class
N.scs.cs.nyu.edu
for various
values of N. When first starting out, you should generally log
into class.scs.cs.nyu.edu
which will automatically select
an unloaded machine.
Your logname and password on these machines should be what you specified on the first day of class. If not, please contact the instructor.
ssh
command. For example, if your username is
``student'', you can run the command:
dept 1% ssh class.scs.cs.nyu.edu -l student
student@class.scs.cs.nyu.edu's password:
Authentication successful.
Last login: Mon Jan 15 18:39:16 2001 from orchard.scs.cs.n
...
class2 1%
If you have problems with ssh, try running ssh1
instead:
dept 2% ssh1 class.scs.cs.nyu.edu -l student
If you are using X-windows, ssh can forward connections to your
X-server. If your ssh is not configured to do this by default, use
the -Y flag. For older versions of ssh, you
will need to use the -X (capital X) flag.
When X is forwarded, your DISPLAY environment
variable should be automatically set.
dept 1% ssh -Y class.scs.cs.nyu.edu -l student student@class.scs.cs.nyu.edu's password: Authentication successful. Last login: Mon Jan 15 18:39:16 2001 from orchard.scs.cs.n ... class2 1% echo $DISPLAY class2.scs.cs.nyu.edu:2.0 class2 2%
For X windows forwarding, you will need to run the Cygwin X server, and run ssh from within an xterm window.
Click the logo to download the installation program directly:
Note: some versions of MacOS X apparently set the DISPLAY environment variable to the value 0:0, which confuses the ssh client. If this is the case, you will need to change the DISPLAY to :0 before running ssh. Do so with the command export DISPLAY=:0 for sh/bash or setenv DISPLAY :0 for csh/tcsh.
You can copy files to and from the class machines using the
scp
program which comes with ssh. If plain scp does not
work, try using the -1
flag which uses version 1 of the
ssh protocol. For example, to copy the file testfile
to
the work/
subdirectory of your home directory on the
class machines, you can run the following:
dept 1% scp -1 testfile dm@class2.scs.cs.nyu.edu:work/
scp: warning: Executing scp1 compatibility.
Host key not found from the list of known hosts.
Are you sure you want to continue connecting (yes/no)? yes
Host 'class2.scs.cs.nyu.edu' added to the list of known hosts.
dm@class2.scs.cs.nyu.edu's password:
testfile | 1 KB | 1.0 kB/s | ETA: 00:00:00 | 100%
dept 2%
Newer versions of SSH also come with a utility called sftp, which acts like the ftp file transfer utility. Some people may prefer this interface.
class.scs.cs.nyu.edu
you will automatically get a
lightly-loaded machine. You can also manually look for an unused
machine with the ruptime
command. For example:
class2 1% ruptime
class1 up 3+01:12, 3 users, load 0.25, 0.13, 0.13
class2 up 3+02:58, 1 user, load 0.10, 0.09, 0.08
class3 up 3+02:57, 0 users, load 0.10, 0.09, 0.08
class4 up 3+02:57, 0 users, load 0.12, 0.09, 0.08
class5 up 3+02:56, 0 users, load 0.07, 0.08, 0.08
class2 2%
This shows that machines class3
, class4
, and
class5
are unused.
classN
, you can make yourself a local scratch
directory under /home/cN/scratch
. (These directories are
accessible from all the machines, but it is fastest to use local disk
space.) Note that these directories are not backed up. Never leave important files in the scratch
directories. The scratch space is meant for things like
compiler output that can be recreated if necessary.
Since your assignments will mostly be in the Unix environment, you may find it convenient to run the X-windows system to have multiple unix windows open on various machines. You have two options for running X-windows.
To use Vnc, you first start a vnc server:
class2 1% vncserver You will require a password to access your desktops. Password: [enter a password here] Verify: [re-type pasword] New 'X' desktop is class2.scs.cs.nyu.edu:1 Creating default startup script /home/c/dm/.vnc/xstartup Starting applications specified in /home/c/dm/.vnc/xstartup Log file is /home/c/dm/.vnc/class2.scs.cs.nyu.edu:1.log class2 2%
vncpasswd
.
class2.scs.cs.nyu.edu:1
in
this example.
You can access the vnc server from any web browser with java. Simply
add 5800 to the number of the X display, and use this as a URL. In
the example, the display is class2.scs.cs.nyu.edu:1
,
thus, you can access the server as http://class2.scs.cs.nyu.edu:5801.
To get better performance, you can download a native Vnc viewer which will be much faster than the web browser interface. Native viewers are available for both Windows and MacOS. We recommend downloading TightVNC for Windows, or Chicken of the VNC for MacOSX. Local NYU copies of these files are available here: