Abstract: A storage area network (SAN), which includes one or more remote systems, a plurality of storage devices, a SAN fabric comprising a plurality of fabric components for coupling the remote systems to the storage devices, and a central system having a SAN management server configured to monitor an amount of available storage in a file system used in the remote systems, and automatically provision additional storage to the file system in the event the amount of available storage in the file system decreases below a predetermined amount.

Abstract: Procedures and systems may be used for assigning data partitions to data-processing host computers, for example, to initially assign data partitions at the outset of a large data-processing job or during failover measures taken in response to a failed host in a share-nothing database management system (SN-DBMS). In one implementation, a method of managing exclusive access to a data partition within a database system assesses a first host and a second host that have exclusive access to a first and second data partition, respectively, within a database system. The method assigns exclusive access of the data partition to one of the first and second hosts based on factors that may include the processing powers of first and second the hosts, and on processing requirements (such as data quantity and data criticalness) for data on the first and second data partitions.

Abstract: Various methods and systems for securing access to hash-based storage systems are disclosed. One method involves receiving information to be stored in a storage system from a storage system client and then generating a key. The key identifies the information to be stored. The value of the key is dependent upon a secret value, which is associated with the storage system. The key is generated, at least in part, by applying a hash algorithm to the information to be stored. The key can then be returned the key to the storage system client. The storage system client can then use the key to retrieve the stored information.

Abstract: System and method for tracking statistics at the subfile level and transparently placing or migrating inactive or less active blocks of data to other storage devices. Embodiments may provide mechanisms to track statistics at the subfile level of files including, but not limited to, database files, and to transparently place or migrate inactive or less active blocks of data of the files from higher-performing, typically more expensive, storage to lower-performing, typically less expensive, storage, while placing or migrating active blocks of data of the files to higher-performing storage, based on the subfile-level statistics rather than on file-level timestamps. In some embodiments, knowledge of file structure (e.g., database file structure), for example knowledge of database partitions with header blocks and data blocks in databases using data partitioning, may be used to separate more active and less active blocks of data of files onto storage with different performance and/or other characteristics.

Abstract: One implementation of a method for providing backup storage services for encrypted data includes receiving signatures of convergently encrypted portions of data from client computers, determining whether the encrypted portions are already present on a backup storage, and obtaining only the needed portions. Users unassociated with a particular user account are denied access to information backed up in that account. The backup storage also stores password protected key files holding signatures of the unencrypted portions of data. One implementation of a system includes a memory, a single-instance storage circuit, a user account management circuit, and a signature index. The memory holds a user-account database and backup copies of convergently encrypted portions of data. The single-instance storage circuit uses the signature index to prevent duplicative backup copies. The user account management circuit responds to download requests after authenticating the user information associated with the requested data.

Abstract: A log manager may store a validation indicator with each data block of a log entry. The log manager may create a header block for each log entry that may include a validation indicator or tag. Such a validation indicator may be stored within the metadata for each data block. The validation indicator may additionally be stored in the metadata for the header block and it may be stored in header block itself. When recovering such a log, according to some embodiments, the validation indicators for each data block are checked against the validation indicator in the header block.

Abstract: Various methods and systems for performing cascaded replication are disclosed. For example, one method involves receiving an acknowledgment at a primary replication site from an intermediate replication site. The acknowledgment identifies whether a change has been applied to a remote replication site. The method also involves updating a journal, in response to the acknowledgment. The journal identifies whether the change is currently being replicated. The method can also involve detecting that the intermediate replication site is inaccessible. In response, the method synchronizes a copy of application data at the remote replication site by applying one or more changes identified in the journal to the copy of the application data at the remote replication site.

Abstract: Various methods and systems for automatically obtaining documents that are referenced by an electronic communication, such as an email or instant message, for archival are disclosed. One method involves searching at least a portion (e.g., the header and/or body) of an electronic communication for a reference to a document and, in response to detecting the reference, automatically obtaining an electronic copy of the document. The electronic copy of the document can then be archived.

Abstract: Systems, methods, apparatus and software can utilize a markup language to import and export data that is archived using a backup and restore system. An export utility extracts data produced or processed by an application program, converts it into a markup language format, and provides it to a backup and restore system. An import utility extracts data in a markup language format, converts it to another format, and provides the data for use by the application program. In one example, the application program is a database management system.

Abstract: Disclosed is a method implemented by a computer system that comprises a file system. The file system comprises first, second, third, and fourth directories wherein the first and second directories are sub-directories of the third directory, the third directory is a sub-directory of the fourth directory, the first directory stores only files identified by a first file extension, the second directory stores only files identified by a second file extension, and the first and second file extensions are distinct. In one embodiment, the method comprises receiving first and second requests to open first and second files, respectively, that are contained in the file system. The first and second requests comprise first and second file system paths, respectively. The first file system path comprises a first file name, and the first file name comprises the first file extension. The second file system path comprises a second file name, and the second file name comprises the second file extension.

Abstract: A method and apparatus for selectively storing data on a server. The method operates by accessing a computer file and defining a data block as a current block of data. The current block is subsequently checksummed using a rolling error identification code. The method then determines if the calculated checksum for the current block has been previously stored in a database. If a matching checksum for the data is found in the database, then a duplicate of the current block already exists and the process repeats by selecting a new block of data. Alternatively, if the calculated checksum is absent from the checksum and the process has advanced one block length, the process moves back one block length and stores the current block in an archive. Otherwise, the checksum advances one byte forward to form a new current block of data and the process repeats.

Abstract: In order to clustering documents, document vectors are formed for each of a plurality of documents of a corpus and plurality of reference vectors is generated. The document vectors are then compared to the reference vectors to generate similarity values for each of the document vectors. The document vectors are then sorted based on the similarity values for the document vectors to form a sorted list. Clusters are then formed based on the similarity between adjacent document vectors in the sorted list.

Abstract: A method, apparatus and computer-readable storage medium for ascertaining a set of preliminary characteristics of a first data structure and, responsive to determining that the set of preliminary characteristics matches a set of characteristics of a reference data structure, determining that a secondary characteristic of the first data structure indicates a replacement of the first data structure with the reference data structure is disclosed. Embodiments of the present invention further include replacing the first data structure with the reference data structure, in response to determining that the secondary characteristic of the first data structure indicates the replacement of the first data structure.

Abstract: A method and apparatus for controlling access to a storage area network among a group of hosts in a distributed computing environment. A host requests access to the storage area network by issuing an input/output request, and the input/output request is intercepted at the dynamic multipath (DMP) layer. The DMP layer checks the input/output request against an access control list. The DMP layer can grant or deny the input/output request from the host system. If the input/output request is granted, then the DMP layer passes on the input/output request to the HBA driver layer and the host is allowed to access the storage area network. If the request to access the storage area network is denied, the DMP management layer can initiate an appropriate response, such as a security procedure or generation of an error message alerting a user the request has been denied.

Abstract: A system and method for managing data storage. A computer system comprises a data storage application and an API. The API presents a logical storage model to the data storage application for storing data on one or more storage appliances and accepts first and second plugins coupling first and second storage appliances, respectively, to the API. The first and second storage appliances store data according to different physical storage models. The API receives an access request from the data storage application targeting a portion of the logical storage model. In response to the access request, the API identifies a plugin and a corresponding storage appliance associated with the portion of the logical storage model and utilizes the identified plugin to map the portion of the logical storage model to a corresponding portion of the selected storage appliance's physical storage model.

Abstract: A method includes assigning a port identifier to a first port on a node and communicating data on a first path between the first port and a logical unit on an active/passive storage array. The port identifier is registered in a persistent reservation scheme for the logical unit. The method also includes detecting a failure of the first path, de-assigning the port identifier from the first port, assigning the port identifier to a second port on the first node, and resuming communications between the node and the logical unit. One implementation of a system includes a first port configured to communicate with a storage device, a second port configured to communicate with the storage device, and an identifier management block. The identifier management block executes a failover with N_Port ID Virtualization commands that transfer a world wide port name from the first port to the second port.

Abstract: A system and method for efficiently accessing replicas of a storage object. A first node may perform a find operation to determine a plurality of nodes that each store a replica of a first storage object. For each node in the plurality of nodes, the first node may establish a direct connection to the node. The first node may then access the replicas of the first storage object using the respective direct connections to the plurality of nodes. In one embodiment, the nodes may be nodes in a peer-to-peer network. Establishing a direct connection to each storage object replica may enable the first node to communicate with each node in a single hop without having to pass messages via intermediate nodes in the peer-to-peer network.

Abstract: A method and apparatus for logging write requests to a storage volume in a network data switch is described. In one example, a switch component in a switch receives a write request from a host server. The write request is associated with a destination in the storage volume. A logging element is identified that is associated with the destination of the write request. The logging element may be a switch component in the switch (e.g., a virtualization card), or may be dedicated logging circuitry in the switch. The identified logging element then logs a write intent for the destination in a log.

Abstract: A method, system, computer system, and computer program product to quickly synchronize replicas of data stored at multiple secondary nodes upon failure of a primary node. Secondary nodes to which an update to data in a region of a storage area is sent are identified. When all of the secondary nodes have acknowledged the update, a notification is sent to each of the secondary nodes. Respective indicator(s) (e.g., “outstanding update” or “out of sync” indicators) can be set to indicate that the data have changed in respective region(s) at one of the secondary nodes when the update has been received at that secondary node. The indicator(s) can be reset for the respective region(s) when the notification sent by the primary node is received at the secondary node. Data in the region(s) can be synchronized with data at secondary nodes when either node has an indicator set for that region.

Abstract: A method is proposed. The method includes receiving a file operation request from a process and performing a census of instances of a file applicable to the file operation request to populate a data structure. The data structure including a listing of the instances of the file applicable to the file operation request. The data structure also includes characteristics for a first instance from among the instances of the file applicable to the file operation request, and characteristics for a second instance of a selected file from among the instances of the file applicable to the file operation request. The method also includes eliminating the first instance from among the instances of the file applicable to the file operation request on the basis of a rule associated with properties from a record for the process, and the characteristics for the first instance.