Configure SSH and Use putty for remote-control-优快云博客

本文介绍SSH（Secure Shell Protocol）的概念及其在服务器上的安装步骤。首先解释了SSH是一种通过不安全网络进行远程登录的安全协议。接着详细说明了如何检查当前网络连接状态、安装SSH服务端并使用Putty客户端进行连接。

Firstly, what is SSH?Which is a abbreviation of "Secure Shell Protocol", it is a protocol that support remote logon through insecure network. So, if we want to use putty on a client. we should install that ssh on the server side.

1) check the active internet connections

~# netstat -at

The result will be all(-a) the socket using TCP protocol. But there is no socket listening at ssh port (default 22). That is to say, if we run

~# netstat -at | grep ssh

there will be none.

2) install the ssh

sudo apt-get install ssh

this process will take several minutes and it will ask "Yes or no" question. Of course yes.

After that, you can check the connections again as 1). This time the result can include the ssh connection which is at LISTEN state.

3) Use putty on your client

Ok, putty connection use ssh protocal. Input the server Ip address or Host name. Click "open", that will be great.

At last, if ssh has been installed , but it is not at LISTEN state, you can restart is.

~# sudo /etc/init.d/sshd restart