Andrew E Dunn

US Patent:

6854035, Feb 8, 2005

Filed:

Oct 5, 2001

Appl. No.:

09/971534

Inventors:

Douglas Paul Dunham - San Jose CA, US
Andrew Dunn - Oceano CA, US
Tina Lynn Dunton - San Jose CA, US
Jason Michael Perkins - Santa Clara CA, US
Ophelia K. Yip - San Francisco CA, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F012/00

US Classification:

711117, 711171

Abstract:

A storage area network (SAN), e. g. , as described above, includes a one or more hosts digital data processors, each having a file system that effects access to one or more storage devices. Each processor is associated with multiple groups from respective levels of a hierarchy, e. g. , a first processor group and a second processor group hierarchically descendant from the first processor group. A process, e. g. , executing on a manager digital data processor, includes a graphical user interface that displays the processor groups as a hierarchical tree. Along, for example, with the identities of the processor groups, nodes of the displayed tree list attributes of the policy defined for each respective group.

US Patent:

8001307, Aug 16, 2011

Filed:

Apr 27, 2007

Appl. No.:

11/796376

Inventors:

Abhijeet P. Gole - San Jose CA, US
Andrew E. Dunn - San Jose CA, US
Prasanna K. Malaiyandi - San Jose CA, US
Shane S. Owara - Sunnyvale CA, US

Assignee:

Network Appliance, Inc. - Sunnyvale CA

International Classification:

G06F 13/00

US Classification:

710240, 711114, 711158, 711162, 707610, 714 411, 709232

Abstract:

An apparatus and a method to eliminate deadlock in a bi-directionally mirrored data storage system are presented. In some embodiments, a first and a second storage servers have established a mirroring relationship. To prevent deadlock between the storage servers and to reduce write latency, the second storage server may hold data received from the first storage server in a replication queue and send an early confirmation to the first storage server before writing the data to a destination volume if the first storage server is held up due to a lack of confirmation. In another embodiment, when the first storage server writes metadata of a persistent point-in-time image (PPI) to the second storage server, the second storage server may send a confirmation to the first storage server after copying the metadata, but before exporting the PPI at the second storage server.

US Patent:

20220350817, Nov 3, 2022

Filed:

Jul 18, 2022

Appl. No.:

17/866594

Inventors:

- San Jose CA, US
Andrew Eric Dunn - Sunnyvale CA, US
Yi Yang - San Jose CA, US

International Classification:

G06F 16/27
G06F 16/21
G06F 3/06
G06F 11/14
H04L 67/1095

Abstract:

One or more techniques and/or computing devices are provided for non-disruptively establishing a synchronous replication relationship between a primary volume and a secondary volume and/or for resynchronizing the primary volume and the secondary volume. For example, a baseline snapshot and one or more incremental snapshots of the primary volume are used to construct and incrementally update the secondary volume with data from the primary volume. A dirty region log is used to track modifications to the primary volume. A splitter object is used to split client write requests to the primary volume and to the secondary volume. A synchronous transfer engine session is initiated to processing incoming client write requests using the dirty region log. A cutover scanner is used to transfer dirty data from the primary volume to the secondary volume. In this way, a synchronous replication relationship is established between the primary volume and the secondary volume.

US Patent:

20200081633, Mar 12, 2020

Filed:

Nov 13, 2019

Appl. No.:

16/682099

Inventors:

- Sunnyvale CA, US
Ripulkumar Hemantbhai Patel - Fremont CA, US
Vrishali Dattatray Hajare - Milpitas CA, US
Andrew Eric Dunn - Sunnyvale CA, US
Rithin Kumar Shetty - Sunnyvale CA, US

International Classification:

G06F 3/06
G06F 11/14
G06F 11/20

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.

US Patent:

20190332609, Oct 31, 2019

Filed:

Jul 8, 2019

Appl. No.:

16/504430

Inventors:

- Sunnyvale CA, US
Andrew Eric Dunn - Sunnyvale CA, US
Yi Yang - San Jose CA, US

International Classification:

G06F 16/27
G06F 16/21
H04L 29/08
G06F 3/06
G06F 11/14

Abstract:

One or more techniques and/or computing devices are provided for non-disruptively establishing a synchronous replication relationship between a primary volume and a secondary volume and/or for resynchronizing the primary volume and the secondary volume. For example, a baseline snapshot and one or more incremental snapshots of the primary volume are used to construct and incrementally update the secondary volume with data from the primary volume. A dirty region log is used to track modifications to the primary volume. A splitter object is used to split client write requests to the primary volume and to the secondary volume. A synchronous transfer engine session is initiated to processing incoming client write requests using the dirty region log. A cutover scanner is used to transfer dirty data from the primary volume to the secondary volume. In this way, a synchronous replication relationship is established between the primary volume and the secondary volume.

US Patent:

20180314748, Nov 1, 2018

Filed:

Jul 9, 2018

Appl. No.:

16/029755

Inventors:

- Sunnyvale CA, US
Andrew Eric Dunn - Sunnyvale CA, US
Yi Yang - San Jose CA, US

International Classification:

G06F 17/30
H04L 29/08
G06F 3/06
G06F 11/14

Abstract:

One or more techniques and/or computing devices are provided for non-disruptively establishing a synchronous replication relationship between a primary volume and a secondary volume and/or for resynchronizing the primary volume and the secondary volume. For example, a baseline snapshot and one or more incremental snapshots of the primary volume are used to construct and incrementally update the secondary volume with data from the primary volume. A dirty region log is used to track modifications to the primary volume. A splitter object is used to split client write requests to the primary volume and to the secondary volume. A synchronous transfer engine session is initiated to processing incoming client write requests using the dirty region log. A cutover scanner is used to transfer dirty data from the primary volume to the secondary volume. In this way, a synchronous replication relationship is established between the primary volume and the secondary volume.

US Patent:

20170336997, Nov 23, 2017

Filed:

Aug 7, 2017

Appl. No.:

15/671037

Inventors:

- Sunnyvale CA, US
Ripulkumar Hemantbhai Patel - Fremont CA, US
Vrishali Dattatray Hajare - Milpitas CA, US
Andrew Eric Dunn - Sunnyvale CA, US
Rithin Kumar Shetty - Sunnyvale CA, US

International Classification:

G06F 3/06
G06F 11/14

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.

US Patent:

20170235805, Aug 17, 2017

Filed:

Feb 17, 2016

Appl. No.:

15/045551

Inventors:

- Sunnyvale CA, US
Andrew Eric Dunn - Sunnyvale CA, US

International Classification:

G06F 17/30

Abstract:

One or more techniques and/or computing devices are provided for utilizing a tracking structure for data replication synchronization. For example, a first storage controller, hosting first storage, may have a replication relationship with a second storage controller hosting second storage (e.g., write requests, modifying the first storage, may be replicated to the second storage). The first storage controller maintains a tracking structure comprising hash buckets, dynamic tree structures, and/or a tracking segment bitmap used to identify portions of the first storage as either comprising dirty data (e.g., data, modified by a write request not yet replicated to the second storage, that may be different than corresponding data within the second storage) or clean data (e.g., the same data as the second storage). The tracking structure may be used to resynchronize the second storage to the first storage, perform a quick resync, facilitate semi-synchronous replication, and/or perform snapshot-less resync.