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.

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.

Synchronizing metadata among storage systems synchronously replicating a dataset, where synchronizing the metadata includes: receiving, at a first storage system of the storage systems, an I/O operation directed to the dataset; determining, in dependence upon the I/O operation, a metadata update describing a mapping of segments of content to a virtual address within a storage object, wherein the storage object includes the dataset; and synchronizing metadata on a second storage system of the storage systems by sending the metadata update to the second storage system to update a metadata representation on the second storage system in accordance with the metadata update.

A host device is configured to read and write information from and into a card and to supply a supply voltage that belongs to a first voltage range or a second voltage range which is lower than the first voltage range, and issues a voltage identification command to the card. The voltage identification command includes a voltage range identification section, an error detection section, and a check pattern section. The voltage range identification section includes information indicating which one of the first voltage range and the second voltage range the supply voltage belongs. The error detection section has a pattern configured to enable the card which has received the voltage identification command to detect errors in the voltage identification command. The check pattern section has a preset pattern.

Methods and systems for managing data and transmission of content are disclosed. A computing device may receive a request for content. The computing device may determine data associated with the requested content.

Using host connectivity states to avoid queuing I/O requests: identifying a fault in data communications between a first storage system and a second storage system among a plurality of storage systems across which a dataset is synchronously replicated; updating, upon identifying the fault, an access state of a data communications path between first storage system and a host from an active state to a transitional state with respect to the dataset; and indicating, to the host, a first access state change.

Prioritizing highly performant storage systems for servicing a synchronously replicated dataset: detecting a communication fault between two or more storage systems that are synchronously replicating a dataset; identifying a preferred storage system for winning mediation, including determining that the preferred storage system winning mediation would result in better performance than other storage systems winning mediation; and requesting, by the preferred storage system, mediation from a mediation target.

Prioritizing highly performant storage systems for servicing a synchronously replicated dataset: detecting a communication fault between two or more storage systems that are synchronously replicating a dataset; identifying a preferred storage system for winning mediation, including determining that the preferred storage system winning mediation would result in better performance than other storage systems winning mediation; and requesting, by the preferred storage system, mediation from a mediation target.

Recovery for storage systems synchronously replicating a dataset, including: receiving, by at least one storage system among the plurality of storage systems synchronously replicating the dataset, a request to modify the dataset; generating recovery information indicating whether the request to modify the dataset has been applied on all storage systems in the plurality of storage systems synchronously replicating the dataset; and responsive to a system fault, applying a recovery action in dependence upon the recovery information indicating whether the request to modify the dataset has been applied on all storage systems in the plurality of storage systems synchronously replicating the dataset.

Determining active membership among storage systems synchronously replicating a dataset, where determining active membership includes: detecting, by a particular storage system of the storage systems, a communication fault with one or more of the storage systems, where the particular storage system is configured to request mediation from a mediation target; determining that at least one of the one or more storage systems is configured to request mediation from the mediation target responsive to the communication fault; and responsive to determining that one or more of the storage systems is configured to request mediation from the mediation target, determining whether to request mediation from the mediation target.