Abstract: In one aspect, a method includes determining that a first quorum of servers is available at a production site and a target site and generating a group-set bookmark if the first quorum of servers is available. In another aspect, an article includes a non-transitory machine-readable medium that stores executable instructions. The instructions cause a machine to determine that a first quorum of servers is available at a production site and a target site and generate a group-set bookmark if the first quorum of servers is available. In a further aspect, an apparatus includes circuitry configured to determine that a first quorum of servers is available at a production site and a target site; and generate a group -set bookmark if the first quorum of servers available.

Abstract: In one aspect, a method to upgrade software on nodes in a clustered environment, includes terminating processes on a first node before upgrading the software on the first node, upgrading the software to a first version from a second version on the first node, running the processes on the first node after upgrading the software on the first node to the first version, determining whether a second node is about to upgrade to the first version of software, allowing transfer of site control from the second node to the first node, if the second node is about to upgrade to the first version of software and upgrading the software on the second node to the first version of software after the transferring of site control from the second node to the first node.

Abstract: In one aspect, a method includes replicating a first volume of a first storage array to a second volume of a second storage array and notifying a first splitter of a start of migration. The first splitter is configured to send I/Os sent from an application to the first volume to a first data replication appliance (DPA) to be replicated at the second volume and configured to send the I/Os to the first volume. The method also includes configuring a second splitter of a third storage array to: ignore data migrating from the first volume to the third volume and send the I/Os sent from the application to the third volume to the first DPA to be replicated at the second volume and to send the I/Os to the third volume; and migrating data from the first volume to the third volume.

Abstract: In one aspect, a method to provide asymmetric active-active access to a first storage volume using a global cache coupled to a first and second virtual storage volumes includes replicating asynchronously the first storage volume at a first site to a second storage volume at a second site, virtualizing the first storage volume with the first virtual storage volume; and virtualizing the second storage volume with the second virtual storage volume. The first storage volume has primary storage functionality.

Abstract: In a first embodiment, a method and computer program product for use in a storage system comprising quiescing IO commands the sites of an ACTIVE/ACTIVE storage system, the active/active storage system having at least two storage sites communicatively coupled via a virtualization layer, creating a change set, unquiescing IO commands by the virtualization layers, transferring data of a change set to the other sites of the active/active storage system by the virtualization layer, and flushing the data by the virtualization layer. In a second embodiment, a method and computer program product for use in a storage system comprising fracturing a cluster of an active/active storage system; wherein the cluster includes at least two sites, stopping IO on a first site of the cluster; and rolling to a point in time on the first site.

Abstract: In one aspect, a method includes receiving a request to access a virtual volume snapshot, preparing to bind the virtual volume snapshot, intercepting a command to prepare bind of the virtual volume snapshot, rolling back to a point in time corresponding to the requested virtual volume snapshot and generating a virtual volume snapshot in a storage array.

Abstract: In one aspect, a method includes intercepting an I/O sent by a virtual machine at a first site, sending the I/O to a first data protection appliance (DPA) at the first site, sending I/O metadata to a first service layer at the first site, sending I/O data down the I/O stack after receiving acknowledgement that the I/O metadata arrived at the first service layer, intercepting the I/O at the first service layer, sending the I/O metadata from the first service layer to a second service layer at a second site and sending I/O data to the second service layer at the second site by ensuring that I/O metadata mirroring between the first site and the second site is completed before I/O data mirroring occurs between the first site and the second site.

Abstract: Conventional methods of multi-site replication require a data protection appliance (DPA) to split IOs arriving at a volume from a host to a plurality of replica volumes. However, in example embodiments of the present invention, a splitter in the data path may split the IOs to a plurality of replica volumes. In order to create multiple, independent copies of a volume, the splitter will expose the volume to the production site DPA as a plurality of volume instances. Each volume instance may be part of a separate consistency group to be replicated to separate replication sites. Thus, the DPA may attach the splitter to several consistency groups and thus create multiple replicas at one or more replication sites of the same volume.

Abstract: In one aspect, a method includes synchronizing a second storage volume to a first storage volume by synchronizing extents according to priority based on extent activity. In another aspect, an apparatus includes electronic hardware circuitry configured to synchronize a second storage volume to a first storage volume by synchronizing extents according to priority based on extent activity. In a further aspect, an article includes a non-transitory computer-readable medium that stores computer-executable instructions. The instructions cause a machine to synchronize a second storage volume to a first storage volume by synchronizing extents according to priority based on extent activity.

Abstract: In one aspect, a method includes receiving write I/Os for storage in a primary storage array, splitting the write I/Os to a replica site, storing the write I/Os for storage in the storage array in a cache, periodically de-staging the write I/Os in the cache to a volume and after a cache data loss, restoring lost write I/Os from the cache by using the write I/Os split to the replica site.

Abstract: A method, system, and computer program product for data replication, comprising dynamically changing between snapshot hot push and continuous replication; wherein snapshot hot push denotes a replication mode where a snapshot is pushed from the production site to the replication site while IO occurs to the production site.

Abstract: In one aspect, a method includes performing replication of a first volume using a snapshot shipping mode, performing replication of a second volume using a continuous replication mode and generating a consistent point in time for the first and second volumes to enable retrieval of replicated data from the first and second volumes at the consistent point in time.

Abstract: In one aspect, a method to provide synchronous and asymmetric active-active-active access to a first storage volume using a global cache coupled to a first, second and third virtual storage volumes includes replicating asynchronously the first storage volume at a first site to a second storage volume at a second site and mirroring the first storage volume with a third storage volume at a third site. Either one of the first storage volume or the third storage volume has primary storage functionality. The method also includes virtualizing the first storage volume with the first virtual storage volume, virtualizing the second storage volume with the second virtual storage volume and virtualizing the third storage volume with the third virtual storage volume.

Abstract: Conventional method of replication do not allow cascaded replication with journaling. However, in example embodiments of the present invention, a splitter in storage or in the data path may split a single volume to multiple DPA targets. The splitter will intercept data arriving to the volume and split the data to another DPA, thereby allowing cascaded replication. In certain embodiments, the DPA may notify the splitter about a point of consistency because the DPA does not distribute IOs with write order fidelity at all times and only some points are write order fidelity consistent. Thus, the DPA may notify the splitter about a consistent point and the splitter will send notifications about the consistent points to the second DPA, allowing the volumes to have consistent points.

Abstract: A system, method, and computer product for enabling a virtual service layer to consume a first storage medium and a second storage medium and map the storage mediums as one or more virtual storage volumes; wherein the one or more virtual volumes are mirrored at a first site and a second site, mirroring of the virtual storage volumes on a distributed mirror, and enabling a distributed replication service to create a continuous data protection image of the data written to one or more virtual storage volumes.

Abstract: A method, system, and computer program product for replication comprising allowing a subset of sites, wherein the sites comprise a first site, a second site and a third site and further wherein each site has a volume, to have active/active VSL replication, which presents two volumes at two different sites as a single volume, and another set of the sites to have a volume which is a replications of the volume presented by the VSL, and enabling the system to transparently shift which subset of the sites are replicated by the VSL and which sites are replications of the volume presented by the VSL; where the replication of the VSL is performed by a second replication technique.

Abstract: In a first embodiment, a method and computer program product for use in a storage system comprising quiescing IO commands the sites of an ACTIVE/ACTIVE storage system, the active/active storage system having at least two storage sites communicatively coupled via a virtualization layer, creating a change set, unquiescing IO commands by the virtualization layers, transferring data of a change set to the other sites of the active/active storage system by the virtualization layer, and flushing the data by the virtualization layer. In a second embodiment, a method and computer program product for use in a storage system comprising fracturing a cluster of an active/active storage system; wherein the cluster includes at least two sites, stopping IO on a first site of the cluster; and rolling to a point in time on the first site.

Abstract: The punch command may be replicated in a replication environment including a production site and a replication site. The solution includes implementing a punch command to free storage received at a replication site in a replication environment by applying the punch command to storage at the replication site and writing data being freed from the storage at the replication site to an undo stream of a journal at the replication site. If the punch command is not supported, a command to write zeros may be used. Further, an unpunch command is provided for properly undoing a punch command and storing data written to the volume before the punch command freed the storage. Additionally, large punch commands may be split into a plurality to smaller punch commands for efficient journal management. Additionally, volume space may be reclaimed by writing a punch command to the journal instead of zeros.

Abstract: In one aspect, a method includes recovering at least one logical unit of a consistency group in a journal-based replication system without interruption of replication of other logical units in the consistency group, the at least one logical unit being one of a physical logical unit or a virtual logical unit.

Abstract: In one aspect, a method to replicate a key-value pair includes intercepting a command to update a key-value pair in a key-value pair database, the key-value database comprising metadata of a virtual volume, sending an updated key-value pair to a data protection appliance, receiving an acknowledgement that the data protection appliance received the updated key-value pair and updating the key-value pair in the key-value database after the acknowledgement is received.