Techniques are provided for neutralizing replication errors. An operation is executed upon a first storage object and is replicated as a replicated operation for execution upon a second storage object. A first error may be received for the replicated operation. Instead of transitioning to an out of sync state and aborting the operation, a wait is performed until a result of the attempted execution of the operation is received. If the first error is the same as a second error returned for the operation, then the operation and replicated operation are considered successful and a synchronous replication relationship is kept in sync. If the first error and the second error are different errors, then an error response is returned for the operation and the synchronous replication relationship is transitioned to out of sync.

Managing connectivity to synchronously replicated storage systems, including: identifying a plurality of storage systems across which a dataset is synchronously replicated; identifying a host that can issue I/O operations directed to the dataset; identifying a plurality of data communications paths between the host and the plurality of storage systems across which a dataset is synchronously replicated; identifying, from amongst the plurality of data communications paths between the host and the plurality of storage systems across which a dataset is synchronously replicated, one or more optimal paths; and issuing, to the host, an identification of the one or more optimal paths.

One or more techniques and/or computing devices are provided for replicating virtual machine disk clones. For example, a first storage controller, hosting first storage, may have a synchronous replication relationship with a second storage controller hosting second storage. A virtual machine, within the first storage, may be specified as having synchronous replication protection. Accordingly, virtual machine disk clones of a virtual machine disk of the virtual machine may be replicated from the first storage to the second storage. For example, virtual machine disk clones may be synchronous replicated, replicated by a resync process invoked by a hypervisor agent, and/or stored and replicated from a clone backup directory.

A method is disclosed for use in a storage system including a source system that is coupled to a target system, the method comprising: detecting a rollback event that is associated with a source volume Vs; and performing a rollback of the source volume Vs in response to the rollback event, wherein performing the rollback of the source volume Vs includes: identifying a target snapset Sr to be rolled back to, the target snapset Sr having a creation time Tr; identifying a snapset recovery pair including a source snapset Sk and a target snapset Sk′, the source snapset having a creation time Ts, and the target snapset having a creation time Tt, such that Tr≤Ts≤Tt; assigning the source volume Vs to the source snapset Sk; and update the source volume Vs based on a difference between the target snapset Sr and the target snapset Sk′.

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.

Embodiments of the present invention relate to synchronously replicating data in a distributed computing environment. To achieve synchronous replication both an eventual consistency approach and a strong consistency approach are contemplated. Received data may be written to a log of a primary data store for eventual committal. The data may then be annotated with a record, such as a unique identifier, which facilitates the replay of the data at a secondary data store. Upon receiving an acknowledgment that the secondary data store has written the data to a log, the primary data store may commit the data and communicate an acknowledgment of success back to the client. In a strong consistency approach, the primary data store may wait to send an acknowledgement of success to the client until it receives an acknowledgment that the secondary has not only written, but also committed, the data.

The present disclosure provides a method, system, and device for security object synchronization at multiple nodes of an active-active environment. To illustrate, a source node may generate a corresponding security object sync request for each of multiple target nodes. The source node may send the security object sync request to the target nodes via a source queue and, for each target node, a corresponding distribution queue. A distribution queue may be closed based on an acknowledgement received from a corresponding target node, after a time period, or after a number of transmission attempts. A synchronization log may be maintained to indicate which security object sync requests have been delivered to which target nodes. In some implementations, the source node and the target nodes are part of an active-active environment that may be synchronized in time so the nodes resolve conflicts between received security object updates initiated from two different nodes.

One or more techniques and/or computing devices are provided for resynchronization. For example, a request may be received to create pseudo snapshots of a first consistency group, hosted by a first storage controller, and a second consistency group, hosted by a second storage controller, having a synchronous replication relationship with the first consistency group. Incoming client write requests are logged within an intercept tracking log at the first storage controller. After a first drain without hold of incoming write requests is performed, a first pseudo common snapshot of the second consistency group is created. After a second drain without hold of incoming write operations is performed, a second pseudo common snapshot of the first consistency group and the intercept tracking log is created. The pseudo snapshots and the intercept tracking log (e.g., indicating a delta between the pseudo snapshots) are used to resynchronize the first and second consistency groups.