NMRFAM policy for secure remote access to facility spectrometers.
To enter the NMRFAM computer network you must ssh to login1.nmrfam.wisc.edu (or login2.nmrfam.wisc.edu) and only then will you be able to access other facility computers. To run the spectrometers you will need to tunnel VNC through ssh. The easiest way to do that (especially from Windows) is by using SSVNC.
SSVNC is a standalone Java VNC viewer with a clean and easy to use interface for Windows, Mac OS X, and Unix that automatically starts up a tunnel for SSH/SSL connections to any VNC server, and then launches the VNC Viewer to use the encrypted tunnel:
Logging in to a spectrometer or other NMRFAM computer from Windows
Download and use putty.exe (google it) to connect securely (through SSH) to login1.nmrfam.wisc.edu (or login2)
Once you successfully logged in to the NMRFAM gateway (i.e. login1 or login2 computers) using putty you can connect to any computer (including spectrometers) using ssh. For example, if you want to connect to the 900 MHz spectrometer type in your putty window:
For other spectrometers use the table below:
computer short name
computer cow name
DMX Bruker 400
The first time that you login in a question about authenticity will appear. Answer yes.
The computer will respond with a request for your password. Type in your NMRFAM password.
Starting a VNC server (first time user, if not skip to vncserver command)
ssh -Y <username>@ login1.nmrfam.wisc.edu
paste the following into xstartup and then exit:
xsetroot -solid grey
#x-terminal-emulator -geometry 80×24+10+10 -ls -title “$VNCDESKTOP Desktop” &
Use the following commands (onÂ fleckviehÂ in this case):
vncserver -geometry 2048×1024 (you can adjust the geometry to fit your screen)
For xwinnmr (on DMX 400 (pisa) only) you MUST start the VNC server as:
vncserver -depth 8 -cc 3 -geometry 2048×1024
(chose a geometry close to the resolution of your monitor)
The computer will respond with something like:
New ‘fleckvieh:4 (username)’ desktop is fleckvieh:4
Remember the new desktop number (here it is 4)
exit (from fleckvieh)
exit (from login1)
Starting a VNC viewer
Download and extract SSVNC (for windows only). Create a desktop shortcut/icon for “sshvnc.bat” found in the ssvnc/windows installation folder and double click on it to start the program. A window will appear:
Enter fleckvieh:4 in the VNC Host:Display Name field.
Enter <username>@login1.nmrfam.wisc.edu in the the Proxy/Gateway field. (Alternatively, login2.nmrfam.wisc.edu can be used).
If you want to save what you just typed click on Save and name it for example fleckvieh. Next time you can use the Load button and the fields above will be pre-filled. If needed, you will change only the display number allocated to the vncserver.
In the black pop-up window type your NMRFAM password:
In the new pop-up window type your vncpasswd (the one that you entered when you started your first vnc session):
If you have forgotten the vncpasswd then ssh login1.nmrfam.wisc.edu and then ssh fleckvieh and type vncpasswd. You do not need to know the old vncpasswd to change it.
The vncviewer will provide you with a graphical desktop on the spectrometer computer. You can start vnmrj, topspin or xwinnmr from any shell (window) of that desktop:
Stopping a VNCserver
When you are finished accessing a NMRFAM computer via vnc, you can kill the vncserver by logging on to the computer that is running the vncserver and typing:
vncserver -kill :# where #n is the number of the vnc session that you want to kill