One example method includes intercepting an IO issued by an application, writing the IO and IO metadata to a splitter journal in NVM, forwarding the IO to storage, and asynchronous with operations occurring along an IO path between the application and storage, evacuating the splitter journal by sending the IO and IO metadata from the splitter journal to a replication site. In this example, sending the IO and IO metadata from the journal to the replication site does not increase a latency associated with the operations on the IO path

A method and system for co-locating journaling and data storage based on write requests. A write request that includes metadata and data is received from a client. A logical storage unit for storing the metadata and the data is identified. The logical storage unit is divided into a journal partition and a volume partition. The journal partition includes a first log and a second log. Which of the first log and the second log is an active log and which of the first log and the second log is an inactive log are identified. The metadata is recorded in a first location in the active log and the data is recorded in a second location in the active log during a single I/O operation. A reply is sent to the client after the metadata and the data are recorded in the journal partition.

Systems and methods for performing data protection operations including replication operations. A replication operation may automatically learn and predict when a replication system will need to switch modes, such as to a protective mode or to a fast-forward mode. The replication operation ensures that the data is replicated in a manner that optimizes the ability to retain data needed to perform point in time recovery operations while prioritizing the replication operation of new data.

A computer implemented method is provided for determining a delay between a first database and an associated replicated database by replicating transactions of the first database in the replicated database, determining a delay between the two databases based on a commit timestamp from the first database and a timestamp associated with the commit transaction becoming visible in the replicated database. Then, after a predefined period of time has elapsed since replicating the commit transaction, determining a second delay based on a timestamp associated with a heartbeat log and a replicated database system time. And, selectively determining to execute or deny a statement received by the replicated database based on the second delay. Related apparatus, systems, techniques and articles are also described.

Creating and using a virtual cluster may include: creating a first cluster logical device on a first data storage system including data nodes; creating a second cluster logical device on a second data storage system including data nodes; configuring the first cluster logical device and the second cluster logical device as a same first logical device; establishing bidirectional remote replication between the first and second cluster logical devices; determining pairs of data nodes including a data node from the first data storage system and another data node from the second data storage system; determining a failure of a first data node on the first data storage system, wherein one of the pairs of data nodes includes the first data node and a second data node of the second data storage system; and responsive to determining the failure of the first data node, performing failover processing by the second data node.

A method and system for co-locating journaling and data storage based on write requests. A write request that includes metadata and data is received from a client. A logical storage unit for storing the metadata and the data is identified. The logical storage unit is divided into a journal partition and a volume partition. The journal partition includes a first log and a second log. Which of the first log and the second log is an active log and which of the first log and the second log is an inactive log are identified. The metadata is recorded in a first location in the active log and the data is recorded in a second location in the active log during a single I/O operation. A reply is sent to the client after the metadata and the data are recorded in the journal partition.

A technique replicates an index of an operations log (oplog) from a primary node to a secondary node of a cluster in the event of a failure of the primary node. The oplog functions as a staging area to coalesce random write operations directed to a virtual disk (vdisk) stored on a backend storage tier organized as an extent store. The oplog temporarily caches data associated with the random write operations (i.e., write data) as well as metadata describing the write data. The metadata includes descriptors to the write data corresponding to virtual address regions, i.e., offset ranges, of the vdisk and are used to identify the offset ranges of write data for the vdisk that are cached in the oplog. To facilitate fast lookup operations of the offset ranges when determining whether write data io is cached in the oplog, an oplog index provides a state of the latest data for offset ranges of the vdisk. The technique enables fast failover of metadata used to construct the oplog index in memory of a node, such as the secondary node, without downtime or significant metadata replay.

Replicating multiple storage systems utilizing coordinated snapshots, including identifying a replica dataset stored across two or more target storage systems, wherein the replica dataset is a replication target for a source dataset stored across two or more source storage systems; identifying two or more local replicated checkpoints that are replicated from the two or more source storage systems to the two or more target storage systems, wherein two or more local source checkpoints for the two or more local replicated checkpoints are associated with a coordinated source checkpoint for the source dataset; and determining, based on the two or more local replicated checkpoints, a coordinated target checkpoint for the replica dataset.

Metadata logic switches selection of a metadata track from multiple available metadata tracks in a volatile cache to fill the selected metadata track in a metadata track selection interval with metadata entries as source tracks of a source volume are copied to a backup volume of a copy relationship. Destage logic destages to storage a deselected metadata track containing metadata entries generated in a prior metadata track selection interval, while the metadata logic continues to generate and fill additional metadata entries in the selected metadata track in a concurrent metadata track selection interval. Other features and aspects may be realized, depending upon the particular application.

A method and system for performing incremental backup of a network attached storage (NAS) device are described. A storage capture instance associated with a first time instance is received from a network attached storage device. At least a portion of metadata of tracked network packets associated with the network attached storage device is also received. At least one changed content item of the network attached storage device that has changed since the first time instance is identified by analyzing the at least the portion of the metadata of the tracked network packets received. An incremental backup of the network attached storage device is performed at a second time instance based at least in part on the at least one changed content item identified.