Included within a shared housing are at least one user interface element; a first isolated computational entity; a second isolated computational entity; and a switching arrangement. The switching arrangement is configured to, in a first mode, connect the first isolated computational entity to the at least one user interface element; and, in a second mode, connect the second isolated computational entity to the at least one user interface element.

Technology is disclosed for recovering I/O modules in a storage system using in-band alternate control path (ACP) architecture (“the technology”). The technology enables a storage server to transmit control commands, e.g., for recovering an I/O module, to the I/O module over a data path that is typically used to transmit data commands. The control commands are typically transmitted using ACP that is separate from the data path. By enabling transmission of control commands over the data path, the technology eliminates the need for separate medium for ACP, at least in part, to transmit the control commands. The technology can be implemented in a pure in-band ACP mode, which supports recovering an I/O module of a storage shelf in which at least one I/O module is responsive, and/or in a mixed in-band ACP mode, which supports recovery of I/O modules of a storage shelf in which all I/O modules are non-responsive.

A configuration for a component of a primary node is synchronized with a configuration for a component of a partner node in a different cluster by replicating the primary node configuration with the partner node. A baseline configuration replication comprises a snapshot of a component configuration on the primary. The baseline configuration can be generated by traversing through the configuration objects, capturing their attributes and encapsulating them in a package. The baseline package can then be transferred to the partner node. The configuration objects can be applied on the partner node in the order in which they were captured on the primary node. Attributes of the configuration objects are identified that are to be transformed. Values for the identified attributes are transformed from a name space in the primary node to a name space in the partner node.

The method begins with a processing module determining whether to reconstruct data corresponding to a plurality of data slices when the plurality of data slices is to be transferred from a first type of memory device to a second type of memory device. The method continues with the processing module retrieving the plurality of data slices from a first set of memory devices that are of the first type of memory, reconstructing at least a portion of the data from the plurality of data slice in accordance with a first error coding dispersal function to produce reconstructed data, encoding the reconstructed data in accordance with a second error coding dispersal function to produce a second plurality of data slices, and storing the second plurality of data slices in a second set of memory devices that are of the second type of memory when the data is to be reconstructed.

The present disclosure relates to a method, a device, and a computer program product for managing a storage system. The storage system includes a first control node, a second control node, and a persistent storage device, the first control node being in an activated state, and the second control node being in a state of transfer from a non-activated state to an activated state. A method includes: loading a first list of page descriptors of the storage system to the second control node to generate a second list of page descriptors at the second control node, the first list including a portion of multiple page descriptors of the storage system that has been modified but has not been flushed to the persistent storage device; receiving a synchronization message from the first control node that indicates that the first list has been modified by the first control node; and updating the second list at the second control node based on the synchronization message. Further, a corresponding device and a corresponding program product are provided. With the example implementations of the present disclosure, the start performance of the control nodes in the storage system can be improved.

Techniques for configuring paths for transmitting I/O operations may include: configuring a first path over which logical devices are exposed over a first port of a data storage system to a second port of a host, wherein the logical devices include a first logical device having a first service level objective and a second logical device having a second service level objective denoting a lower service level than the first service level objective; determining whether there is a service level objective violation of the first service level for the first logical device; and responsive to determining there is a service level objective violation for the first logical device, performing first processing that exposes the first logical device and the second logical device over different ports of the data storage system. Masking information may indicate which logical devices are exposed over which data storage system ports to which host ports.

A method includes transmitting a solicitation message to target storage units of a plurality of storage units of a storage network, where the solicitation message solicits the target storage units to store encoded data slices of a first data segment of data, and where the message is not sent to other storage units of the plurality of storage units. The method further includes receiving favorable responses from at least some of target storage units, and determining an error coding function based on an amount of the favorable responses and data storage requirements for the first data segment. The method further includes encoding the first data segment in accordance with the error coding function to produce a plurality of encoded data slices. The method further includes outputting the plurality of encoded data slices to storage units of the at least some of the target storage units for storage therein.

Integrated circuits such as application specific integrated circuits or programmable logic devices may include multiple copies of a same circuit together with a majority vote circuit in a configuration that is sometimes also referred to as multi-mode redundancy. An adder circuit may be coupled to these multiple copies and produce a carry-out signal and a sum signal based on signals received from the multiple copies. The carry-out signal of the adder circuit may provide the result of the majority vote operation. A logic exclusive OR gate may perform a logic exclusive OR operation between the sum signal and the carry-out signal, thereby generating an error signal. The error signal may indicate that one of the multiple copies produces an output that is different than the outputs produced by the other copies.

A data storage network is provided. The network includes a client connected to the data storage network; a plurality nodes on the data storage network, wherein each data node has two or more RAID controllers, wherein a first RAID controller of a first node is configured to receive a data storage request from the client and to generate RAID parity data on a data set received from the client, and to store all of the generated RAID parity data on a single node of the plurality of nodes.

The disclosed embodiments disclose techniques for synchronizing file updates between two cloud controllers of a distributed filesystem. Two or more cloud controllers collectively manage distributed filesystem data that is stored in the cloud storage systems; the cloud controllers ensure data consistency for the stored data, and each cloud controller caches portions of the distributed filesystem. During operation, a cloud controller receives a request from a client to access a file in the distributed filesystem. The cloud controller sends a synchronization update request for the file to a second cloud controller and in response receives a synchronization update for the file from the second cloud controller.