Emc IP Holding Company LLC

Alcatel Lucent

Tianfang Xiong

Hongru Xu

Yuanyang Wu

Yifeng Lu

Qiu Shang

Fei Long

Minghui Zhang

Wai Chuen Yim

Qi Qu

Yue Qian

Lei Gao

Chen Gong

He Wang

Yue Yang

Vasu Subramanian

Weibing Zhang

Zhipeng Zhang

Binbin Deng

Shaocong Liang

Xiaohua Ma

Ruisong Wang

Joseph Yuan Gu

Mancheng Xiong

A method of performing synchronous replication from a primary storage system apparatus (PSSA) to a secondary storage system apparatus (SSSA) is provided. The method includes (a) in response to write requests received by the PSSA, (i) calculating metadata changes by the PSSA for accommodating the write requests, (ii) generating, by the PSSA, metadata journal log entries that describe the metadata changes, and (iii) mirroring the metadata journal log entries from the PSSA to the SSSA; (b) regenerating the metadata changes by the SSSA based on the metadata journal log entries mirrored from the PSSA to the SSSA; and (c) writing the regenerated metadata changes to persistent storage of the SSSA. A method performed by the SSSA is also provided. An apparatus, system, and computer program product for performing similar methods are also provided.

Reducing redundancy in synchronous replication of metadata with a journal log

Techniques manage application systems in an application environment. The application environment includes a first application system, a second application system and a third application system. First snapshot information of a first group of snapshots of the first application system is obtained, the first application system being in active state. Second snapshot information of a second group of snapshots of the second application system is obtained, the second application system being in standby state. It is determined whether the second application system and the third application system have a common snapshot based on the first snapshot information and the second snapshot information. Data is synchronized to the third application system depending on whether the second application system and the third application system have a common snapshot. Overheads required during data synchronization may be reduced as far as possible, and the efficiency of data synchronization may be improved.

Method, device, and computer program product for managing application system

A method is used for bitmap-based synchronous replication in a data protection system. The method includes, upon re-establishing communication with a first storage node, requesting, by a second storage node, a first bitmap from the first storage node. The method includes determining, by the second storage node, a set of data blocks to change on the first storage node based on the first bitmap and a second bitmap on the second storage node. The method also includes sending, by the second storage node to the first storage node, the set of data blocks.

Method and system for bitmap-based synchronous replication

Techniques perform data backup. Such techniques involve: in response to a first storage node to be switched to a second storage node, determining whether there is an ongoing data backup operation between the first storage node and a third storage node; and in response to the ongoing data backup operation between the first and third storage nodes, ceasing the data backup operation. The second storage node is used for backing up data of the first storage node in real time and the third storage node is used for backing up the data of the first storage node periodically. Accordingly, colliding operations can be prevented, system resource can be saved and processing efficiency can be improved.

Method, apparatus and computer program product for data replication

Task management techniques, in a storage system, involve: dividing a task to be processed into a plurality of child tasks, so that a processing time required by each of the plurality of child tasks is same, the number of the plurality of child tasks being a first number; dividing a progress to be reported and being associated with the processing of the task into a plurality of child progresses, the number of the plurality of the child progresses being a second number, the second number being less than the first number, and each of the plurality of child progresses having a same value; and associating, based on the first and the second number, and according to a predetermined mapping between the plurality of child progresses and the plurality of child tasks, each of the plurality of child progresses with a respective child task of the plurality of child tasks.

Method, device and computer program product for task management

Techniques perform data synchronization. The techniques involve: in response to writing of data to a source storage array, determining whether a transmission link between the source storage array and a destination storage array is disconnected, the data being to be synchronized to the destination storage array; in response to determining that the transmission link is disconnected, accumulating in the source storage array the data written to the source storage array; in response to detecting that the transmission link is recovered, creating a snapshot for a storage unit associated with the data in the destination storage array; and in response to crashing of the source storage array during resynchronization of the data accumulated in the source storage array to the storage unit, restoring the storage unit in the destination storage array using the snapshot. Therefore, the storage space for the snapshot is greatly saved while disaster recovery is ensured.

Method, device and computer readable medium for data synchronization

A technique preserves replication to a storage node. The technique involves, from a first storage node, sending a replication query to a second storage node. The technique further involves, in response to the replication query sent to the second storage node, receiving replication session data from the second storage node. The replication session data describes replication which has terminated from a third storage node to the second storage node for a particular storage object. The technique further involves, based on the replication session data, establishing replication from the first storage node to the second storage node for the particular storage object to preserve use of the particular storage object.

Preserving replication to a storage object on a storage node

Embodiments are directed to techniques for enforcing prerequisite conditions on a data object for an operational feature both upon initiation of that operational feature and while that operational feature is maintained. Accordingly, improved techniques enforce conditions by setting a flag associated with a data object upon confirming that the conditions have been met and checking the flag anytime a configuration change to the data object is requested that would cause the conditions to be violated. If the flag is set, any configuration change that would cause the conditions to be violated is rejected.

Using a flag to selectively permit configuration changes to a data storage object having an activated feature

Replication techniques may include creating a first file pool on a first site where storage for the first pool is provisioned from a first storage device group configured as a first consistency group; creating a second file pool on a second site where storage for the second file pool is provisioned from a second storage device group configured as a second consistency group; creating a first file system and its first snapshot in the first file pool of the first site, where creating the first file system and its first snapshot include performing first modifications to the first file pool; applying the first modifications to the first consistency group; and replicating the first modifications on the second file pool. Replicating may include applying the first modifications to the second consistency group to replicate the first file system and its first snapshot on the second site.

File system snapshot replication techniques

Replication techniques for file-based replication. A first file pool and a second pool may be created, respectively, on a first site and a second site. Storage for the first file pool may be provisioned from a first storage device group configured as a first consistency group. Storage for the second file pool may be provisioned from a second storage device group configured as a second consistency group. Modification operations, such as writes, may be applied to the first file pool. The modifications performed on the first file pool result in corresponding modifications to the first consistency group. The modifications may be replicated on the second file pool by applying the modifications to the second consistency group. File systems created in the first and second file pools may be self-contained and modifications applied to the first and second consistency groups may be applied in a specified order to ensure write consistency.

File-based replication techniques

A technique handles a VDM failover situation. The technique involves adjusting a configuration file on a first platform to indicate whether data managed by an initial VDM on that platform is being replicated to a second platform. The technique further involves, following a VDM failover event, creating a replacement VDM on the first platform to replace the initial VDM. The technique further involves, after the replacement VDM is created, performing an operation that controls interfaces provided by the replacement VDM. The operation enables the interfaces when the operation determines that the data managed by the initial VDM on the first platform was not being replicated to the second platform at the time of the event, and disables the interfaces when the operation determines that the data managed by the initial VDM on the first platform was being replicated to the second platform at that time of the event.

Handling a virtual data mover (VDM) failover situation by performing a network interface control operation that controls availability of network interfaces provided by a VDM

The present invention relates to state transition, especially relates to method and means for state transition of Ethernet linear protection switching. It is provided a method of state transition for a local end of a protection group of Ethernet linear protection switching in a local network element, and the method comprises receiving a first message configured to change the state of the local end with a first state, the first message being overridden by the first state; receiving a second message configured to change the state of the local end; determining a second state of the local end on the basis of the first message and the second message; and changing the state of the local end into the second state. In this way, there will be no unnecessary state transition and then no traffic loss caused by the unnecessary state transition.

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Shanghai, China

Tianfang Xiong