Abstract: A system is provided to improve storage server performance. The system comprises a receiving component of a storage server to receive a partner server's file system metadata while the partner server operates in a normal mode. The partner server's file system metadata is stored in the storage servers metadata cache and is used to mount the partner server's file system when the first server transitions into a takeover mode of operation.

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 reliable peer-to-peer communication is provided. The system and method includes a cluster connection manager that acts as a unified resource for opening, closing and maintaining peer-to-peer communication channels between applications executing on storage systems comprising a storage system cluster. The cluster connection manager communicates with cluster connection manager clients to maintain and manage the communication channels. The cluster connection manager may also be operatively interconnected with a plurality of cluster interconnect devices, thereby enabling failover operation in the event that a cluster interconnect device suffers an error condition.

Abstract: A filer converts a traditional volume to a flexible volume by: creating an aggregate on storage devices other than the storage devices of the traditional volume; on the aggregate, creating a flexible volume large enough to store metadata describing files residing on the traditional volume; on the flexible volume, creating metadata structures that describe the files of the traditional volume, except that the metadata indicates that data blocks and indirect blocks are absent and must be fetched from another location. As the filer handles I/O requests directed to the flexible volume, the filer calculates physical volume block number (PVBN) addresses where the requested blocks would be located in the aggregate and replaces the absent pointers with the calculated addresses. After the absent pointers have been replaced, the filer adds the storage devices of the traditional volume.

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 clustered storage server detects an offline condition in another storage server in the cluster and executes a cluster takeover procedure which includes taking control of the storage system associated with the offline storage server, and merging a local control-of-service policy with a control-of-service policy associated with the offline storage server.

Abstract: A method for managing a cluster of file servers is disclosed. The method has the first step of writing coordinating information for a plurality of servers of the cluster of servers to a master mailbox record, the master mailbox record written to a specific location on each disk of a set of lock disks, the set of lock disks having a plurality of disks, the plurality of disks chosen so that in the event of failure of a server of the plurality of servers, at least one lock disk will be available to the remaining servers. The method has the second step of writing a second copy of eth coordinating information to the master mailbox record of the set of lock disks.

Abstract: A method and an apparatus to perform fast log replay have been disclosed. In one embodiment, the method includes preloading a buffer with data based on a catalog in response to a failure of a storage server and replaying a log as the buffer is being preloaded, wherein replaying the log comprises re-executing a set of modifying operations previously logged in a local non-volatile storage device in the storage server using the data preloaded.

Abstract: A system and method for disk ownership in a network storage system. Each disk has two ownership attributes set to show that a particular file server owns the disk. In a preferred embodiment the first ownership attribute is the serial number of the file server being written to a specific location on each disk and the second ownership attribute is setting a SCSI-3 persistent reservation. In a system utilizing this disk ownership method, multiple file servers can read data from a given disk, but only the file server that owns a particular disk can write data to the disk.

Abstract: A method and system for efficiently accessing a pool of mass storage devices are described. In one embodiment of the invention, a primary storage server and a secondary storage server share a pool of mass storage devices. The secondary storage server is configured to provide read-only access to the storage pool of mass storage devices, while the primary storage server is configured to provide read and write access to the pool of mass storage devices.

Abstract: A system and method for reliable peer-to-peer communication is provided. The system and method includes a cluster connection manager that acts as a unified resource for opening, closing and maintaining peer-to-peer communication channels between applications executing on storage systems comprising a storage system cluster. The cluster connection manager communicates with cluster connection manager clients to maintain and manage the communication channels. The cluster connection manager may also be operatively interconnected with a plurality of cluster interconnect devices, thereby enabling failover operation in the event that a cluster interconnect device suffers an error condition.

Abstract: A method and apparatus for geographic specific search results in response to a search request having an address field includes retrieving map portion having the address thereon. The method and system further includes determining entities in geographic relation to the address and generating an entity listing, where the entity listing includes listing of the various entities. These entities may represent any type of business, club, library, government building/office, or other locations. The method and apparatus further includes determining various descriptive terms that relate to the entities which are in geographic relation to the address. These terms include hyperlinks to corresponding entity listings. The method and apparatus further includes generating a visual display that includes: the map portion with the address displayed thereon; an entity portion that includes the entity listing; and a term portion with a taxonomical display of the plurality of terms.

Abstract: A system and method to perform discretization and cardinality reduction of item attributes using collaborative filtering techniques are described. Data input by a user is received over a network, the input data further including a plurality of items and associated item metadata related to events performed by the user. The input data is further processed to obtain a predetermined number of groupings, each grouping having a calculated value based on a distance parameter between corresponding attributes of each item stored within the item metadata. Finally, a similarity parameter is computed between each pair of items within the plurality of items based on associated groupings and recommendations of the items are presented to the user based on the corresponding calculated similarity parameter.

Abstract: A system and method to compute attribute-based similarity between items using collaborative filtering techniques are described. Events input by a user over a network are received, the events further including a plurality of items and associated item metadata. A similarity value is further computed between each pair of items within the plurality of stems based on corresponding attributes of each item stored within the item metadata. Finally, recommendations of the items to the user are presented based on the corresponding calculated similarity value.

Abstract: Data storage methods and apparatus combining read-only and read-write storage are described. Data may be located by information maintained in a filesystem; each data block is stored in either the read-only storage or the read-write storage.

Abstract: A data storage system has two computers. Each computer is assigned to a set of data. Two copies of each set of data are maintained. A first copy is stored on a first set of disks and a second copy is stored on a second set of disks. Each time that a data is written by a computer, a label is written to each set of disks, the label having fields for a status of each computer, a first ordinal which is increased each time that a new data is written, and a time stamp giving a time at which the last write was performed. After failure of a computer, a processor determines, in response to reading the labels of the first set of disks and the second set of disks, the most up to date copy of the data assigned to the failed computer.

Abstract: A system and method are disclosed for transferring a behavior profile anonymously across multiple domains. The behavior profile may be established from a first domain, but transferred anonymously such that it is accessible by other domains. The behavior profile may be used for generating targeted advertisements.

Abstract: A method and an apparatus to perform fast log replay have been disclosed. In one embodiment, the method includes preloading a buffer with data based on a catalog in response to a failure of a storage server and replaying a log as the buffer is being preloaded, wherein replaying the log comprises re-executing a set of modifying operations previously logged in a local non-volatile storage device in the storage server using the data preloaded.

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.