Patent ID: 7380158

Claim:
An apparatus for serving a file system request of a client from a network comprising: a file server for processing the file system request, the file server includes functional units, the functional units each perform an associated function and are separated by the function they perform, the functional units able to send messages to each other, the functional units include a request manager, an inode manager, a disk manager, and a cache controller; permanent storage in which at least a portion of the request is stored, the permanent storage includes a disk array, the file server sends an acknowledgement to the client through the network that the portion of the request that has been received by the file server from the network has been stored but before the request has been stored in the disk array; nonvolatile memory in which the portion of the request is stored until the portion can be stored in permanent storage, the nonvolatile memory includes nonvolatile RAM; a first power source for providing electricity to the disk array, the nonvolatile RAM and the file server, the first power source in electrical communication with the disk array, the nonvolatile RAM and the file server; and a second power source that provides electricity only to the nonvolatile RAM when the first power source fails, the second power source in electrical communication with the nonvolatile RAM, the second power source includes batteries.