A DBA may pre-generate database recovery jobs on a convenient schedule at a local site, then recover a database at a disaster recovery site. Archive log files for the database that are generated in the interim between recovery job generation and recovery job execution are automatically incorporated into the recovery job when it executes, extending the recovery point closer to the time of the disruption that triggered the need or desire for recovery.

A computing apparatus includes a transaction-record memory and a comparator. The transaction-record memory is to receive and store one or more sequences of transaction records, each transaction record including a unique transaction ID and a transaction payload. The comparator is to compare the payloads of transaction records having the same transaction ID, and to initiate a responsive action in response to a discrepancy between the compared transaction payloads.

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.

The present disclosure relates to a method, a device, and a computer program product for managing a storage system. The storage system includes a first control node, a second control node, and a persistent storage device, the first control node being in an activated state, and the second control node being in a state of transfer from a non-activated state to an activated state. A method includes: loading a first list of page descriptors of the storage system to the second control node to generate a second list of page descriptors at the second control node, the first list including a portion of multiple page descriptors of the storage system that has been modified but has not been flushed to the persistent storage device; receiving a synchronization message from the first control node that indicates that the first list has been modified by the first control node; and updating the second list at the second control node based on the synchronization message. Further, a corresponding device and a corresponding program product are provided. With the example implementations of the present disclosure, the start performance of the control nodes in the storage system can be improved.

A method and a system for reconstructing a slot table for Network File System (NFS) based distributed file systems are provided herein. The method includes: receiving a retried request from a client at a node of the distributed file system; in a case that the retried request is of a re-enter idempotent type, processing the request again; in a case that the retried request is file state related, checking in already opened file handles if they are open with exactly same properties already exist for the particular client, and if found, returning the file handle information to the client as if it was just opened by it; and in a case that the retried request is of a non-idempotent type attempting to perform the operation again, wherein if the source file does not exist, checking the existence of the expected outcome, and replying with a success.

A terminal apparatus includes a memory that has a program area divided in a plurality of blocks, each blocks being set write protection, and a processor coupled to the memory and configured to set a priority level of stored data to each blocks of the memory, respectively, change the priority level to a lower level in accordance with a failure of an internal of the terminal apparatus when the failure is detected, release the write protection in accordance with the changed priority level, and write data that has a possibility of elimination, to the block whose write protection has released, in accordance with the failure.

A computer-implemented method may comprise receiving proposals to mutate a data stored in a distributed and replicated file system coupled to a network, the distributed and replicated data system comprising a plurality of nodes, each comprising a server. A metadata service maintains and updates a replica of a namespace of the distributed and replicated file system and coordinates updates to the data by generating an ordered set of agreements corresponding to the received proposals, the ordered set of agreements specifying an order in which the nodes are to mutate data stored in data nodes and cause corresponding changes to the state of the namespace. For each agreement in the generated ordered set of agreements, a corresponding writers list may be provided that comprises an ordered list of nodes to execute the agreement and make corresponding changes to the namespace. The ordered set of agreements may then be sent to the plurality of nodes along with, for each agreement in the ordered set of agreements, the corresponding writers list or a pre-generated index thereto and each of the plurality of nodes may be configured to only execute agreements for which it is a first-listed node on the received writers list.

Sync-mark (SM) detection recovery techniques for HDDs tend to be slow and cumbersome. Typical approaches often require an entire read command to be aborted and multiple subsequent read commands with significant firmware intervention. Should a data sector be unreadable, an example recovery technique for HDDs is recursive read averaging (RRA). Using RRA, samples for failed sector reads are stored in memory. When a sector is subsequently read, the samples are averaged and replace the prior sample stored in memory. The averaged samples are then used to decode the sector. Should SMs associated with data fragments making up a sector be unreadable, the data fragments are unreadable, rendering the sector unreadable. The systems and methods described herein are used to recover previously unreadable SMs. When updated data fragments are subsequently recombined, the confidence level in the overall sector is improved, which increases the likelihood of a successful decode of the sector.

A computer cluster includes a group of connected computers that work together essentially as a single system. Each computer in the cluster is called a node. Each node has a boot device configured to load an image of an operating system into the node's main memory. Sometimes the boot device of a first node experiences a problem that prevents the operating system from loading. This can affect the entire cluster. Some aspects of the disclosure, however, are directed to operations that determine the problem with the first node's boot device based on a communication sent via a first communications network. Further, the operations can communicate to the first node a copy of boot data from a second node's boot device. The copy of the boot data is sent via a second communications network different from the first communications network. The copy of the boot data can solve the first boot device's problem.

A storage system forms a high availability pair for data duplication using a first volume of a first storage apparatus as a primary volume and a second volume of a second storage apparatus as a secondary volume. The first volume and a third volume of a third storage apparatus are used as a primary volume and a secondary volume, respectively, to form an asynchronous copy pair. The second volume and the third volume are used as a primary volume and a secondary volume, respectively, to form a standby pair. When a command to form the asynchronous copy pair is received, the storage system refuses to form the asynchronous copy pair when the standby pair is not formed yet.