Accessing the CDS using X-Windows
A number of important component facilities within the CDS require
X-Windows to be installed on your workstation.
For instance, you
need X-Windows to access the Cambridge crystallography database via
ConQuest (and associated components) and also to use the PeakQuest
powder diffraction system.
To use the components mentioned above you need to logon with your
username to the main CDS server (cds.dl.ac.uk) using
"secure shell" mechanisms.
- Unix/Linux machines and Macs running OSX will normally have
X-Windows (X11) and related "Server" software pre-installed
You can use the ssh command to gain secure shell access to the
CDS server or sftp for file transfer
Windows PCs are only able to support an X-Windows session if an
X-Server emulator is installed (see section below)
You may also need to install extra software to make the secure shell
Our recommendation for configuring your X-Windows system is to use
"X11 forwarding". Details are give on our Secure Shell
However, if that option is not available to you scroll to the end of
this page for details of alternative methods.
As indicated above Unix/Linux and Mac OSX should come with X11 already
If you have a Mac OSX system without X11 it is available for download from
[eXodus is an option for older Macs (OS8 or 9)].
Our current recommendations for Windows PCs are Exceed (where you have
an HEI site licence) or Xming (free software) - see below.
Cygwin/X, MI/X, WinaXe and X-Win32 should also be considered if site
a licence for Exceed is not available or where cost is a problem.
Open Text Exceed
This was previously known as Hummingbird Exceed (before that Vista Exceed).
Recent versions add the option of Secure Shell logins and X11 forwarding.
Available to HEI sites as a CHEST
is a freely available X Window Server for Microsoft Windows (XP/2003/Vista/7).
Users should download the Xming-mesa version.
More information about Xming and setting it up is
For Macintosh PowerPC, G3, G4 or iMac .
EXodus is now available from Powerlan-USA. Now contains TunnelMate 1.0.1 Secure Shell client but only for Mac OS X.
The current version is 8.0.2.
An evaluation copy can be requested from
The CHEST deal has expired but copies can be purchased for $135.
For Windows 95/98/NT4/2000/ME/XP Operating Systems.
Cygwin/X is a port of XFree86 to the Microsoft Windows family of operating systems and is available free of charge (licensed under an Open Source compliant license).
Cygwin/X consists of an X Server, X libraries, and nearly all of the standard X clients, such as xterm and xhost.
A copy can be downloaded from the
Cygwin site where a user
guide is also available (make sure you select the 'xorg-x11-base'
package from the 'X11' category).
X server available from
for Windows XP/NT/2000/95/98/ME. 15 day evaluation.
$19.99 for 1 year or $49.99 for non-expiring license.
For Windows PCs.
Version 5.3 includes SSH and OpenGL support. A 1 month license key can be obtained from
which will enable you to evaluate X-Win32 in fully-licensed mode.
After 30 days, the program will revert to a 2-hour demo mode.
Full (academic) version cost $115, though other academic deals are
WinaXe Plus (formally X-WinPro)
For Windows PCs.
A free evaluation version is available from
Labtam Finland Ltd.
- operational 30 minutes per run. After 30 minutes session
you need to restart WinaXe. No reinstallation needed. Priced at $90 or
$100 for Plus version which includes SSH client.
for Windows is a available at $25
(free 15 day trial) from
For any Power Macintosh or Power Macintosh
Compatible with older versions of the Macintosh Operating System
7.5 to 9.0.4. 16 MB of RAM are recommended.
A Secure Shell for XTen 6.1 package is available for download - SSH is
freely distributed for non-commercial and private use only.
version is available for download from
Priced at $175.
Making the connection without X11 forwarding
We recommend that you use X11 forwarding where possible.
However, if this not the case there are additional commands required
to establish a link with an X-Server or emulator.
When X11 forwarding is not used the CDS server (cds.dl.ac.uk) needs to
be told the address of your workstation so it can transmit data traffic
relating to your X-Windows session. The command to type on connecting
to the CDS server is:
setenv DISPLAY [IP]:0
setenv DISPLAY [IP]:0;xterm -ls -sb
where [IP] represents the Internet address of your workstation
- xterm is used if you wish to set up a new X-terminal window
- add -sb if you want scroll bars on the X-terminal
You may need to enter "xhost cds.dl.ac.uk" before connecting from your
workstation (this gives permission to receive traffic from the CDS
It may make sense to seek recommendations from your local computer
support people when setting up X-server emulators such as Exceed. Also
feel free to contact the CDS (email@example.com)