To install xdmx just follow these instructions.
sudo apt-get install xdmx
Which will install xdmx and any other packages on which it depends.
|Maintainer||Debian X Strike Force <email@example.com>|
|Description||distributed multihead X server display device(s). It provides multi-head X functionality for displays that might be located on different machines. Xdmx functions as a front-end X server that acts as a proxy to a set of back-end X servers. All of the visible rendering is passed to the back-end X servers. Clients connect to the Xdmx front-end, and everything appears as it would in a regular multi-head configuration. If Xinerama is enabled (e.g., with +xinerama on the command line), the clients see a single large screen.|