Yyds dry inventory SSH Remote Connection introduction

SSH Introduction to remote connection

​ Most commonly provided Linux The tool for remote connection service is SSH Software .SSH It is divided into SSH Client and SSH There are two parts in the server , among ,SSH The software programs included in the server mainly include openssh and openssl. stay Linux In the system , You can query as follows SSH Installation of server tools ：

Log in and copy

      
      

       
       [
       
       root
       
       @
       
       www 
       
       ~]
       
       # rpm -qa openssh openssl
       
       

       
       openss1
       
       -
       
       1.0.2
       
       k
       
       -
       
       16.
       
       e17.
       
       x86_64
       
       

       
       openssh
       
       -
       
       7.4
       
       p1
       
       -
       
       16.
       
       el7.
       
       x86_64
      
      
      
      

       
       
1.
       
       
2.
       
       
3.
      
      

SSH Introduction to the server

​ start-up Linux System time , By default ,SSH The server program will start with the system ,SSH A service is a daemon （daemon）, It runs permanently in the background of the system and always responds to all SSH Client's connection request .SSH The process name of the server is sshd, Responsible for real-time monitoring of remote SSH The connection request of the client is processed , These requests generally include public key authentication 、 key exchange 、 Symmetric key encryption and insecure connection .SSH Service is Linux During system optimization, one of the services that need to be reserved is the self startup service .

SSH Client Introduction

​SSH The most commonly used tool on the client side is Windows Running on the platform SecureCRT 了 , The installation of the tool is simple , Follow the prompts step by step to complete the installation , Then open and register the software , It can be used after running . Remote connection Linux when , except SecureCRT Outside the client software , also Xshell、putty And Linux Under the SSH Wait for the client software .

​SSH The service side and SSH The communication between clients is through SSH Agreement to achieve .SSH Agreement is Secure ShellProtocol Abbreviation , from IETF Network working group （Network Working Group） To develop . Before data transmission ,SSH First, encrypt the online data packet through encryption technology , Then carry out data transmission , This will ensure the security of the transmitted data .SSH Is a security protocol designed for remote login sessions and other network services . utilize SSH The protocol can effectively prevent information leakage in the process of remote management , In the current production environment , It is widely used in most enterprises SSH Protocol service to replace the traditional insecure remote online service software , Such as telnet（23 port , Unencrypted ） etc. .SSH There are two incompatible versions of the Protocol , Namely SSH 1.x and SSH 2.x.openssh Support at the same time SSH 1.x and SSH 2.x. use SSH 2.x The client program of cannot connect to SSH 1.x Service procedures ,SSH2.x Than SSH1.x More secure , By default, the server passes SSH 2.x Agreement to provide services .