>ssh-keygen -t rsa (In Remote Machine)
>ls /root/.ssh
> id_rsa id_rsa.pub
> cat id_rsa.pub >> authorized_keys
> ls
> id_rsa id_rsa.pub authorized_keys
Now copy the id_rsa file into the $HOME/.ssh/ directory of the client machine.
> ssh root@server_ip_address
or
Copy the id_rsa file into the any location of the client machine
>ssh -i location/id_rsa root@server_ip_address