Buzzwords are as common in the Linux world as they are in the realm of proprietary software. This truism is certainly highlighted by the recent popularity of such terms of "thin versus fat," "scaling up versus scaling out;" and "consolidation versus clustering."
Clustering itself is a buzzword that is popular in all aspects of IT--it is not something that is native to Linux, though Linux is being adopted for clustering use at a very fast pace. That is mainly because Linux is ideally suited for multi-server parallel processing, usually right out of the box. Couple that with Linux's affordable licensing fees (read: little to none), and you have a strong recipe for success.
Clustering is usually used for one or two specific computational needs: high performance and high availability. It is important to make this distinction early on, because clustering may not be the universal elixer that it is often made out to be.
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