Patent ID: 7653699

Claim:
A system comprising: one or more server computer systems, wherein each of the one or more server computer systems comprises a respective processor and a respective memory; and one or more nonvolatile storage devices, wherein the one or more nonvolatile storage devices store a plurality of physical file systems which are hosted by the one or more server computer systems; wherein the plurality of physical file systems are accessible through a virtual file system having a namespace, wherein the virtual file system includes metadata which are partitioned across the plurality of physical file systems, wherein a respective partition of the metadata of the virtual file system is stored on each of the one or more nonvolatile storage devices; wherein the one or more server computer systems are configured to: independently perform a file system consistency check on each of the physical file systems to independently validate each partition of the metadata; determine a plurality of links between the physical file systems by determining a plurality of shadow file identifiers, wherein each of the shadow file identifiers comprises a placeholder in a respective one of the physical file systems for a remote file stored in a respective different one of the physical file systems; and perform a file system consistency check to validate metadata comprising the links between the physical file systems.