Abstract: Servicing I/O operations in a cloud-based storage system, including: receiving, by the cloud-based storage system, a request to write data to the cloud-based storage system; storing, in solid-state storage of the cloud-based storage system, the data; storing, in object storage of the cloud-based storage system, the data; detecting that at least some portion of the solid-state storage of the cloud-based storage system has become unavailable; identifying data that was stored in the portion of the solid-state storage of the cloud-based storage system that has become unavailable; retrieving, from object storage of the cloud-based storage system, the data that was stored in the portion of the solid-state storage of the cloud-based storage system that has become unavailable; and storing, in solid-state storage of the cloud-based storage system, the retrieved data.

Abstract: A method of operating a storage system, and related storage system, are provided. The storage system establishes resiliency groups, each having a defined level of redundancy of resources of the storage system. The resiliency groups include at least one compute resources resiliency group and at least one storage resources resiliency group. The storage system supports capability of configurations that have multiples of each of the resiliency groups. Blades of the storage system perform distributed data and metadata storage across modular storage devices, in accordance with the resiliency groups.

Abstract: Utilizing multiple redundancy schemes within a unified storage element, including: receiving, in a storage system at a unified storage element that integrates both fast durable storage and bulk durable storage, a data storage operation from a host computer; storing, in accordance with a first data resiliency technique that corresponds to a RAID N+R format, data corresponding to the data storage operation within the fast durable storage of the unified storage element; and responsive to determining that the complete RAID stripe has been written to the fast durable storage, moving a portion of the stored data from the fast durable storage to the bulk durable storage of the unified storage element, the bulk durable storage storing the data in accordance with a second data resiliency technique that corresponds to a RAID M+R format, wherein M is different from N.

Abstract: In a particular embodiment, a dataset that is synchronously replicated across a plurality of storage systems is stored on a particular storage system. The storage system identifies input/output (I/O) requests directed to the dataset. The one or more I/O requests are initiated by an application hosted on a platform of the first storage system. The storage system services the one or more I/O requests directed to the dataset.

Abstract: Creating a modifiable cloned image of a dataset, including: generating, based on a dataset stored within a source data repository, a tracking copy of replica data on a target data repository; generating, after receiving an indication to begin accepting modifications to the tracking copy of the replica data, a cloned image of the dataset that is modifiable without modifying the tracking copy of the replica data; and responsive to a storage operation directed to the target data repository, modifying the cloned image of the dataset without modifying the tracking copy of the replica data.

Abstract: Continuing to service a dataset after prevailing in mediation, including: requesting, by a first storage system, mediation from a mediation service that is configured to resolve which storage system continues to service a dataset after the triggering event, wherein the dataset is synchronously replicated by a plurality of storage systems that includes the first storage system and a second storage system; and detaching the second storage system from a plurality of storage systems synchronously replicating the dataset.

Abstract: Managing storage systems that are synchronously replicating a dataset, including: detecting a change in membership to the set of storage systems synchronously replicating the dataset; and applying one or more membership protocols to determine a new set of storage systems to synchronously replicate the dataset, wherein the one or more membership protocols include a quorum protocol, an external management protocol, or a racing protocol, and wherein one or more I/O operations directed to the dataset are applied to a new set of storage systems.

Abstract: A storage system switching mediators within a storage system synchronously replicating data, where the switching between mediators includes: determining, among one or more of the plurality of storage systems, a change in availability of a first mediator service, wherein one or more of the plurality of storage systems are configured to request mediation from the first mediator service; communicating, among the plurality of storage systems and responsive to determining the change in availability of the first mediator service, a second mediator service to use in response to a fault; and switching, in dependence upon the change in availability of the first mediator service, from the first mediator service to the second mediator service.

Abstract: An illustrative method includes a data protection system determining that data stored by a storage system is under a possible attack, detecting a modify request with respect to the storage system while the data stored by the storage system is under the possible attack, determining that the modify request may be related to the possible attack, and performing, in response to determining that the modify request may be related to the possible attack, a remedial action with respect to the modify request.

Abstract: Establishing a guarantee for maintaining a replication relationship between object stores during a communications outage, an embodiment including identifying, by a first storage system, respective local clock values of one or more second storage systems, wherein the first storage system and the one or more second storage systems are among a plurality of storage systems replicating an object store, wherein the plurality of storage systems are configured to receive requests directed to the replicated object store; determining, by the first storage system in dependence upon the respective local clock values, respective clock differences of the one or more second storage systems relative to the first storage system; and ordering, by the first storage system, one or more updates to the replicated object store in dependence upon the respective clock differences.

Abstract: A uniform model for distinct types of data replication, including receiving, at a source data repository, an update to a dataset; generating, based on the update to the dataset, both metadata describing the update to the dataset and also a metadata representation of the dataset; and initiating, based on the same metadata describing the update to the dataset and also based on the same metadata representation of the dataset, either a first type of data replication or a second type of data replication from among a plurality of types of data replication.

Abstract: Determining storage consumption in group of storage resources, including for the group of data units within a group of storage resources: for each data unit in the group of data units, determining whether the data unit is associated with one or more client entities; and for each data unit associated with one or more client entities, determining a category for the data unit; calculating storage consumption for a client based on the category of each data unit; and reporting the calculated storage consumption.

Abstract: An illustrative method includes maintaining, by a data protection system, a metric associated with a similar block detection process performed by a storage system with respect to data processed by the storage system, the metric representative of a measure of similar blocks in the data as detected by the similar block detection process; determining, by the data protection system, that the metric changes by more than a threshold amount; and determining, by the data protection system based on the determining that the metric changes by more than the threshold amount, that the data processed by the storage system is possibly being targeted by a security threat.

Abstract: A method of distributed file deletion, performed by a storage system, is provided. The method includes receiving, at the storage system, a request to delete a directory and contents of the directory and adding the directory to a first set, listed in a memory in the storage system. The method includes operating on the first set, by examining each directory in the first set to identify subdirectories, adding each identified subdirectory to the first set as a directory, and adding each examined directory to a second set listed in the memory. The method includes deleting in a distributed manner across the storage system without concern for order, contents of directories, and the directories listed in the second set.

Abstract: An illustrative method includes a data protection system identifying one or more input operations and one or more output operations performed between a source and a storage system, identifying an anomaly in a relationship between the one or more input operations and the one or more output operations, and determining, based on the identifying of the anomaly, that the storage system is possibly being targeted by a security threat.

Abstract: An illustrative method includes determining an encryption indicator for a first recovery dataset by determining a difference in an amount or percentage of incompressible data associated with the first recovery dataset compared to an amount or percentage of incompressible data associated with a second recovery dataset that temporally precedes the first recovery dataset, the encryption indicator representative of data within or represented by the first recovery dataset that cannot be compressed more than a threshold amount; and performing, based on the encryption indicator for the first recovery dataset, an action with respect to the second recovery dataset, wherein the second recovery dataset is usable to restore data maintained by a storage system to a second state corresponding to a second point in time that temporally precedes a first point in time corresponding to the first recovery dataset.

Abstract: An illustrative method includes a data protection system detecting a request to perform a restricted operation with respect to a recovery dataset configured to be used by a storage system to recover from a data corruption event within the storage system, monitoring, in response to the request, for an occurrence of a predetermined set of one or more authorization events performed with one or more hardware tokens, and preventing the restricted operation from being executed until the each of the one or more authorization events included in the predetermined set occurs.

Abstract: Synchronously replicating a dataset across cloud-based storage systems, including adding a cloud-based storage system to a set of storage systems that the dataset is synchronously replicated across, where access operations are applied to the dataset equivalently through all storage systems in the set, all storage systems in the set store a separate copy of the dataset, and operations to modify the dataset performed and completed through any of the storage systems in the set are reflected in access operations to read the dataset, the cloud-based storage system including one or more cloud computing instances executing a storage controller application, a virtual drive layer that includes one or more cloud computing instances with local storage for storing at least a portion of the dataset as block data, and an object storage layer for storing at least a portion of the dataset as object data.

Abstract: In one implementation, storage system includes embedded storage devices, where each embedded storage device includes a direct-mapped solid state drive (SSD) storage portion and storage system controllers. The storage system controllers may be operatively coupled to the embedded storage devices via a bus. The storage system controllers may receive data to be written to the plurality embedded storage devices, select a plurality of available allocation units from the direct-mapped SSD storage portions of the plurality of embedded storage devices, respectively, and calculate a verification signature corresponding to the data. The storage system controllers may also write the data and the verification signature to a first subset of the plurality of available allocation units, calculate an erasure code corresponding to the data and the verification signature, and write the erasure code to a second subset of allocation units.

Abstract: A redundant array of independent drives (RAID) stripe is formed across a set of storage controllers of a plurality of storage controllers, wherein the RAID stripe comprises two or more of a plurality of modular storage devices of at least one of the set of storage controllers. The RAID stripe is written across the set of storage controllers.