ...
  config.vm.network "public_network"
  ...
end

vagrant将注意更新正确的配置文件

Vagrant.configure("2") do |config|
  ...
  config.vm.network "public_network"
  ...
end