SSH is a network protocol that provides secure access to a computer. When we need to connect to a remote computer via SSH, that computer should have a SSH server running on it. There are different ways a client can authenticate itself to the server. A typical authentication mode will be to enter a password when logging into a remote system.
Using the below mentioned steps we can directly login to Linux server without password authentication step.
First we will need to download PuTTY and PuTTYgen.
PuTTY: the Telnet and SSH client itself.
PuTTYgen: an RSA and DSA key generation utility.
>> Download the latest version of putty.exe and puttygen.exe and start puttygen.exe.
>> We need to generate a key for this process. Puttygen window will appear. Leave the default ‘SSH-2 RSA’ selection. Select the option “Generate”.
>> Select “Save private key” and save the file in a suitable location. Then open the file and select the key written under “Public-Lines 6:”
>> Open putty and type the IP of Linux server and enter into the server using password.
>> Then go to home directory and create a file “authorised_keys” using vi editor in “~/.ssh” directory and paste the key in the file.
>> Change the permission of the file using the command “chmod 600 ~/.ssh/authorized_keys”.
>> Open putty.exe type the IP and then select the option “Connection >> Data”. Type the “Auto-login username” (the username we user for login).
>> Select the option “SSH >>Auth” and browse the key file.
>> Select open.
Finally we will be able to login without using password.