Abstract: An apparatus comprises at least one processing device that includes a processor coupled to a memory. The processing device is configured to control delivery of input-output (IO) operations from a host device to at least one storage system over selected ones of a plurality of paths through a network, wherein the paths are associated with respective initiator-target pairs, the initiators being implemented on the host device and the targets being implemented on the storage system. The processing device is further configured to identify one or more of the plurality of paths that each exhibits at least a threshold amount of mismatch between a negotiated rate of its initiator and a negotiated rate of its target, and to modify path selection in the host device to at least temporarily avoid selecting the one or more identified paths. The processing device illustratively comprises at least a portion of the host device.

Abstract: An apparatus comprises a first host device that is configured to communicate over a network with a storage system. The first host device is configured to obtain information on a bandwidth usage by a second host device of one or more ports of the storage system and to determine a bandwidth limit of the one or more ports of the storage system. The first host device is further configured to submit data to the one or more ports at a given bandwidth that is determined based at least in part on the obtained information and the determined bandwidth limit of the one or more ports of the storage system.

Abstract: An apparatus in one embodiment comprises a host device configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device comprises an MPIO driver that is configured to deliver input-output operations from the host device to the storage system over the network. The MPIO driver is configured to obtain a command generated by the host device under a first protocol for communicating with one or more of the storage devices. The command is directed to a target storage device of the plurality of storage devices. The target storage device is configured to communicate using a second protocol that is different than the first protocol. The MPIO driver is further configured to convert the command for communication under the second protocol and to provide the converted command to the target storage device.

Abstract: An apparatus comprises at least one processing device comprising a processor coupled to a memory. The processing device is configured to control performance of a migration process in which a source logical storage device of a first storage system is migrated to a target logical storage device of a second storage system. In conjunction with the migration process, the processing device is further configured to update a management header of the target logical storage device to include an identifier of the target logical storage device, to store an identifier of the source logical storage device, and responsive to a read of the management header of the target logical storage device, to return the identifier of the source logical storage device in place of the identifier of the target logical storage device. Other illustrative embodiments include methods and computer program products.

Abstract: An apparatus comprises at least one processing device that is configured to control delivery of input-output operations from a host device to a storage system over selected ones of a plurality of paths through a network, wherein the paths are associated with respective initiator-target pairs, the initiators being implemented on the host device and the targets being implemented on the storage system. The at least one processing device is further configured to identify a particular one of the initiators that comprises multiple virtual initiators having respective virtual identifiers, to determine a negotiated rate of the particular initiator, to determine a negotiated rate of a corresponding one of the targets, and to limit amounts of bandwidth utilized by the multiple virtual initiators in communicating with the corresponding target based at least in part on the negotiated rate of the particular initiator and the negotiated rate of the corresponding target.

Abstract: An apparatus comprises a host device configured to communicate over a network with first and second storage systems. The host device detects an association in at least one of the first and second storage systems between a source logical storage device of the first storage system and a target logical storage device of the second storage system, and responsive to the detected association, establishes a migration session in the host device for migration of the source logical storage device to the target logical storage device. The host device also obtains an indication from at least one of the first and second storage systems that a corresponding migration session has been activated in the first and second storage systems, and activates the previously-established migration session in the host device based at least in part on the obtained indication for migration of the source logical storage device to the target logical storage device.

Abstract: Techniques for processing I/O operations may include: issuing, by a process of an application on a host, an I/O operation; determining, by a driver on the host, that the I/O operation is a read operation directed to a logical device used as a log to log writes performed by the application, wherein the read operation reads first data stored at one or more logical addresses of the logical device; storing, by the driver, an I/O flag in the I/O operation, wherein the I/O flag has a first flag value denoting an expected read frequency associated with the read operation; sending the I/O operation from the host to the data storage system; and performing first processing of the I/O operation on the data storage system, wherein said first processing includes using the first flag value in connection with caching the first data in a cache of the data storage system.

Abstract: An apparatus comprises a host device configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device is further configured to execute multiple processes that generate input-output (IO) operations for delivery to the storage system. The host device comprises a multi-path input-output (MPIO) driver configured to store for each of one or more of the storage devices information specifying one or more of the processes executing on the host device that are permitted to access that storage device, and for each of at least a subset of the IO operations, to determine the particular storage device to which the IO operation is directed, to identify the process that generated the IO operation, and to control delivery of the IO operation based at least in part on whether or not the stored information indicates that the identified process is permitted to access the particular storage device.

Abstract: A host device is configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device comprises a multi-path input-output (MPIO) driver configured to control delivery of input-output (IO) operations from the host device to the storage system over selected ones of a plurality of paths through the network, where the paths are associated with respective initiator-target pairs, and each of a plurality of targets of the initiator-target pairs comprises a corresponding port of the storage system. The MPIO driver is further configured to obtain from the storage system information characterizing failure status of at least a subset of the targets, and to update availability status of the paths based at least in part on the obtained information.

Abstract: A host device comprises a processor coupled to a memory. The host device is configured, for each of a plurality of initiators of the host device from which write operations are sent to a storage system for processing, to repeatedly send to the storage system a command to obtain from the storage system write pressure information maintained by the storage system for that initiator, and responsive to the write pressure information obtained from the storage system for a corresponding one of the initiators indicating that the corresponding initiator is associated with a write pressure condition, to at least temporarily reduce a rate at which the write operations are sent from the corresponding initiator to the storage system. The operations of repeatedly sending the command, and at least temporarily reducing the rate, are illustratively performed by at least one multi-path input-output driver of a multi-path layer of the host device.

Abstract: A host device is configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device comprises a multi-path input-output (MPIO) driver configured to control delivery of input-output (IO) operations from the host device to the storage system over selected ones of a plurality of paths through the network. The MPIO driver is further configured to determine IO processing performance for each of at least a subset of the paths, and to dynamically adjust a path selection algorithm utilized in selecting particular ones of the paths for delivery of the IO operations from the host device to the storage system based at least in part on the determined performance. For example, dynamically adjusting a path selection algorithm illustratively comprises activating a particular one of a plurality of distinct path selection algorithms available to the MPIO driver and/or adjusting one or more parameters of a given path selection algorithm.

Abstract: A host device is configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device comprises a multi-path input-output (MPIO) driver configured to control delivery of input-output (IO) operations from the host device to the storage system over selected ones of a plurality of paths through the network, where the paths are associated with respective initiator-target pairs, and each of a plurality of targets of the initiator-target pairs comprises a corresponding port of the storage system. The MPIO driver is further configured to obtain from the storage system information characterizing failure status of at least a subset of the targets, and to update availability status of the paths based at least in part on the obtained information.

Abstract: Service level objectives (SLOs) defined for a storage system are associated with VMs running on hosts. For an I/O operation for a virtual machine (VM) running on a host system, storage processing is performed on the I/O operation in accordance with the SLO defined for the VM. The same storage system-defined SLOs may be applied to VMs running on multiple host systems. SLOs may be maintained by the storage array and shared with one or more host systems in I/O communication with the storage system. SLOs may be defined using a user interface of a storage system, host system, virtualizer control station or other component of a storage network, and communicated to the storage system, which may maintain the SLOs, and may disseminate them to one or more hosts. The SLOs then may be associated with VMs running on the hosts and tagged to I/O communications corresponding to the VMs.

Abstract: Service level objectives (SLOs) defined for a storage system are associated with virtual machines running on hosts. For an I/O operation for a virtual machine (VM) running on a host system, storage processing is performed on the I/O operation in accordance with the SLO defined for the VM. The same storage system-defined SLOs may be applied to VMs running on multiple host systems. SLOs may be maintained by the storage array and shared with one or more host systems in I/O communication with the storage system. SLOs may be defined using a user interface of a storage system, host system, virtualizer control station or other component of a storage network, and communicated to the storage system, which may maintain the SLOs, and may disseminate them to one or more hosts. The SLOs then may be associated with VMs running on the hosts and tagged to I/O communications corresponding to the VMs.

Abstract: An apparatus in one embodiment comprises a host device that includes a set of input-output (IO) queues and a current multi-path input-output (MPIO) driver configured to select IO operations from the set of IO queues for delivery to the storage system. The current MPIO driver groups a plurality of paths from the host device to a logical volume of the storage system into a current multi-path logical device. The host device installs a target MPIO driver and migrates control of the multi-path logical device to the target MPIO driver from the current MPIO driver where the migration comprises generating a duplicate multi-path logical device for the target multi-path input-output driver, adding a new path to the current multi-path logical device that routes input-output operations to the duplicate multi-path logical device, and removing one or more paths of the current multi-path logical device other than the added new path.

Abstract: An apparatus comprises a host device configured to communicate over a network with a storage system. The host device comprises a plurality of nodes each comprising a plurality of processing devices and at least one communication adapter. The host device comprises a multi-path input-output (MPIO) driver that is configured to obtain an input-output (IO) operation that targets a given logical volume. The MPIO driver identifies a source node and a plurality of paths between the source node and the given logical volume. The MPIO driver determines a load factor and a distance for each identified path. The MPIO driver determines a weight associated with each identified path based at least in part on the determined load factor and distance and selects a target path based at least in part on the determined weight. The MPIO driver delivers the obtained IO operation to the given logical volume via the selected target path.

Abstract: An apparatus comprises a host device configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device is configured to implement a multi-path input-output driver for delivery of input-output operations from the host device to the storage system over the network. The multi-path input-output driver is configured to perform, in user space of the host device, discovery of paths to logical storage volumes of the storage system, to identify two or more of the paths providing connection to a given one of the logical storage volumes, to generate, in the user space of the host device, a given multi-path logical device grouping the identified two or more paths providing connection to the given logical storage volume, and to submit input-output operations directed to the given logical storage volume via the given multi-path logical device in the user space of the host device.

Abstract: An apparatus comprises a host device configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device is further configured to execute multiple processes that generate input-output (IO) operations for delivery to the storage system. The host device comprises a multi-path input-output (MPIO) driver configured to store for each of one or more of the storage devices information specifying one or more of the processes executing on the host device that are permitted to access that storage device, and for each of at least a subset of the IO operations, to determine the particular storage device to which the IO operation is directed, to identify the process that generated the IO operation, and to control delivery of the IO operation based at least in part on whether or not the stored information indicates that the identified process is permitted to access the particular storage device.

Abstract: An apparatus comprises a host device configured to communicate over a network with a storage system comprising a plurality of storage devices. The host device comprises a set of input-output queues and a multi-path input-output driver configured to select input-output operations from the set of input-output queues for delivery to the storage system over the network. The multi-path input-output driver is further configured to maintain payload size counters to track outstanding command payload for respective ones of a plurality of paths from the host device to the storage system, to detect an oversubscription condition relating to at least one of the paths based at least in part on values of one or more of the payload size counters, and to initiate one or more automated actions responsive to the detected oversubscription condition.

Abstract: An apparatus comprises a host device configured to communicate over a network with a storage system. The host device comprises a multi-path input-output driver configured to control delivery of input-output operations from the host device to the storage system over selected ones of a plurality of paths through the network. The multi-path input-output driver is further configured to collect information characterizing input-output patterns for each of a plurality of different applications executing on the host device, and to provide the collected information to a machine learning system. The machine learning system utilizes the collected information to generate one or more application predictions based at least in part on analysis of observed input-output patterns. The collected information in some embodiments comprises statistical distributions of numbers of input-output operations having payload sizes falling into specified ranges over a given time period.