If you are new to dedicated servers, your primary experience with hosting management has probably been from within the comfortable pages of a web-based control panel. Without a doubt, control panels like cPanel/WHM provide system administrators with robust tools to tackle most of the issues they may encounter. Nevertheless, there will still be times when you will need to get a little more intimate with your server. SSH is just the tool for the job.
SSH stands for SecureShell and is a secure method of accessing a Linux or Unix server remotely. When you login to your server via SSH, you are logging into the system shell, a virtual console that is essentially like standing in front of the server with a keyboard and screen. From within SSH, you can control every aspect of your server’s operating system. This makes it both powerful and dangerous.
By default any user with shell login access can also login via SSH. That includes the root administrator user. Therefore, as a safety precaution, you should not login to your server directly as root, and you can even configure the server to deny root login attempts. Instead, you can login as a user with limited privileges and then either use “sudo” or “su” to become root when the need arises.
SSH has a variety of other uses beyond command line access. You can use it to provide secure encrypted transfer of files, for tunneling various other protocols, and for secure backups of your server through rsync. SSH is a versatile and powerful tool, and once you get the hang of it, you will likely use it on a regular basis.