Interact with a remote machine from the command line via SSH, the Secure Shell.
Once you’ve acquired a taste of the Unix command line underlying Mac OS X, it’s hard to stick only to the machine at hand. You want to log in to that old-but-upgraded PowerMac 7500 with G3 card in the closet to see how your web server’s faring. Your friend invites you to drop in on his X Server across the country to check out his latest Perl hacks. The FTP server in your office doesn’t appear to be allowing incoming FTP requests, despite being pingable (read: online and alive).
Forget remote screen-sharing applications; who needs a candy-coated graphical user interface to accomplish the remote administration tasks at hand? From the command line you can do most anything you can do locally — except play that addictive new fully immersive GUI game you left in your office machine’s CD drive.
SSH, the Secure Shell, is a command-line utility for interacting with a computer over the network as if it were local, attached directly to your keyboard. SSH differs from other remote access options (e.g., Telnet) in its focus on security; all communication is encrypted, end to end. This means that anyone tapped into your network (called a man-in-the-middle attack) won’t see much more than gibberish floating by. And it does this in a fast, safe, and intuitive way, making for some interesting and powerful hacks.
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