Abstract: In a method for operating a data storage system, a request is issued that an ownership attribute of a logical arrangement of storage space associated with a first storage system be associated with a second storage system. In response to the request, the ownership attribute is changed to a state of unowned. In response to the request, and in response to the state of unowned, the ownership attribute of the logical arrangement of storage space is changed to a new set of attributes associated with the second storage system to change ownership of the logical arrangement of storage space from the first storage system to the second storage system.

Abstract: A system and method for determining a disk ownership model to be utilized by a storage system is disclosed. The storage system and method determines the individual disk ownership of each accessible disk to the storage system. If the number of disks utilizing a first ownership model is exceeded, the storage system utilizes the first ownership model. Otherwise, the storage system utilizes a second ownership model.

Abstract: A system and method for associating a network address with a volume, individual disk or collection of disks in a network storage system. Identifying information is stored on each volume or disk so that a file server can map a network address to a MAC address associated with a particular network interface controller of a file server. Input/output operations directed to the network address associated with a particular volume or disk is directed to the file server that is currently managing that volume or disk. In a system utilizing these address associated volumes, the name and address of data does not change as different file servers manage a particular volume or disk.

Abstract: A system and method for a file server to allocate spare disks in a network storage system. The method determines the available spare disks and first selects those disks that satisfy one or more required rules. The method sorts the spare disks by a set of ordered policies to determine a highest-ranked disk that is then selected as the spare to be utilized. If multiple disks are equally ranked, one of the equally ranked disks is randomly chosen to be the spare disk allocated.

Abstract: A system and method for transferring ownership of a volume in a networked storage environment. The method first moves the disks that comprise the volume being transferred from a source-owned state to an un-owned state. Next the disks are moved to a destination-owned state. Each step of the transfer process completes on all disks before the next step begins to ensure consistency and disks that have conflicting owners. Alternate embodiments include logging by the source and destination nodes to permit a resumption of the transfer if one node becomes inactive during the transfer.

Abstract: A system and method for determining a disk ownership model to be utilized by a storage system is disclosed. The storage system and method determines the individual disk ownership of each accessible disk to the storage system. If the number of disks utilizing a first ownership model is exceeded, the storage system utilizes the first ownership model. Otherwise, the storage system utilizes a second ownership model.

Abstract: A system and method for a file server to allocate spare disks in a network storage system. The method determines the available spare disks and first selects those disks that satisfy one or more required rules. The method sorts the spare disks by a set of ordered policies to determine a highest-ranked disk that is then selected as the spare to be utilized. If multiple disks are equally ranked, one of the equally ranked disks is randomly chosen to be the spare disk allocated.

Abstract: The invention is a method for operating a file server system in a cluster mode that provides for relatively rapid and reliable takeover by one file server of another. This is done by a system operator requesting takeover of file services of a file server, letting the first file server complete existing file service requests from clients, refusing further file service requests addressed to the first file server, and the one file server taking over by transferring file service requests to the one file server. As part of this takeover the one file server takes on the identity of the first filer and activates network interfaces and network addresses that replicate the first server's network addresses.

Abstract: The invention is a method for operating a file server system in a cluster mode that provides for relatively rapid and reliable takeover of a failed file server in the cluster by a partner file server when the failed file server has detected a fault that will cause it to shut down. This is done by the failed file server requesting the one file server to take over its file services after detecting the fault in its operations, the one file server letting the failed file server complete existing file service requests from clients, refusing further file service requests addressed to the failed file server, and the one file server taking over by transferring file service requests to the one file server. As part of this takeover the one file server takes on the identity of the failed filer and activates network interfaces and network addresses that replicate the failed server's network addresses.

Abstract: The invention provides a method and system in which a node in a 2-node high availability cluster can declare itself impaired. In doing so, an impaired node can self diagnose or request another node in the cluster assist in diagnosing the problem. An impaired node can then request another node takeover the impaired node's tasks whereby the impaired node is able to shut down gracefully.

Abstract: A global mount mechanism capable of maintaining a consistent global name space in a distributed computing system including a plurality of nodes interconnected by a communications link is herein disclosed. The global mount mechanism mounts a new file system resource into the global name space in a coherent manner such that the new file system resource is mounted at the same mount point concurrently in each node. The global mount mechanism accommodates mount or unmount requests initiated from a requesting node for a resource located in a remote node. The global mount mechanism is also used to unmount a file system resource from the global name space. The global mount mechanism also includes an initialization procedure that is used to generate the global name space initially by providing each local mount point with a global locking capability.