In addition to the considerations for High Availability clusters, more tightly coupled environments such as Beowulf clusters also require an infrastructure to manage and distribute computing tasks. There are several web pages devoted to creating a Beowulf cluster using Debian as well as packages that aid in creating such a cluster. One such page is https: / /wiki. debian. org/StartaBeowulf, a Debian Wiki page on Beowulf basics. The manual for FAI, mentioned previously in configuration management, also has a section on creating a Beowulf cluster. Books are available as well. Debian provides several packages that are helpful in building such a cluster, such as the OpenMPI libraries for message passing, and various utilities that run commands on multiple systems, such as those in the kadif package. There are even projects that have released scripts and live CDs that allow you to set up a cluster quickly (one such project is the PelicanHPC project, developed for Debian Lenny, hosted at http://www .pelicanhpc. org/.
This type of cluster is not something that you can set up and go. Beowulf and other tightly coupled clusters are intended for highly parallel computing, and the programs that do the actual computing must be designed specifically for such an environment. That said, some packages for specific parallel computations do exist in Debian, such as nwchem, which provides several applications for computational chemistry that take advantage of parallelism.
