Clustering vs. Fault-Tolerant Servers

mstansberry writes "According to SearchDataCenter.com fault-tolerant server vendors say the majority of hardware and software makers have pushed clustering as a high-availability option because it sells more hardware and software licenses. Fault-tolerant servers pack redundant components such as power supply and storage into a single box, while clustering involves the networking of multiple, standard servers used as failover machines." Perhaps some readers on the front lines can shed a bit more light on the debate based on both proprietary and Linux-based approaches.