Abstract: In some examples, a distributed computer system includes a plurality of computer nodes, where the plurality of computer nodes include respective programs to cooperate to perform a workload. A first computer node includes a communication proxy between the program of the first computer node and a communication library that supports communications between the program of the first computer node and the programs of other computer nodes of the plurality of computer nodes, and a fault management service to monitor a health of the other computer nodes, and in response to a detection of a fault of a second computer node of the plurality of computer nodes, relaunch the communication proxy. The relaunched communication proxy selects, from a plurality of states, a common state to which the programs are to roll back.

Abstract: A computer-implemented method for testing failover may include: determining one or more cross-regional dependencies and traffic flow of an application in a first region of a cloud environment, wherein the one or more cross-regional dependencies include a dependency of the application in the first region of the cloud environment to one or more applications in at least one other region of the cloud environment; determining a risk score associated with performing failover of the application to a second region of the cloud environment at least based on the determined one or more cross-regional dependencies and traffic flow of the application; comparing the determined risk score with a predetermined risk score; in response to determining that the determined risk score is lower than the predetermined risk score, performing failover of the application to the second region of the cloud environment; isolating the second region of the cloud environment from the first region of the cloud environment for a predetermined

Abstract: A file system in a user space partition of virtual memory may be mounted by a computing device that runs a virtual machine which includes a set of storage disks. The file system in user space may then expose one or more virtual files associated with one or more storage disks that correspond to one or more loop devices configured to map files of the virtual machine to the one or more virtual files. The computing device may then receive a request to read a data block stored at the virtual machine and may identify a file and corresponding virtual file that stores the requested data block based on a set of metadata provided by the loop devices. The computing device may then determine the location of the data block stored at the virtual machine, and may read the data block from the determined location.

Abstract: A technique provides efficient data failover by creation and deployment of a protection policy that ensures maintenance of frequent common snapshots between sites of a multi-site data replication environment. A global constraint optimizer executes on a node of a cluster to create the protection policy for deployment among other nodes of clusters at the sites. Constraints such as protection rules (PRs) specifying, e.g., an amount of tolerable data loss are applied to a category of data designated for failover from a primary site over a network to a plurality of (secondary and tertiary) sites typically located at geographically separated distances. The optimizer processes the PRs to compute parameters such as frequency of snapshot generation and replication among the sites, as well as retention of the latest common snapshot maintained at each site to create a recovery point and configuration of the protection policy that reduces network traffic for efficient use of the network among the sites.

Abstract: A method of remote device diagnosis and mitigation includes receiving a signal indicative of an intermittent technical state of a first device. Immediately responsive thereto, the method includes interrogating the first device for parameters. The method includes interrogating the first device for the parameters at a third time outside receipt of the signal. The parameters include a transient parameter present at a first time of the intermittent technical state and not present a second time following the first time. The method includes recording the parameters from the first time in a first data file and the parameters for the third time in an additional data file. The first data file is compared with the additional data file to identify a difference in a parameter indicative of a cause of the intermittent technical state. The method includes remotely implementing a change on the first device to mitigate the cause.

Abstract: Provided is a system, method, and computer program product for handling fault tolerance in a blockchain enabled network system. The system includes a computing system with at least one of a plurality of processors arranged as an active processor node, at least one data storage device including a first ledger corresponding to a first blockchain and a second ledger corresponding to a second blockchain, at least one standby processor node, and at least one standby data storage device. The at least one active processor node is programmed or configured to analyze and record blocks corresponding to data received through the network system on the first ledger and the second ledger such that the first ledger and the second ledger have matching data, detect at least one failure or anticipated failure, and in response to detecting the at least one failure or anticipated failure, generating a switch-over command.

Abstract: The present disclosure provides a state management method, a method for switching between a master application server and a backup application server, and an electronic device. In present disclosure, the management server updates the recorded backup application server state in time by querying for the connection state of the hot-backup connection between the master application server and the backup application server, and when the master application server is in failure, instead of immediately controlling the master application server and the backup application server to perform switching between the master and backup application servers, the management server controls the master application server and the backup application server to perform master-backup switching between the application servers according to the recorded backup application server state.

Abstract: Embodiments described herein are generally directed to intelligent management of microservices failover. In an example, responsive to an uncorrectable hardware error associated with a processing resource of a platform on which a task of a service is being performed by a primary microservice, a failover trigger is received by a failover service. A secondary microservice is identified by the failover service that is operating in lockstep mode with the primary microservice. The secondary microservice is caused by the failover service to takeover performance of the task in non-lockstep mode based on failover metadata persisted by the primary microservice. The primary microservice is caused by the failover service to be taken offline.

Abstract: Provided is a device for providing error information using a graphical user interface (GUI) includes: a communication circuit configured to communicate with a server that provides a web application; a display; a memory; and a processor. The processor is configured to: receive user information, request information, and response information of each user; to display user objects, respectively on the display so that a user related to an error of the web application is distinguished based on the user information and the response information; to display action objects on the display so that an action related to the error is distinguished based on the request information and the response information, if one of the user objects is selected; and to output error information related to the selected action object to the display based on the request information and the response information if one of the action objects is selected.

Abstract: A semiconductor device includes a data bus, a data memory, a selector, a processor, and a debug controller. The selector is configured to be controlled by the debug controller to be in either a first selecting state in which the processor transmits a first signal to the data bus and a second selecting state in which the debug controller transmits a second signal to the data bus. The debug controller is configured to control the state of the selector based on the reception state of a predetermined command from an external device as well as the states of a read enable signal and a write enable signal from the processor such that, when the selector is in the second selecting state, the debug controller accesses the data bus via the selector.

Abstract: In the disaster recovery system exemplified by the information processing system, the cloud management node manages the importance information indicating the importance placed on the performance of each application to be executed by the primary site in correspondence with the virtual computer for executing the application, determines the DR method applied to the virtual computer and the application by selection from multiple types of DR methods based on the importance information of the corresponding application for each of the virtual computers, and determines a content of a predetermined set item applied to transfer of data to be used by the virtual computer.

Abstract: A method for active failure recovery of a single node improved based on PBFT algorithm is disclosed. The abnormal node first initiates a view change request, if (2f+1) view change requests containing the same view value cannot be received within a specified period of time, the abnormal node enters a state to be recovered, and the node to be recovered initiates a recovery request to all nodes of the whole network, waits for replies from normal nodes and counts the number of replies, calculates a height of stable checkpoint of the whole network after receiving replies contain the same view value from (2f+1) nodes, and update the state thereof to finally complete the recovery. This method solves an inherent problem in the PBFT algorithm that a failure in a single node cannot be recovered autonomously, so that a practicability of the PBFT algorithm is greatly improved.

Abstract: Automated disaster recovery site failover of a messaging platform is disclosed. A processor establishes a communication link between a first data center site and a second data center site via a communication network. The first data center site includes a first database in an active state and the second data center site includes a second database in a passive state during which data replication flows from the first database to the second database. The processor monitors states of the first database and the second database; detects, in response to monitoring, that the first database has changed its state from the active state to the passive state and that the second database has changed its state from the passive state to the active state; and automatically switches, in response to detecting, the data replication flows during which the data replication flows from the second database to the first database.

Abstract: A computing device for configuring a redundant system includes: a detection unit configured to detect another computing device newly added to the redundant system during operation of the computing device; and a construction processing unit configured to execute construction processing for constructing a redundant configuration with the other computing device.

Abstract: Techniques are provided for on-demand serverless disaster recovery. A primary node may host a primary volume. Snapshots of the primary volume may be backed up to an object store. In response to failure, a secondary node and/or an on-demand volume may be created on-demand. The secondary node may provide clients with failover access to the on-demand volume while a restore process restores a snapshot of the primary volume to the on-demand volume. In some embodiments, there was no secondary node and/or on-demand volume while the primary node was operational. This conserves computing resources that would be wasted by otherwise hosting the secondary node and/or on-demand volume while clients were able to access the primary volume through the primary node. Modifications directed to the on-demand volume are incrementally backed up to the object store for subsequently restoring the primary volume after recovery.

Abstract: Techniques for peer node recovery can include: receiving a notification regarding an occurrence of a trigger condition which indicates to perform recovery processing for a first storage device of a first node, wherein the first storage device is used as a boot device for the first node; and responsive to receiving the notification of the trigger condition, performing recovery processing for the first storage device of the first node comprising: performing a network boot of the first node over an internal network connection using a preboot execution (PXE) server of the second node; reimaging the first storage device of the first node using content from a second storage device of the second node, wherein the content includes a bootable partition comprising an operating system; and using the bootable partition of the first storage device of the first node, booting the first node to load and run the operating system.

Abstract: A plug-in based framework provides high availability (HA), including fault tolerance, in a distributed system, such as provided by a virtualized computing environment. The framework uses blueprints that define entities to be monitored, failure conditions, failover actions, restoration actions, and other aspects associated with HA. Microservices execute the blueprints, and a load balancer may balance the execution of the blueprints amongst microservices.

Abstract: A method and a computer system for core recovery management are provided. A first operation signal is generated via a first hardware agent. The first operation signal indicates that the first hardware agent is processing an operation requested by a first processor core. The first processor core receives a first extend fence signal based on the generated first operation signal. As long as the first extend fence signal is received via the first processor core, the first processor core is kept in a fenced state for core recovery.

Abstract: Methods and systems implement a data recovery bypassing protocol, by which a storage node of a cloud network may return a replica of lost data being recovered to timely service a read operation call from a computing node of the cloud network, without waiting for completion of a first, a second, and a third recovery function. Storage devices implement asynchronous event reporting (“AER”) protocol between a storage engine and storage devices of the storage node. Within a storage device, an AER generation protocol enables a storage controller and a flash memory cell array of the storage device to intercommunicate, and enables the storage controller to generate AER messages. By bypassing secondary recovery, the computing node may successfully read lost data from many or all storage nodes of the cloud network, thus completing read operation calls without suffering milliseconds in performance loss and blocking, averting observable degradation of QoS of the overall computing system.

Abstract: Data server and client device logs may be transmitted over a network for analysis to identify potential issues such as errors. Because the logs may include significant amounts of data, the logs may be transmitted through a quantum smart grid network that leverages Li-Fi technology for increased bandwidth and improved latency. Analysis and resolution identification may be performed by an analysis server that is supported by multiple cloud systems. Each cloud system may be independent operated from other cloud systems, and may include one or more cloud servers configured to analyze log feeds and/or identify resolutions for detected issues. The analysis server may be configured to distribute tasks to the cloud systems based on a variety of factors, and further provide switchover and failover functionality between different cloud systems depending on communication or processing conditions.