What is a cluster?

[easg]

Can someone explain me what is a cluster?

[wedor]

Generally a group of servers that perform the same function, the idea is to have maximum uptime by having multiple servers to balance the load or in case one fails.

[ZeratulsAvenger]

Connecting two or more computers together in such a way that they behave like a single computer. Clustering is used for parallel processing, load balancing and fault tolerance. Clustering is a popular strategy for implementing parallel processing applications because it enables companies to leverage the investment already made in PCs and workstations. In addition, it's relatively easy to add new CPUs simply by adding a new PC to the network. Microsoft's clustering solution for Windows NT systems is called MSCS.

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