Mac OS X Leopard - ARCAism

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CHAPTER 21 WORKING WITH REMOTE SERVERS AND NETWORKS
Conspicuously absent as available protocol declarations in the Connect to Server window
are sftp, the Secure Shell File Transfer Protocol; svn, the Subversion file transfer protocol
(although Subversion can be transacted over other protocols, such as HTTP); and file, as used
in standard file URLs. The absence of file URLs is notable not because they have much meaning
in a dialog intended for connecting to servers but because they are used extensively throughout
the system. Using them in the Connect to Server window simply returns an error.
Connecting in Darwin
Although using a computer’s graphical interface via screen sharing is relatively new, the concept
of using one computer to log in to and control another computer remotely is anything but. UNIX
is, by its very nature, a remotely controllable operating system, and old-fashioned shell-to-shell
networking is very much alive in Terminal, as shown in Figure 21-3.
Figure 21-3. Remote computing by Secure Shell in Terminal
To connect to another machine, open Terminal from /Applications/Utilities. From the
command line, invoke ssh with the username and address of the machine you want to connect to,
separated by the “at” sign. For example, to connect to a machine at the local IP address 10.0.1.5
with the username booksystem, you would type this:
ssh booksystem@10.0.1.5
NOTE You don’t have to use a local IP address or an IP address at all. Anything that can be
resolved on the Internet is valid, including standard and local domain names.
If you are connecting to a machine for the first time, you will be asked whether it is safe to
proceed. Confirm this by typing yes. Unlike most UNIX programs, you have to type the entire
word. You will then be prompted for a password and then, assuming you can authenticate properly,
presented with a welcome message and the command prompt.
From this prompt you can create, delete, and alter files and folders, as well as list, run, and
kill processes. You can even launch new shells and Secure Shell into other servers. It’s the same as
if you were sitting at the remote machine typing into a Terminal window.