Abstract: One aspect is directed to a method for performing data migration from a first volume to a second volume while allowing a write operation to be performed on the first volume during the act of migrating. Another aspect is a method and apparatus that stores, in a persistent manner, state information indicating a portion of the first volume successfully copied to the second volume. Another aspect is a method and apparatus for migrating data from a first volume to a second volume, and resuming, after an interruption of the migration, copying data from the first volume to the second volume without starting from the beginning of the data. Another aspect is a method and apparatus for migrating to data from a first to a second volume, receiving an access request directed to the first volume from an application that stores data on the first volume, and redirecting the access request to the second volume without having to reconfigure the application that accesses data on the first volume.

Abstract: A data storage system includes methods and apparatus that provide volumes for access by host computing devices. The volumes can have a storage size that is independently configurable from an actual amount of data storage that may or may not be associated with the volume. The volumes also have a persistent identifier. The volumes can have any amount of associated storage space allocated to the volume, including none, within the data storage system. Since the storage size and associated storage space are each independently configurable from each other, host that interface with the data storage system can perceive the volumes as being larger than they really are. A dynamic volume configuration technique is provided which allows storage space within storage devices in the data storage system to be dynamically associated and disassociated (i.e., added and removed) from the volumes on an as-needed basis, without requiring disruption of host activities with respect to the volumes.

Abstract: A registration application that allows a service provider customer that is using data storage resources (storage and/or storage-related services) provided by the service provider to register with a Service Provider Management System (SPMS) that is maintained by the service provider. The registration application executes on each of the customer's servers (that is, those which are connected to resources being used) to produce registration information and provides that registration information to the SPMS. The resources have a scratch pad storage area that is used by the servers and the SPMS to communicate with each other. The registration information is passed to the SPMS by the servers indirectly via the scratch pad area. The SPMS uses the registration information to associate customer information with the resources used by that customer's servers. The association of the customer information and resources can then be used by the SPMS to track customer usage of the resources for billing and other applications.

Abstract: One aspect is directed to a method for storing, in a persistent manner, a state of the storage process such that the state of the storage operation may be recovered if the storage operation is interrupted. Another aspect is directed to a method and apparatus that stores the state of a storage operation in a non-volatile memory of a computer that stores data on a storage system. Another aspect is directed to a method for recovering the state of the storage process without having to re-perform storage operations. Another aspect is directed to maintaining state information for other purposes such as monitoring access to data storage locations.

Abstract: One embodiment is directed to a method in a computer system including a host computer and at least one storage system including first and second storage volumes, the host computer including at least one application program executing thereon. The method comprises acts of intercepting and redirecting an access request from the at least one application program to the first storage volume to the second storage volume. Other embodiments are directed to a computer readable medium with instructions for performing the method, a host computer with at least one controller to intercept and redirect the access request. Other aspects are directed to methods in a computer system including a host computer, a first storage system including a first storage volume, and a second storage system including a second storage volume, wherein the second storage volume is a hardware mirror of the first storage volume.

Abstract: A storage system is provided that includes a plurality of storage devices and a data structure, accessible to the storage system, that includes a plurality of records corresponding to a plurality of network devices that are coupled to the storage system. Each record includes configuration data that identifies each of the plurality of storage devices to which data access by a respective one of the plurality of network devices is authorized. Each record may further include visibility data that identifies whether certain types of non-data access, such as requests for general information relating to a respective storage device, by a respective one of the plurality of network devices is permitted, even though data access to the respective storage device by the respective one of the plurality of network devices is not authorized.

Abstract: Methods and apparatus for migrating a logical object. In one embodiment, a migration is performed by automatically determining the source location(s) of the logical object, moving the data stored therein to a target location while maintaining the availability of the data at the source location to an application program, and automatically servicing access requests from the application program at the target location after moving the data. In another embodiment, a migration is performed by automatically provisioning target location(s) to store a logical object, moving the data in the logical object to the target location(s) while maintaining its availability to an application program, and automatically servicing access requests from the application program at the target location after moving the data.

Abstract: A data storage system includes methods and apparatus that provide volumes for access by host computing devices. The volumes can have a storage size that is independently configurable from an actual amount of data storage that may or may not be associated with the volume. The volumes also have a persistent identifier. The volumes can have any amount of associated storage space allocated to the volume, including none, within the data storage system. Since the storage size and associated storage space are each independently configurable from each other, host that interface with the data storage system can perceive the volumes as being larger than they really are. A dynamic volume configuration technique is provided which allows storage space within storage devices in the data storage system to be dynamically associated and disassociated (i.e., added and removed) from the volumes on an as-needed basis, without requiring disruption of host activities with respect to the volumes.

Abstract: Methods and apparatus for migrating a logical object. In one embodiment, a migration is performed by automatically determining the source location(s) of the logical object, moving the data stored therein to a target location while maintaining the availability of the data at the source location to an application program, and automatically servicing access requests from the application program at the target location after moving the data. In another embodiment, a migration is performed by automatically provisioning target location(s) to store a logical object, moving the data in the logical object to the target location(s) while maintaining its availability to an application program, and automatically servicing access requests from the application program at the target location after moving the data.

Abstract: A method and apparatus for a networked computer system including a plurality of devices and a shared resource. In response to one of the devices attempting to access the shared resource and representing itself to the shared resource as a first device, determining whether the device is attempting to access the shared resource through a physical connection through the network that is different than a physical connection used by the first device to access the shared resource, and when it is, denying the attempted access.

Abstract: Detecting computer viruses includes providing a disk space having at least a portion that is partitioned into separate segments, each segment being accessed by at least one of a plurality of hosts. A first one of the segments is accessed using a different file system than a second one of the segments. An antivirus unit scans at least part of the disk space for viruses. The part of the disk space that is scanned by the antivirus unit includes at least some parts of the first and second segments. The first and second segments may correspond to different physical portions of the disk space. The first and second segments may or may not overlap. The first and second segments may correspond to logical entities. Part of the disk space that is scanned by the antivirus unit may correspond to particular types of files stored in the disk space. The disk space that is scanned by the antivirus unit may correspond to files that have been modified since a previous virus scan.

Abstract: A storage system is provided that includes a plurality of storage devices and a data structure, accessible to the storage system, that includes a plurality of records corresponding to a plurality of network devices that are coupled to the storage system. Each record includes configuration data that identifies each of the plurality of storage devices to which data access by a respective one of the plurality of network devices is authorized. Each record may further include visibility data that identifies whether certain types of non-data access, such as requests for general information relating to a respective storage device, by a respective one of the plurality of network devices is permitted, even though data access to the respective storage device by the respective one of the plurality of network devices is not authorized.

Abstract: A method and apparatus for manipulating data in a storage device that is coupled to a host computer. Manipulations that can be performed by the storage device include moving non-contiguous blocks of data between the host computer and the storage device in a single operation. Other manipulations can be performed directly by the storage device without passing data to or from the host computer and include copying data from one logical object that is defined on the host computer to another, initializing, backing-up, transforming, or securely deleting a logical object that is defined by the host computer with a single command. In one embodiment, an application programming interface is provided that allows a relationship between logical objects on a host computer and storage locations on a storage device to be communicated between the host computer and the storage device.

Abstract: An object is authenticated by transmitting a random number to the object. The object has an integrated circuit chip including a memory and encryption circuitry. The memory stores information defining an encryption scheme preassigned to the object. The encryption circuitry reads the memory, and encrypts the random number according to the encryption scheme defined by the information read from the memory to produce encrypted data. The memory cannot be read from any output of the integrated chip, and the chip is constructed so that it is virtually impossible to recover the information contained in the memory by visual inspection, probing, or disassembly of the chip. The object is authenticated by checking whether the encrypted data is a correct result of encrypting the data using the encryption scheme pressigned to the object.

Abstract: Methods and apparatus for performing a data migration in a clustered computer system. In one aspect, the availability of the data being migrated is maintained during the migration. In another aspect, a data set is migrated by a transfer utility in one of the hosts in the cluster, and in response to a failure of the host, the migration is resumed without restarting from the beginning point of the data set. In a further embodiment, the hosts in the cluster have agents associated therewith to manage the data migration, and prior to taking at least one action associated with the data migration, the agents coordinate to ensure that the hosts in the cluster are prepared to have the at least one action taken.

Abstract: An apparatus has host ports for coupling hosts to data storage devices. The data storage devices are configured into logical storage units, and the apparatus is programmed with a mapping of the hosts to respective logical storage units. The apparatus decodes a host identifier and a logical storage unit specification from each data access request received at each host port, and determines whether or not the decoded host identifier and logical storage unit specification are in conformance with the mapping in order to permit or deny data access of the logical storage unit through the host port. For example, the apparatus includes a switch for routing the data storage access requests from the host ports to ports that provide access to the data storage, and a set of logical volumes of storage are accessible from each of the ports that provide access to the data storage.

Abstract: A management station includes a management application that controls zoning within devices manufactured or provided from different vendors within a network, such as a data storage network. The management application receives a generic zone control command from a user to control zoning within a device in the network. The management application translates the zone control command to one or more vendor specific device zone control commands in a vendor specific device command set that is specifically designed to control zoning within devices from a specific vendor. To perform the translation, the management application identifies the vendor of one or more devices that are affected by the zone control command. Based on this identification, the management application selects an appropriate vendor specific device command set that contains vendor specific zone control commands.

Abstract: Methods and apparatus for managing access to a plurality of storage resources in a computer system including a host computer and a storage system. The host computer comprises an application layer including at least one application program, and the computer system includes a plurality of storage resources visible to the application layer. The computer system has an access facility that grants access to the plurality of storage resources and requires a privilege level for the at least one application program to be granted access. In one aspect, requests to access one of the plurality of storage resources from the application layer are intercepted, and at least one of the intercepted requests is modified in a manner that will impact the access facility in determining whether the requestor satisfies the privilege level to be granted access to the one of the plurality of storage resources.

Abstract: Method and apparatus for managing access to one of a plurality of raw storage devices in a computer system including a host computer and a storage system. The computer system includes a plurality of logical volumes of data that are visible to the host computer and the storage system and are perceived by the host computer as comprising a plurality of raw storage devices. The host computer includes a file system/LVM mapping layer. In accordance with one aspect of the invention, a request, from a requester having less than system administrator access privileges, to perform an action directly on the one of the plurality of raw storage devices is granted, so that a logical channel is provided to directly access the one of the plurality of raw storage devices without the logical channel being mapped by the file system/LVM mapping layer. Another aspect is directed to a computer system including a host computer comprising an application layer including at least one application program.

Abstract: A storage controller has at least one physical data port for a data network including host processors. The storage controller is programmed to provide a plurality of virtual ports for access to storage, and a virtual switch for routing storage access requests from the physical port to the virtual ports. The virtual ports and the virtual switch are defined by software. The virtual ports appear to the hosts as physical ports in the data network. For example, in a Fiber-Channel network, the virtual ports have World Wide Names (WWNs) and are assigned temporary addresses (S_IDs), and the virtual switch provides a name server identifying the WWNs and S_IDs of the virtual ports. For convenient partitioning of storage among host processors, one or more virtual ports are assigned to each host, and a set of storage volumes are made accessible from each virtual port.