Abstract: A technique is directed to storing data on a plurality of storage devices of a data storage array. The technique involves, on each storage device of the plurality of storage devices, providing large disk extents and small disk extents for allocation to RAID extents. The technique further involves forming, from the large disk extents, a user-data RAID extent to store user data for the data storage array. The technique further involves forming, from the small disk extents, an internal-metadata RAID extent to store internal metadata for the data storage array. In some arrangements, spare space is reserved on one or more storage devices between large and small disk extents.

Abstract: A technique is directed to storing data on a plurality of storage devices of a data storage array. The technique involves, on each storage device of the plurality of storage devices, providing large disk extents and small disk extents for allocation to RAID extents. The technique further involves forming, from the large disk extents, a user-data RAID extent to store user data for the data storage array. The technique further involves forming, from the small disk extents, an internal-metadata RAID extent to store internal metadata for the data storage array. In some arrangements, spare space is reserved on one or more storage devices between large and small disk extents.

Abstract: Techniques for sharing private space among storage system components. The techniques include determining an amount of private space for each of a rebuild component, an FSCK component, and a deduplication component, reserving private space equal to the sum of (i) the amount determined for the rebuild component and (ii) the maximum of the amounts determined for the FSCK and deduplication components, and allocating the remaining amount of storage space as user space. If a storage device fails, then the rebuild component rebuilds the failed drive data on a hot spare drive in the private space reserved for the rebuild component. If data files become corrupted, then the FSCK component performs offline recovery operations using the private space for the hot spare drive. If such private space for the hot spare drive is unavailable, then the FSCK component performs offline recovery operations using the private space reserved for the deduplication component.

Abstract: Techniques for sharing private space among storage system components. The techniques include determining an amount of private space for each of a rebuild component, an FSCK component, and a deduplication component, reserving private space equal to the sum of (i) the amount determined for the rebuild component and (ii) the maximum of the amounts determined for the FSCK and deduplication components, and allocating the remaining amount of storage space as user space. If a storage device fails, then the rebuild component rebuilds the failed drive data on a hot spare drive in the private space reserved for the rebuild component. If data files become corrupted, then the FSCK component performs offline recovery operations using the private space for the hot spare drive. If such private space for the hot spare drive is unavailable, then the FSCK component performs offline recovery operations using the private space reserved for the deduplication component.

Abstract: A technique forms storage containers within a group of storage devices. The technique involves partitioning each storage device of the group of storage devices into slices having a same storage size. The technique further involves creating, from the slices having the same storage size, first extents having a first extent width and second extents having a second extent width. The first extent width is different from the second extent width. The technique further involves provisioning (i) at least one first extent from the first extents having the first extent width to form a first storage container within the group of storage devices and (ii) at least one second extent from the second extents having the second extent width to form a second storage container within the group of storage devices. The first storage container and the second storage container share at least one storage device.

Abstract: A method includes (a) receiving a setup command directing a computing device to create a protocol endpoint to allow a remote host device to access storage volumes of the computing device presented to the remote host through the protocol endpoint as virtual storage volumes, (b) in response to receiving the setup command, creating a logical storage device object representing the protocol endpoint, the logical storage device object having zero underlying storage capacity, (c) subsequent to creating the logical storage device object, receiving a command directed at the protocol endpoint, and (d) in response to receiving the command, processing the command by a driver stack on the computing device containing the logical storage device object representing the protocol endpoint, the driver stack being shorter than another driver stack on the computing device used to process storage commands directed at another logical storage device object having non-zero underlying storage.

Abstract: Embodiments are directed to implementing the protocol endpoint (PE) as a LUN object without significant modification to also support additional features. In particular, since many of the additional features are similar to those already implemented within storage group objects, it would be desirable to implement a PE using both a LUN object and a storage group object linked together. This result may be accomplished by implementing the PE as a LUN object is used when certain features are being accessed and as a storage group object that is used when other features are being accessed. This linkage may be achieved by indexing both the storage group object and the LUN object representing the PE using the same World Wide Name.

Abstract: Determining port failover information is described. First information is determined by a first storage processor executing first code for performing port matching. The first information identifies a first set of port pairs. Each port pair includes a first port of the first or second storage processor and a second port of the first or second storage processor. Each port pair denotes the first port as protecting the second port. Upon failure or unavailability of the second port, the first port virtualizes the second port and requests directed to the second port are redirected to the first port. Similarly, second information is determined by the second storage processor executing second code for performing the port matching. Port failover processing is performed upon failure or unavailability of port(s) of the first storage processor and/or the second storage processor. Port failover processing uses the first information and/or the second information.

Abstract: Described are techniques for coordinating processing to redirect requests. First and second storage processors of a data storage system are provided. Requests are directed to a first set of physical target ports of the first storage processor. The second storage processor is unavailable and has a second set of virtual target ports. Each virtual port of the second set is virtualized by a physical port of the first set. First processing is performed to redirect requests from the second set of virtual ports to a third set of physical ports of the second storage processor. First processing includes booting the second storage processor, directing requests to the third set of physical ports of the second storage processor rather than second set of virtual ports, and queuing requests received at the third set of physical ports until completion of pending requests previously received at the second set of virtual ports.

Abstract: Method and system for managing port failover in storage system comprising first storage processor and first port and second storage processor and second port. Storage system adapted to communicate with FC switch. Storage system providing first and second names characterizing first and second ports to switch for registration such that the first name associated with first port and second name associated with second port. Storage system detects the state of first and second processors. Failure state in first or second processor activates deregistration of port associated therewith. Storage system providing to switch for re-registration one of the names in response to detecting failure in processor associated with one of the ports. The one of the names provided to switch such that the one of the names characterizing the one of the ports is associated with the other of the ports.

Abstract: Described are techniques for processing requests. A request is received at a data storage system. The request is a command to perform first processing and the request is sent from a client over a virtualized path. The virtualized path includes a virtual target port of the data storage system. The virtual target port is a first physical target port that provides a virtualized counterpart port for a second physical target port whereby requests directed to the second physical target port are routed to the first physical target port rather than the second physical target port. First processing is performed and a response to the request is generated. The response includes first information consistent with sending the request over a non-virtualized path to the second physical target port. The response is sent to the client.