Resources

Connecting Remotely

• Machines names for nx client and ssh access.
• ssh and X11
• nxclient
• X-Win 32
• Cygwin

Machines names for nx client and ssh access.

The hostnames for logging into the EE computers via ssh or NX are listed below:

VLSI Lab (1218 Mudd) - vlsi1.cisl.columbia.edu - vlsi18.cisl.columbia.edu

ILAB Lab (1235 Mudd) - micro1.ilab.columbia.edu - micro17.ilab.columbia.edu

1227 Mudd Host names - circuit1.cisl.columbia.edu - circuit12.cisl.columbia.edu

ssh and X11

The design of the X Protocol specifies a client-server relationship between an application and its display. In X, the software that manages a single screen, keyboard and mouse is known as an X server.

A client is an application that displays on the X server and is usually termed an X client or simply the application. The X client sends requests to the X server, for example a drawing or information request. The X server accepts requests from multiple clients and returns to the X client replies for information requests, user input and errors.

nxclient

Compressed X11 Sessions Using Nomachine's SSH client and server

We are pleased to announce that the EE department will begin offering a new remote access technology for the cisl and ilab hosts in 1218 and 1235 Mudd, or more commonly known as the ILAB and VLSI computer labs. The new technology provides the following advantages over the existing X11 mechanisms that we have been using up until this point.

1. Faster and more responsive X11 GUI. The Nomachine client and server are able to accomplish this by selectively caching elements of the screen that do not change, heavily compressing screen attributes that do need to be refreshed and sending requests and updates in a bulk fashion between the client and server.

2. Users can suspend their sessions and resume them at a later date. This means that students can keep their Cadence sessions open on the nxserver and resume them from where they left off.

3. Windows clients no longer need to install Cygwin or xceed in order to use Cadence on their Windows desktops. Instead students install a small binary client application which takes a fraction of the time that Cygwin takes to install.

4. Full gnome session automatically. This means that when logging into the nxserver students don't have to start up xclients individually, they will get a complete gnome session.
   
   

Nxclient Configuration

1. APPLY FOR AN ILAB/VLSI ACCOUNT - To set this up, first you must already have an EE account for the machines in 1218 and 1235 Mudd. If you do not have an ILAB or VLSI lab account, please email me at with your uni and the EE class that you are a member of.
   

2. DOWNLOAD AND INSTALL THE NOMACHINE CLIENT AND FONTS - Go to http://www.nomachine.com/download.php, download and install the client and the fonts that are appropriate for your platform. The fonts can be downloaded from the add-on section right below the nxclient download on the the nxclient download page. The font downloads are labeled nxfonts-xxx. If you do not install the fonts for a Windows installation, Cadence will not run because it does not have the fonts that it needs to start up. You will see an error that says "X Error of failed request: BadName (named color or font does not exist)" if you have not installed the correct fonts. The Windows client is incompatabile with some versions of Cygwin, so you should make sure that your Cygwin version is compatabile before proceeding. You can read this post if you would like to learn about Cygwin compatability. http://www.nomachine.com/ar/view.php?ar_id=AR12B00117
   
   
3. DOWNLOAD AND CONFIGURE THE CLIENT KEYS - Using WinScp or scp download the ilab.key file from the home directory of your ilab or vlsi account to your desktop. Then, either type /usr/bin/nxclient --wizard from a linux host or go to start -> run -> NX connection wizard in Windows. When the wizard prompts you to enter the name of a host, enter one of names of the hosts outlined in ilab-hosts file in your home directory Keep the port set to 22. Name the session whatever you like.
   
   
4. CONFIGURE NXCLIENT SETTINGS - After finishing the wizard you will see the logon dialog. Click on the button that is labelled Configure... Under the Advanced tab, check the Enable SSL encryption box in the network section. Under the General Tab, under Desktop, make sure that you are using UNIX and GNOME for your settings and for now set the Display screen area to 800x600. I have had better luck resuming sessions on different machines if I set the screen area to a lower value. Click on the key... button. Highlight the existing key and delete it within the text box. Click import and ilab.key file that you just downloaded to your desktop. Click Save until you are back at the logon menu. Enter the user name and password that you normally use to log on to the 1218 and 1235 machines and click login. You should get a new X session.
   To suspend the session, click on the X on the upper right hand corner of the window and select suspend, when it prompts you to terminate or suspend your session.
   
   
5. DISCLAIMER - Please be very careful while using this software. Some parts of it are still unpolished and cause sessions to hang and become unrecoverable from a suspend. In other words save your work often and don't depend on the suspend feature. Please use it to complement your other remote access methods such as x-win32 and cygwin.
   
   For more information concerning gui remote access methods consult please consult the following document.
   
   http://www.ee.columbia.edu/index.php?dir=systems&page=x11
   
   For more information concerning nx please consult the following documents
   
   http://www.nomachine.com/usage.php
   
   and
   
   http://fedoranews.org/contributors/rick_stout/freenx/
   
   Thanks,
   
   Bill McCabe
   EE Systems
   
   
   

X-Win 32

X-Win 32

You may already have a commercial software package called X-Win 32 on your computer that permits the EE servers to display graphics over a remote connection. If this is the case, launchX-Win 32, right click on the system tray icon, and start the X-Config tool. When setting upa new SSH session with the tool, specify /usr/X11R6/bin/xterm -ls as the command to run. When you restart X-Win 32, it should automatically start up a terminal session on the remote server from within which you can run remote applications.

Cygwin