What Is SSH?
One essential tool to master as a system administrator is SSH.
SSH, or Secure Shell, is a protocol used to securely log onto remote systems. It is the most common way to access remote Linux and Unix-like servers, such as VPS instances.
In this guide, we will discuss how to use SSH to connect to a remote system.
The tool on Linux for connecting to a remote system using SSH is called, unsurprisingly, ssh.
The most basic form of the command is:
The remote_host in this example is the IP address or domain name that you are trying to connect to.
This command assumes that your username on the remote system is the same as your username on your local system.
If your username is different on the remote system, you can specify it by using this syntax:
Once you have connected to the server, you will probably be asked to verify your identity by providing a password.
Later, we will cover how to generate keys to use instead of passwords.
To exit back into your local session, simply type:
How Does SSH Work?
SSH works by connecting a client program to an ssh server.
In the above commands, ssh is the client program. The ssh server is already running on the remote_host that we specified.