公开(公告)号：US20230325361A1

公开(公告)日：2023-10-12

申请号：US18335710

申请日：2023-06-15

Applicant: NetApp Inc.

Inventor： Rithin Kumar Shetty ,  Akhil Kaushik ,  Nagender Somavarapu ,  Yuedong Mu ,  Pranab Patnaik

IPC: G06F16/178 ,  G06F16/188 ,  G06F11/14 ,  G06F11/20 ,  G06F9/455 ,  H04L67/1095

CPC classification number: G06F16/178 ,  G06F16/188 ,  G06F11/1484 ,  G06F11/2076 ,  G06F11/2082 ,  G06F9/45558 ,  G06F11/1464 ,  H04L67/1095 ,  G06F2009/45562 ,  G06F2009/45583 ,  G06F2201/84

Abstract: 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.

公开(公告)号：US11762814B2

公开(公告)日：2023-09-19

申请号：US17486027

申请日：2021-09-27

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Gaurav Verma

IPC: G06F7/00 ,  G06F16/178 ,  G06F9/54

CPC classification number: G06F16/178 ,  G06F9/54

Abstract: Techniques are provided for synchronous replication for synchronous mirror copy guarantee. A file system dependent technique for synchronous mirror copy guarantee is provided by overriding default behavior of a persistent fence so that the persistent fence is activated to block operations targeting a storage object having a synchronous replication relationship based upon the synchronous replication relationship being out of sync. The default behavior of the persistent fence is overridden to allow operations to be executed upon the storage object based upon the synchronous replication relationship being in sync. A file system independent technique for synchronous mirror copy guarantee is provided by intercepting operations before the operations are received by a file system. The operations are selectively forwarded to the file system or not based upon a state of a synchronous replication relationship.

公开(公告)号：US20230289076A1

公开(公告)日：2023-09-14

申请号：US18320788

申请日：2023-05-19

Applicant: NetApp, Inc.

Inventor： Murali Subramanian ,  Akhil Kaushik ,  Anoop Vijayan ,  Omprakash Khandelwal ,  Arun Kumar Selvam

IPC: G06F3/06

CPC classification number: G06F3/0631 ,  G06F3/0604 ,  G06F3/067

Abstract: Systems and methods are described for efficiently performing various operations at the granularity of a consistency group (CG) within a cross-site storage solution. An example of one of the various operations includes an independent and parallel resynchronization approach that independently brings individual volumes of a CG to a steady state of in-synchronization (InSync), thereby contributing to scalability of CGs by supporting CGs having a large number of member volumes without requiring a change to the resynchronization process. Another example includes preserving dependent write-order consistency when a remote mirror copy goes out-of-synchronization (OOS) for any reason by driving all member volumes OOS responsive to any member volume becoming OOS. Yet another example includes independent creation of snapshots by member volumes to support efficient and on-demand creation by an application of a common snapshots of all or a subset of peered member volumes of a CG with which the application is associated.

公开(公告)号：US11709743B2

公开(公告)日：2023-07-25

申请号：US17219815

申请日：2021-03-31

Applicant: NetApp, Inc.

Inventor： Rakesh Bhargava ,  Akhil Kaushik ,  Divya Kathiresan ,  Mukul Verma

IPC: G06F11/00 ,  G06F11/20 ,  G06F11/14 ,  G06F11/30 ,  G06F11/07

CPC classification number: G06F11/2069 ,  G06F11/0772 ,  G06F11/1453 ,  G06F11/2023 ,  G06F11/3034

Abstract: Multi-site distributed storage systems and computer-implemented methods are described for providing an automatic unplanned failover (AUFO) feature to guarantee non-disruptive operations (e.g., operations of business enterprise applications, operations of software application) even in the presence of failures including, but not limited to, network disconnection between multiple data centers and failures of a data center or cluster.

公开(公告)号：US20230119175A1

公开(公告)日：2023-04-20

申请号：US18066775

申请日：2022-12-15

Applicant: NetApp, Inc.

Inventor： Akhil Kaushik ,  Anoop Vijayan ,  Omprakash Khandelwal

IPC: G06F11/20 ,  G06F3/06

Abstract: Systems and methods are described for a non-disruptive planned failover from a primary copy of data at a primary storage system to a mirror copy of the data at a cross-site secondary storage system. According to an example, a planned failover feature of a multi-site distributed storage system provides an order of operations such that a primary copy of a first data center continues to serve I/O operations until a mirror copy of a second data center is ready. This planned failover feature improves functionality and efficiency of the distributed storage system by providing non-disruptiveness during planned failover - even if various failures occur. The planned failover feature also includes a persistent fence to avoid serving I/O operations during a timing window when both primary data storage and secondary data storage are attempting to have a master role to serve I/O operations and this avoids a split-brain situation.

公开(公告)号：US20230110776A1

公开(公告)日：2023-04-13

申请号：US18053561

申请日：2022-11-08

Applicant: NetApp, Inc.

Inventor： Murali Subramanian ,  Akhil Kaushik ,  Anoop Vijayan ,  Arun Kumar Selvam

IPC: G06F3/06

Abstract: Systems and methods are provided for bringing a volume of a consistency group (CG) into an in-synchronization (InSync) state while other volumes of the CG remain in the InSync state. According to an example, in order to support recovery from disruptive events in a manner that ensures a zero recovery point objective (RPO) guarantee and insulates an application making use of the CG from adverse impacts, responsive to a triggering event, a Fast Resync process may first be attempted to promptly bring an affected volume back into an in-synchronization (InSync) state from an out of synchronization (OOS) state while allowing other members of the CG to remain in the InSync state. Should the Fast resync process be unsuccessful in bringing the volume back into the InSync state within a predetermined or configurable time threshold, then a second type of resynchronization process may be employed at the CG level.

公开(公告)号：US20220357854A1

公开(公告)日：2022-11-10

申请号：US17510788

申请日：2021-10-26

Applicant: NetApp, Inc.

Inventor： Krishna Murthy Chandraiah Setty Narasingarayanapeta ,  Akhil Kaushik ,  Nagaraj Lalsangi

IPC: G06F3/06

Abstract: In one embodiment, a method comprises maintaining state information regarding a data synchronous replication status for a storage object of a primary storage cluster and a replicated storage object of a secondary storage cluster. The method includes temporarily disallowing input/output (I/O) operations for the storage object when the storage object of the primary storage cluster has a failure, which causes an internal state as out of sync for the storage object while maintaining an external state as in sync for external entities. The method performs persistent inflight tracking and reconciliation of I/O operations with a first Op log of the primary storage cluster and a second Op log of the secondary storage cluster and performs a resynchronization between the storage object and the replicated storage object based on the persistent inflight tracking and reconciliation of I/O operations.

公开(公告)号：US11461280B2

公开(公告)日：2022-10-04

申请号：US16401257

申请日：2019-05-02

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Krishna Murthy Chandraiah setty Narasingarayanapeta

IPC: G06F16/178 ,  G06F16/27 ,  G06F16/23 ,  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：US20220124149A1

公开(公告)日：2022-04-21

申请号：US17567182

申请日：2022-01-03

Applicant: NetApp Inc.

Inventor： Paul Anthony Powell ,  Akhil Kaushik ,  Srikumar Natarajan ,  Ching-Yuk Paul Ngan

IPC: H04L67/1095 ,  G06F16/178 ,  G06F16/182 ,  G06F3/06 ,  G06F11/20 ,  H04L67/1097

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 first storage controller hosting local storage and a second 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 operations and offloaded operations may be implemented in parallel upon the local storage and the remote storage. Error handling operations may be implemented upon the local storage and implement in parallel as a best effort on the remote storage, and a reconciliation may be performed to identify any data divergence from the best effort parallel implementation. Storage area network (SAN) operations may be implemented upon the local storage, and upon local completion may be remotely implemented upon the remote storage.

公开(公告)号：US20220091749A1

公开(公告)日：2022-03-24

申请号：US17543351

申请日：2021-12-06

Applicant: NetApp Inc.

Inventor： Akhil Kaushik ,  Anil Kumar Ponnapur ,  Aravind Srinivasa Raghavan ,  Manoj Kumar V. Sundararajan

IPC: G06F3/06

Abstract: One or more techniques and/or computing devices are provided for resilient replication of storage operations. For example, a first storage controller may host first storage having a replication relationship with second storage hosted by a second storage controller. To improve resiliency against transient network issues of a network between the storage controllers, the first storage controller may implement a queue and retry mechanism to retry replication operations not acknowledge back by the second storage controller within a threshold time. The second storage controller may maintain a cumulative sequence number of a latest replication operation performed in order, an operation response map of replication operations performed out of order, and an operation finder map identifying currently implemented replication operations, which may be used to process incoming replication operations. Single write semantics, write order consistency, and reduction of write amplification may be provided.