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As
of April 2001, the Eastman Computer Music Center will only allow remote
access to our UNIX and Linux machines by means of ssh client
applications. (ssh is pronounced
"s-shell" and stands for "secure shell") All other client services
formerly used to allow remote access, such as telnet, ftp, rlogin and rcp,
have been disabled or removed.
All
ECMC machines are equipped with current versions of ssh.
In order to access the ECMC Linux and Macintosh machines from your home or
other computer systems, the remote (home) system MUST
have an ssh client application installed. ssh client applications
for Linux, Unix, Windows and Macintosh platforms
are available at no charged at www.openssh.com or www.openssh.org. .
If you plan to work from home, be sure to read up on ssh for
your home system.
ECMC users should consult sections 6.3 and 6.4 of the ECMC USERS' GUIDE
for detailed information on using ssh, generating and distributing key
pairs and a passphrase, and copying files to and from ECMC computer systems.
The ECMC staff can answer any questions you might
have.
Read
on for some quick ssh and scp usage illustrations...
---------- Remote logins via ssh: --------------
To
log into an ECMC machine via ssh, type the following command line:
ssh
[-l <user_name>] <machine_name>
The -l user_name flag and argument only are necessary if your UID
(login name) differ on the remote and ECMC systems.
After
this, you should be prompted for you password or passphrase.
Example: User fred want to log on from his personal computer to
madking. From the comfort of his home, he types:
ssh -l fred madking.esm.rochester.edu
Note: This example uses only the first level of ssh security -- encryption.
Greater security, and, ultimately, greater ease of use, will result if fred
takes the time to generate public and private keys on his home system,
and distributes the public key to madking and all other machines that
he regularly access remotely. See section 6.3 of the ECMC USERS' GUIDE
for details.
------------ Transferring files via scp: ----------------
The
syntax for scp ("Secure CoPy")
is similar to that of rcp (which means it is ugly).
Here is an example :
scp
<file_name> <user_name>@<machine_name>:/<full_directory_path>/.
This
line will "put" a file from the machine you're using onto a remote machine.
The computer will need password verification every time you use this command
unless you have copied the public key from your home system to the remote system
.
So, to copy a soundfile from his home system to his soundfile directory on madking,
our friend fred could type:
scp soundfilename fred@madking.esm.rochester.edu:/snd/fred/.
Below is an example that demonstrates the opposite process -- copying a file
from an ECMC machine to a remote system:
scp
<UID>@<machine_name>:/<full_dir_path_plus_file_name> /<full_dir_path_of_destination>/.
To copy a file from his home Unix directory on arcana to his current
directory on his home system, fred types:
scp fred@arcana.esm.rochester.edu:/u/comp/fred/filename .
Note that there are ECMC scripts and ssh-compatible graphical applications
that can spare you from the gnarly syntax of scp, but it is good
to know this syntax so that you can use it in a pinch.
Security is an ever-present issue. This page will be updated with
new information whenever changes in security and remote access process are
made to the ECMC systems.. |