Cluster means different things to different people. In the context of this article, cluster is best defined as scale-out — scale-out clusters generally have a lot of the same type of components like Web farms, render farms, and high performance computing (HPC) systems. Administrators will tell you that with scale-out clusters any change, no matter how small, must be repeated up to hundreds of thousands of times; the laziest of admins have mastered techniques of scale-out management so that regardless of the number of nodes, the effort is the same. In this article, the authors peer into the minds of the laziest Linux® admins on Earth and divulge their secrets.
Since their first appearance in 1998 in the list of the Top 500 fastest computers in the world, Linux clusters have risen from an obscure science experiment to the position of today’s dominant force in supercomputing technology. In fact, the number of Linux clusters in the Top 500 list has grown from 1 system in 1998 (1 cluster, 1 Linux OS system) to four-fifths of the list in 2008 (400 clusters, 458 Linux OS systems).