Connection established.
To escape to local shell, press 'Ctrl+Alt+]'.
Connection closing...Socket close.
Connection closed by foreign host.
Disconnected from remote host(我的阿里云) at
具体原因尚不清楚！
只知道去阿里云的控制台 > 点击实例名称 > 左侧【本实例远程命令】
发送远程命令
输入命令：chmod 400 /etc/ssh/*
