Traditional distributed file systems can't provide cluster system with strict single-system image (SSI), which make it difficult to manage file system in a way.

传统的分布式文件系统无法为集群系统提供严格的单一映像功能(SSI)，使得集群系统的管理较为复杂。

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Created in 2002 openMosix was a free cluster management system that provided single-system image (SSI) capabilities, e.g. automatic work distribution among nodes.

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