Why you need ssh ... Ever wondered ?

Many of us have got up the answer as "ssh is secure shell" . But when it  comes to  the realistic question - why ssh is required ? you get stuck with different answers. Don't worry you will get to know till the end to this blog.

 Let me  make it very simple  for you  ~

Ssh is a protocol (meaning - a set of rules) which helps you to  transfer the data between systems/machines in a very secure manner without any security breach.It has replaced at least  4 main protocols - telnet,ftp,vnc (partly), vpn (partly).With the encrypted keys mechanism,ssh helps you to securely login to other machines. These keys are public and private keys .

Now lets come back to the why part , why we need it ? So.. the outstanding capability of encrypting and transferring the data makes SSH  - the developers or administrators  first choice to use.You need to connect to other machine ! - use ssh , but how ?  check it ..  

      1. Generate a  key using ssh-keygen command , this command will                                  generate a public and  private key .

                                 

                       

     2. Copy the public key to all machines that you want to ssh or transfer the                    data:

        [hdp@nn1 ~]$ cat id_rsa.pub | ssh  username@machine 'cat >>                                            .ssh/authorized_keys'

              For-example :   username is 'hdp' and machine is 192.168.1.10, So your                                                  command will be  :

                 

                cat id_rsa.pub | ssh  hdp@192.168.1.10 'cat >> .ssh/authorized_keys'

            

•  id_rsa.pub  - Thus is a  public key file which is encrypted , it  will be copied to other   machines , this key is a available in .ssh location 

•  id.rsa - This  is a private  encrypted key file 

• authorized_keys - This File  is copied to the machines to which you want to connect or transfer the data securely . 

      3.   Now , last step is ssh to the machine you want to connect : 

So , you can check in 3rd step that on ssh 192.168.1.10 (machine host-name)  , it is successfully login us to the another machine .