公开(公告)号：US20220317896A1

公开(公告)日：2022-10-06

申请号：US17219740

申请日：2021-03-31

Applicant: NetApp, Inc.

Inventor： Arul Valan ,  Anoop Vijayan ,  Akhil Kaushik

IPC: G06F3/06

Abstract: Systems and methods for making a cross-site storage solution resilient towards mediator unavailability are provided. According to one embodiment, a stretched storage system is operable to bring a mediator associated with a primary and secondary distributed storage system back into the role of an arbitrator for peered consistency groups (CGs). A mediator reseed status indicator is maintained for multiple CGs to identify when the mediator's status information for a CG is stale. When the mediator becomes available and a local CG is identified as the subject of a mediator reseed process, the master node of the primary that hosts a master copy of a dataset for the local CG performs the reseed process, including: (i) causing relationship status information for the local CG to be updated on the mediator to the current state maintained by the primary; and (ii) resetting the mediator reseed status indicator.

公开(公告)号：US11360867B1

公开(公告)日：2022-06-14

申请号：US17219746

申请日：2021-03-31

Applicant: NetApp, Inc.

Inventor： Murali Subramanian ,  Sohan Shetty ,  Akhil Kaushik

IPC: G06F11/20 ,  H04L67/1097

Abstract: Systems and methods for re-aligning data replication configuration of a cross-site storage solution after a failover are provided. According to one embodiment, after a failover, the new primary distributed storage system orchestrates flipping of the data replication configuration of a peered consistency group (CG) to reestablish zero RPO and zero RTO protections for the peered CG. The primary causes the secondary distributed storage system to perform an atomic database operation on its remote configuration database to (i) delete an existing source configuration that identifies the secondary as a source of data replication; and (ii) persist a new destination configuration identifying the secondary as a destination of data replication. Then, the primary performs an atomic database operation on its local configuration database to (i) delete an existing destination configuration identifying the primary as the destination; and (ii) persist a new source configuration identifying the distributed storage system as the source.

公开(公告)号：US11262931B2

公开(公告)日：2022-03-01

申请号：US16683427

申请日：2019-11-14

Applicant: NetApp Inc.

Inventor： Michael Robin Eisler ,  Santosh Ananth Rao ,  Akhil Kaushik ,  Yuedong Mu

IPC: G06F3/06 ,  G06F11/20

Abstract: One or more techniques and/or computing devices are provided for synchronous replication. For example, synchronous replication relationships are established between a first storage object (e.g., a file, a logical unit number (LUN), a consistency group, etc.), hosted by a first storage controller, and a plurality of replication storage objects hosted by other storage controllers. In this way, a write operation to the first storage object is implemented in parallel upon the first storage object and the replication storage objects in a synchronous manner, such as using a zero-copy operation to reduce overhead otherwise introduced by performing copy operations. Reconciliation is performed in response to a failure so that the first storage object and the replication storage objects comprise consistent data. Failed write operations and replication write operations are retried, while enforcing a single write semantic. Dependent write order consistency is enforced for dependent write operations, such as overlapping write operations.

公开(公告)号：US20210406280A1

公开(公告)日：2021-12-30

申请号：US17472723

申请日：2021-09-13

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Anoop Chakkalakkal Vijayan ,  Preetham Kudgi Shenoy

IPC: G06F16/27

Abstract: Techniques are provided for transitioning a first storage object and a second storage object from an asynchronous replication state to a synchronous replication state. Metadata operations are logged into a metadata log. Dirty data, modified by data operations executed upon the first storage object, are tracked using a dirty region log. Metadata operations are replicated from the metadata log to the second storage object during a metadata drain phase. During the metadata drain phase, incoming operations are logged into the metadata log when the metadata log has a non-zero size, otherwise, the metadata operations are replicated to the second storage object. After the metadata drain phase, a data drain phase is performed using the dirty region log.

公开(公告)号：US11120048B2

公开(公告)日：2021-09-14

申请号：US16293807

申请日：2019-03-06

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Anoop Chakkalakkal Vijayan ,  Preetham Kudgi Shenoy

IPC: G06F16/27

Abstract: Techniques are provided for transitioning a first storage object and a second storage object from an asynchronous replication state to a synchronous replication state. Metadata operations are logged into a metadata log. Dirty data, modified by data operations executed upon the first storage object, are tracked using a dirty region log. Metadata operations are replicated from the metadata log to the second storage object during a metadata drain phase. During the metadata drain phase, incoming operations are logged into the metadata log when the metadata log has a non-zero size, otherwise, the metadata operations are replicated to the second storage object. After the metadata drain phase, a data drain phase is performed using the dirty region log.

公开(公告)号：US20200218695A1

公开(公告)日：2020-07-09

申请号：US16819246

申请日：2020-03-16

Applicant: NetApp Inc.

Inventor： Vikas Yadav ,  Rajesh Desai ,  Akhil Kaushik

IPC: G06F16/13

Abstract: A system and method for enabling data replication is described. A set of protocol messages can be associated with a set of corresponding set of requests. The associated set of protocol messages can be provided to each of a source storage system and a destination storage system. The source storage system and the destination storage system can be heterogeneous storage systems that implement different types of file systems or file layouts. The source storage system and the destination storage system are enabled to perform a data replication process, in which at least a set of data is to be replicated from the source storage system to the destination storage system, using at least a protocol message from the associated set of protocol messages. The protocol message can correspond to a request for a list of snapshots stored at the source storage system.

公开(公告)号：US20200081633A1

公开(公告)日：2020-03-12

申请号：US16682099

申请日：2019-11-13

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Ripulkumar Hemantbhai Patel ,  Vrishali Dattatray Hajare ,  Andrew Eric Dunn ,  Rithin Kumar Shetty

IPC: G06F3/06 ,  G06F11/14 ,  G06F11/20

Abstract: 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.

公开(公告)号：US20200050587A1

公开(公告)日：2020-02-13

申请号：US16401257

申请日：2019-05-02

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Krishna Murthy Chandraiah setty Narasingarayanapeta

IPC: G06F16/178 ,  G06F16/23 ,  G06F16/27 ,  G06F16/18

Abstract: Techniques are provided for resynchronizing a synchronous replication relationship. Asynchronous incremental transfers are performed to replicate data of a storage object to a replicated storage object. Incoming write requests, targeting the storage object, are logged into a dirty region log during a last asynchronous incremental transfer. Metadata operations, executed on the storage object, are logged into a metadata log during the last asynchronous incremental transfer. Sequence numbers are assigned to the metadata operations based upon an order of execution. The metadata operations are replicated to the replicated storage object for execution according to the sequence numbers, and the dirty regions are replicated to the replicated storage object in response to the metadata operations having been replicated to the replicated storage object. The storage object and replicated storage object are transitioned to a synchronous replication state where incoming operations are synchronously replicated to the replicated storage object.

公开(公告)号：US20200042537A1

公开(公告)日：2020-02-06

申请号：US16401224

申请日：2019-05-02

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Balaji Ramani

IPC: G06F16/27 ,  G06F16/176 ,  G06F11/14 ,  G06F16/11

Abstract: Techniques are provided for synchronous replication based cutover. An asynchronous replication process is executed to perform asynchronous incremental transfers of data of a storage object from a first computing environment to a replicated storage object at a second computing environment until a cutover criteria is met. A synchronous replication process is executed to synchronously replicate operations, targeting the storage object, to the replicated storage object based upon the cutover criteria being met. A cutover is performed to direct operations from targeting the storage object to targeting the replicated storage object based upon the synchronous replication process reaching a steady state of synchronous replication for sub-objects of the storage object, where operations are committed to both the storage object and the replicated storage object.

公开(公告)号：US10423584B2

公开(公告)日：2019-09-24

申请号：US14948653

申请日：2015-11-23

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Yi Yang ,  Yuedong Mu

IPC: G06F16/178 ,  G06F16/16 ,  H04L29/08 ,  G06F3/06 ,  G06F11/20

Abstract: One or more techniques and/or computing devices are provided for implementing synchronous replication. For example, a synchronous replication relationship may be established between a local storage controller hosting local storage and a remote storage controller hosting remote storage (e.g., replication may be specified at a file, logical unit number (LUN), or any other level of granularity). Data file operations may be implemented in parallel upon the local storage and the remote storage. Independent metadata file operations may be independently implemented from data file operations upon the local storage, and upon local completion may be remotely implemented upon the remote storage. In-flight data file operations may be drained before dependent metadata file operations are locally implemented upon the local storage, and upon local completion may be remotely implemented upon the remote storage.