Abstract: Methods, apparatus and systems receive an IO reroute request for a first system to reroute an IO request with a target storage device that is disconnected from the first system and provides proxy communication of the IO request with the target storage device on behalf of the first system based on the received IO reroute request, using at least a second system that is connected to the same target storage device.

Abstract: Swapping from an active address space to a shadow address space may include: initializing, for an active address space, a shadow address space; receiving a request to swap from the active address space to the shadow address space; in response to the request, copying state information from the active address space to the shadow address space; and swap usage of the active address space to the shadow address space.

Abstract: Storage device swap in a multiple computing cluster environment using cross system communication includes sending, by a first host device of a first computing cluster of a plurality of computing clusters, a swap trigger command to one or more storage devices shared across the plurality of computing clusters indicating that a swap event is to be triggered. The swap trigger command identifies the one or more storage devices to participate in the swap event. The first host device receives a signal to trigger the swap event from a storage controller associated with the one or more storage devices, a signal to trigger the swap event.

Abstract: Designation of a swap control system in a group of peers within a computing cluster includes determining a processing unit resource capacity for each of a plurality of computing systems in a peer group within a computing cluster, and determining a swap capability for each of the plurality of computing systems. Designation of a swap control system in a group of peers within a computing cluster further includes designating one of the plurality of computing systems as a control system for a swap operation within the peer group based on the processing unit resource capacity and the swap capability of the designated one of the plurality of computing systems relative to the processing unit resource capacity and the swap capability of each of the other computing systems of the plurality of computing systems.

Abstract: Storage device swap in a multiple computing cluster environment based on peer-to-peer remote copy state change includes detecting that a peer-to-peer remote copy (PPRC) state change event has occurred on a first storage device shared across a plurality of computing clusters. A first computing cluster of the plurality of the plurality of computing clusters determines that the PPRC state change event was not caused by the first computing cluster. A swap event to swap from usage of the first storage device to usage of a second storage device shared across the plurality of computing clusters is initiated responsive to the determining that the PPRC state change event was not caused by the first computing cluster.

Abstract: Coordinating an unplanned swap event across multiple computing clusters includes receiving a notification from each of a plurality of computing clusters through a shared storage device of a set of storage devices. The notification identifies which of a first set of target storage devices and a second set of target storage devices that a particular computing cluster of the plurality of computing clusters is capable of swapping to from a set of source storage devices. Based on the notification from each of the plurality of computing clusters, it is determined whether the plurality of computing clusters will swap from usage of the set of source storage devices to the first set of target storage devices or to the second set of target storage devices during a swap event.

Abstract: Triggering a storage system swap event based on device error impact includes monitoring for input/output (I/O) errors on each of a plurality of storage devices of a first storage system. A criticality attribute of each of the plurality of storage devices is determined. A device score is calculated for each of the plurality of storage devices based on a number of I/O errors detected for the storage device. A swap score value for the first storage system is calculated based on the criticality attribute of each of the plurality of storage devices and the device score for each of the plurality of storage devices. Whether to either perform or bypass a storage swap event is determined based on the swap score value, wherein the storage swap event includes swapping between usage of the first storage system and a second storage system by a computing system.

Abstract: Determining an unplanned swap event risk level for a storage system includes monitoring for input/output (I/O) errors on each of a plurality of storage devices of a first storage system within a predetermined time interval. A criticality level of the first storage system is determined. A risk level for an unplanned swap event is calculated based on detected I/O errors for each of the plurality of storage devices and the criticality level of the first storage system. The unplanned swap event includes swapping between usage of the first storage system and a second storage system by a computing system. The risk level for the unplanned swap event is provided.

Abstract: Provided is a method for correcting untrusted data and avoiding logical device swapping for at least one logical subsystem of at least one computer system. A processor may monitor a primary storage for one or more errors that indicate untrusted data on the primary storage. An error indicating that a data set on the primary storage is an untrusted data set may be identified. In response to the error being identified, a corresponding uncompromised version of the data set may be read from a secondary storage. The corresponding uncompromised version of the data set may be written over the untrusted data set on the primary storage.

Abstract: Provided is a method for correcting pinned data in a primary storage. A primary storage controller may detect a pinned data set on a primary storage. In response to detecting the pinned data set, the primary storage controller may instruct a secondary storage controller to transmit a copy of the pinned data set to the primary storage controller. The copy of the pinned data set may be stored in a secondary storage that is communicatively coupled to the secondary storage controller. The secondary storage may include a synchronous copy of the primary storage. The primary storage controller may receive the copy of the pinned data set from the secondary storage controller. The primary storage controller may also write the copy of the pinned data set over the pinned data set on the primary storage.

Abstract: A method for limiting I/O access in shared storage systems is disclosed. In one embodiment, such a method includes establishing, for a volume, a list of address spaces that are authorized to access the volume. The method further receives an I/O request to access the volume and determines whether the I/O request originates from one of the address spaces identified in the list. If the I/O request originates from one of the address spaces in the list, the method passes the I/O request to the volume. If, on the other hand, the I/O request does not originate from one of the address spaces in the list, the method blocks the I/O request. A corresponding system and computer program product are also disclosed.

Abstract: Provided are a computer program product, system, and method for after swapping from a first storage to a second storage, mirroring data from the second storage to the first storage for data in the first storage that experienced data errors. A swap operation redirects host Input/Output (I/O) requests to data from the first server to the second server in response to a health condition at the first server. A determination is made of data errors with respect to data in the first storage that experienced data errors. The second server is instructed to mirror data in the second storage to the first server including data for the data in the first storage that experienced the data errors to store in the first storage in response to determining that the first server is available for the data mirroring operations.

Abstract: Provided are a computer program product, system, and method for managing health conditions to determine when to restart replication after a swap triggered by a storage health event. A determination is made of a health condition with respect to access to a first storage that triggers a swap operation. The swap operation redirects host Input/Output (I/O) requests to data from a first server to a second server in response to determining the health condition. After the swap operation the I/O requests are directed to the second server and a second storage. The second server is instructed to mirror data in the second storage to the first server to store in the first storage in response to determining that the health condition is resolved.

Abstract: Provided is a method for correcting untrusted data and avoiding logical device swapping for at least one logical subsystem of at least one computer system. A processor may monitor a primary storage for one or more errors that indicate untrusted data on the primary storage. An error indicating that a data set on the primary storage is an untrusted data set may be identified. In response to the error being identified, a corresponding uncompromised version of the data set may be read from a secondary storage. The corresponding uncompromised version of the data set may be written over the untrusted data set on the primary storage.

Abstract: Provided is a method for correcting pinned data in a primary storage. A primary storage controller may detect a pinned data set on a primary storage. In response to detecting the pinned data set, the primary storage controller may instruct a secondary storage controller to transmit a copy of the pinned data set to the primary storage controller. The copy of the pinned data set may be stored in a secondary storage that is communicatively coupled to the secondary storage controller. The secondary storage may include a synchronous copy of the primary storage. The primary storage controller may receive the copy of the pinned data set from the secondary storage controller. The primary storage controller may also write the copy of the pinned data set over the pinned data set on the primary storage.

Abstract: A method for collecting diagnostic information associated with an I/O error is disclosed. In one embodiment, such a method includes detecting an error associated with an input/output (I/O) operation. The method determines whether the error can be re-driven and, if so, enables various diagnostic functions to improve collection of diagnostic information. The method then immediately re-drives the I/O operation associated with the error in order to recreate the error. Using the diagnostic functions that have been enabled, the method captures diagnostic information associated with the recreated error. A corresponding system and computer program product are also disclosed.

Abstract: Provided is a method for correcting pinned data in a primary storage. A primary storage controller may detect a pinned data set on a primary storage. In response to detecting the pinned data set, the primary storage controller may instruct a secondary storage controller to transmit a copy of the pinned data set to the primary storage controller. The copy of the pinned data set may be stored in a secondary storage that is communicatively coupled to the secondary storage controller. The secondary storage may include a synchronous copy of the primary storage. The primary storage controller may receive the copy of the pinned data set from the secondary storage controller. The primary storage controller may also write the copy of the pinned data set over the pinned data set on the primary storage.

Abstract: Provided is a method for correcting untrusted data and avoiding logical device swapping for at least one logical subsystem of at least one computer system. A processor may monitor a primary storage for one or more errors that indicate untrusted data on the primary storage. An error indicating that a data set on the primary storage is an untrusted data set may be identified. In response to the error being identified, a corresponding uncompromised version of the data set may be read from a secondary storage. The corresponding uncompromised version of the data set may be written over the untrusted data set on the primary storage.

Abstract: A method for monitoring I/O is disclosed. In one embodiment, such a method includes identifying various stages of an I/O process. The method further monitors progress of an I/O operation as it advances through the stages of the I/O process. The method records, in a data structure associated with the I/O operation, timing information indicating time spent in each of the stages. This timing information may include, for example, entry and exit times of the I/O operation relative to each of the stages. In the event the I/O operation exceeds a maximum allowable time spent in one or more of the stages, the method generates an error. Various recovery actions may be taken in response to the error. A corresponding system and computer program product are also disclosed.

Abstract: A method for dynamically tuning I/O performance is disclosed. In one embodiment, such a method includes identifying various stages of an I/O process. The method further monitors progress of an I/O operation as it advances through the stages of the I/O process. The method records, in a data structure associated with the I/O operation, timing information indicating time spent in each of the stages. This timing information may include, for example, entry and exit times of the I/O operation relative to each of the stages. In the event the I/O operation exceeds a maximum allowable time spent in one or more of the stages, the method automatically adjusts an allocation of computing resources to one or more stages of the I/O process. A corresponding system and computer program product are also disclosed.