OpenSSH is a free open source set of computer tools used to provide secure and encrypted communication over a computer network by using the ssh protocol. Accessing a shell account via SSH may be one of the most secure and easiest ways to access files, run programs, or change system settings. With secure shell it is only possible to run commands in a command line environment, not graphically.
Step 1 - First change to root user.
Step 2 - To install OpenSSH, open a terminal and run the below command.
apt-get install openssh-server openssh-client
Also we can use graphically, go to "Ubuntu Software Center" use below example.
Step 3 - After installing we can see the ssh configuration directory.
Step 4 - Before editing configuration file, backup the sshd_config file.
Step 5 - Now, we can configure ssh configuration file according to our requirement by using "gedit" or "vim".
Note : Here I am using default ssh settings.
Step 6 - After configuration, restart the sshd service.
Step 7 - After configuration go to client / remote PC and connect to server using "putty" or "terminal".
Here I successfully connected, now I can use my server using ssh.
This method is by using terminal.