AWS服务器在XShell上的连接问题

遇到问题：

Connecting to 服务器IP...

Connection established.
To escape to local shell, press 'Ctrl+Alt+]'.
Connection closing...Socket close.
Connection closed by foreign host.
Disconnected from remote host(连接名) at 11:05:26.

Type `help' to learn how to use Xshell prompt.

解决方案：（修改权限）

[root@ip-XX~]# cd /etc/ssh  
[root@ip-XX ssh]# sudo chmod 644 ./* 
[root@ip-XX ssh]# sudo chmod 600 ssh_host_dsa_key 
[root@ip-XX ssh]# sudo chmod 600 ssh_host_rsa_key  
[root@ip-XX ssh]# sudo chmod 755 .  
[root@ip-XX ssh]# /etc/init.d/sshd restart