46 results about "Split-brain" patented technology

Systems, methods, apparatus and software can make use of coordinator resources and SCSI-3 persistent reservation commands to determine which nodes of a cluster should be ejected from the cluster, thereby preventing them from corrupting data on a shared data resource. Fencing software operating on the cluster nodes monitors the cluster for a cluster partition (split-brain) event. When such an event occurs, software on at least two of the nodes attempts to unregister other nodes from a majority of coordinator resources. The node that succeeds in gaining control of the majority of coordinator resources survives. Nodes failing to gain control of a majority of coordinator resources remove themselves from the cluster. The winning node can also proceed to unregister ejected nodes from shared data resources. These operations can be performed in parallel to decrease failover time. The software can continue to execute on all nodes to prevent additional problems should a node erroneously attempt to reenter the cluster.

A system and to prevent data corruption due to split brain in shared data clusters includes two or more nodes of a cluster, a shared storage device, and an update manager. The update manager may be configured to maintain a local persistent store corresponding to each node of the cluster. On receiving an update request directed to the shared storage device from a first node, the update manager may be configured to redirect the update to the local persistent store corresponding to the first node. The update manager may be further configured to verify a cluster membership status of the first node, and to transfer the contents of the update from the local persistent store to the shared storage device if the cluster membership verification succeeds.

Some embodiments provide a method for employing the management and control system of a network to dynamically recover from a split-brain condition in the edge nodes of the network. The method of some embodiments takes a corrective action to automatically recover from a split-brain failure occurred at a pair of high availability (HA) edge nodes of the network. The HA edge nodes include an active machine and a standby machine. The active edge node actively passes through the network traffic (e.g., north-south traffic for a logical network), while the standby edge node is synchronized and ready to transition to the active state, should a failure occur. Both HA nodes share the same configuration settings and only one is active until a path, link, or system failure occurs. The active edge node also provides stateful services (e.g., stateful firewall, load balancing, etc.) to the data compute nodes of the network.

A method, data processing system, and computer program product autonomously migrate clients serviced by a first VIOS to other VIOSes in the event of a VIOS cluster “split-brain” scenario generating a primary sub-cluster and a secondary sub-cluster, where the first VIOS is in the secondary sub-cluster. The VIOSes in the cluster continually exchange keep-alive information to provide each VIOS with an up-to-date status of other VIOSes within the cluster and to notify the VIOSes when one or more nodes loose connection to or are no longer communicating with other nodes within the cluster, as occurs with a cluster split-brain event / condition. When this event is detected, a first sub-cluster assumes a primary sub-cluster role and one or more clients served by one or more VIOSes within the secondary sub-cluster are autonomously migrated to other VIOSes in the primary sub-cluster, thus minimizing downtime for clients previously served by the unavailable / uncommunicative VIOSes.

Some embodiments provide a method for employing the management and control system of a network to dynamically recover from a split-brain condition in the edge nodes of the network. The method of some embodiments takes a corrective action to automatically recover from a split-brain failure occurred at a pair of high availability (HA) edge nodes of the network. The HA edge nodes include an active machine and a standby machine. The active edge node actively passes through the network traffic (e.g., north-south traffic for a logical network), while the standby edge node is synchronized and ready to transition to the active state, should a failure occur. Both HA nodes share the same configuration settings and only one is active until a path, link, or system failure occurs. The active edge node also provides stateful services (e.g., stateful firewall, load balancing, etc.) to the data compute nodes of the network.

Various embodiments are described herein that provide a network system comprising a set of peers within a link aggregation group (LAG), the first set of peers including a first network element and a second network element and a status resolution server to connect to the set of peers within the link aggregation group, wherein one or more peers within the LAG is to query the status resolution server to determine an operational status of a peer in the set of peers in response to detection of an apparent failure of the peer.

Systems, methods, apparatus and software can configure, support, and make use of a coordinator virtual device to determine which node or nodes of a cluster should be ejected from the cluster as a result of a cluster partition or other error event. Fencing software operating on the cluster nodes monitors the cluster for a cluster partition (split-brain) event, and when such an event occurs, software on the nodes attempts to gain control of the coordinator virtual device. A node that succeeds in gaining control of the coordinator virtual device survives. Nodes failing to gain control of the coordinator virtual device remove themselves or are removed from the cluster. The coordinator virtual device can be established by a virtual device configuration server which provides coordinator virtual device access to cluster nodes acting as virtual device configuration clients.

Systems and methods utilize an all-or-none switchover to prevent split-brain problems in a Multi-Chassis Link Aggregation Group (MC-LAG) network. A standby node in the MC-LAG network can perform the steps of remaining in a standby state responsive to a loss of adjacency with an active node, wherein, in the standby state, all standby links between the standby node and a common endpoint are non-distributing; monitoring frames transmitted by the common endpoint to the standby node over the standby links; and determining based on the monitoring frames whether all active links between the active node and the common endpoint have failed and entering an active state with all the standby links distributing based thereon.

A technique includes a set of procedures utilized during the transfer of service of a failed storage system to a surviving storage system of a cluster failover (CFO) configuration during a system outage, such as a disaster scenario. The procedures are executed by a RAID subsystem of the surviving storage system during disaster takeover, storage healing and node restart operations. The procedures prevent the possibility that clients accessing the storage system will see out-of-date versions of the data either during transfer of service of the system during the disaster scenario or subsequently after the storage system is healed and service on the failed system has been restored.

An apparatus and a method that prevent a split-brain problem by preventing a cluster partner from accessing and serving data when the cluster partner is taken over by a storage server, while allowing early release of reservations on the cluster partner's storage devices before control is given back to the cluster partner.

The invention discloses an arbitration server based cluster split-brain prevent method and device, and belongs to high-availability cluster split-brain prevention technology in the field of computer cluster technology, in order to solve the problem that services cannot be taken over or the services run on two nodes at the same time due to the fact that states of other nodes and running services thereof cannot be accurately distinguished when a cluster heartbeat network is interrupted. The scheme includes that when the heartbeat network is interrupted, cluster nodes not running services can take over the services only by acquiring corresponding service locks through an arbitration server so as to avoid the problem of split-brain; after the services cease, the arbitration server recovers the service locks and allows other cluster nodes to preempt the same again; in the process that multiple nodes preempt one service lock, only one node succeeds in preemption and the services can be started to prevent occurrence of the split-brain.

The invention provides two methods for preventing a brain from splitting of a cluster system. The first method is as follows: whether the brain is split is judged by detecting whether last two heartbeat cables are cut at the same time. The second method is as follows: whether the service is started at a node of the other side is judged by a ping floating IP method, thereby preventing the brain from splitting. The two methods can effectively avoid the brain splitting problem of the dual-computer high-useable cluster system, ensure that data is not damaged, and have the advantage that the support of any other hardware is not needed.

Various methods, systems, and processes to prevent data corruption caused by a pre-existing split brain condition in a cluster are presented. In response to determining that a node is no longer part of a sub-cluster, another node in the sub-cluster is designated as a racer node. The racer node accesses a matrix, and the matrix includes information to determine whether a majority of coordination points in a cluster are accessible by nodes in the sub-cluster. Based on the accessing, a determination is made that the information indicates that the majority of coordination points are accessible by the nodes. The information is then broadcasted.

A method, computer program product, and system for detecting and fencing off a failed entity instance so that failover time in the computing system is reduced. Upon detection of a failed entity, for example a failed process, a signal handler invokes an operating system interface to fence off the failed instance from modifying its persistent state, so that the entity may be re-instantiated prior to termination of the failed instance. This approach reduces failover time and eliminates split-brain problems without compromising access to the failed instance to obtain diagnostic information, core dumps, and the like.

Method and high availability clusters that support synchronous state replication to provide for failover between nodes, and more precisely, between the master candidate machines at the corresponding nodes. There are at least two master candidates (m=2) in the high availability cluster and the election of the current master is performed by a quorum-based majority vote among quorum machines, whose number n is at least three and odd (n≧3 and n is odd). The current master is issued a current time-limited lease to be measured off by the current master's local clock. In setting the duration or period of the lease, a relative clock skew is used to bound the duration to an upper bound, thus ensuring resistance to split brain situations during failover events.

The invention relates to a method and a device for solving dual-computer cluster split brain, belonging to the technical field of mass data storage. According to the method, one or more storage pools are created through a rear-end shared disk, the same storage pool can be assigned to a certain node according to user selection, a quorum disk for storing exchange information is created for each node in the storage pool, and the exchange information comprises a quorum superblock for identifying clusters and position and length of related information, a quorum information for identifying resource competing result and a response information for identifying that other nodes give up competition for the resource; when split brain happens, the node obtaining the resource writes quorum information into the quorum disk, which indicates that the resource of the node of the quorum disk is obtained by the node obtaining the resource; and the node obtaining no resource writes the response information into the quorum disk, which indicates that the node obtaining no resource knows that the resource of the node of the quorum disk is taken over by other node, and itself is going to give up competition for the resource. As compared with the prior art, by application of the method and the device provided by the invention, occurrence of split brain is avoided successfully.

The invention discloses a method for preventing a split brain phenomenon from occurring on a distributed replicated block device (DRBD) resource. According to the method, through modifying a OCF(Open Cluster Framework) script of a DRBD, the connection status and the network status of the DRBD resource are monitored; a node of a cluster is reversed before the split brain phenomenon occurs; data cannot be written into the reversed node during the stoppage period; and all data are written into another node, and thereby the occurrence of the split brain phenomenon of the DRBD is completely eradicated and the integrity of user data is protected.

The invention relates to a method and device for managing double active storage arrays. The method comprises the steps of counting the data amount received by a first storage array from a host; receiving the data amount sent by a second storage array of the data amount received by a second storage array from a host; making sure the data amount received by the first storage array from the host is less than the data amount received by the second storage array from the host; when making sure the link between the first storage array and the second storage array fails, sending an arbitrary request to an arbitrary server after delaying for a while, connecting the arbitrary server with the first storage array and the second storage array respectively, and receiving the arbitrary result sent by the arbitrary server; when making sure the link between the second storage array and the arbitrary server is disconnected, making sure the storage array which receives data through storage arrays; when in split-brain condition, storage arrays assigning the storage array which receives larger amount of data from the host to receive data from the host.

A method, data processing system, and computer program product autonomously migrate clients serviced by a first VIOS to other VIOSes in the event of a VIOS cluster “split-brain” scenario generating a primary sub-cluster and a secondary sub-cluster, where the first VIOS is in the secondary sub-cluster. The VIOSes in the cluster continually exchange keep-alive information to provide each VIOS with an up-to-date status of other VIOSes within the cluster and to notify the VIOSes when one or more nodes loose connection to or are no longer communicating with other nodes within the cluster, as occurs with a cluster split-brain event / condition. When this event is detected, a first sub-cluster assumes a primary sub-cluster role and one or more clients served by one or more VIOSes within the secondary sub-cluster are autonomously migrated to other VIOSes in the primary sub-cluster, thus minimizing downtime for clients previously served by the unavailable / uncommunicative VIOSes.

The invention discloses a data processing method. The data processing method comprises the following steps: first storage equipment receives a first reservation preemptive command sent by a host through a target port, wherein the first reservation preemptive command includes a port identifier of the target port, a reservation key to be checked and a LUN; a forwarding port corresponding to the target port is determined according to a pre-set port mapping relationship; the reservation key to be checked, the LUN, the port identifier of the target port and a port identifier of the forwarding port are encapsulated, so that a second reservation preemptive command is obtained; the second reservation preemptive command is sent to second storage equipment through the forwarding port; and the second storage equipment executes reservation preemptive operation according to the port identifier of the target port. The invention further provides related storage equipment for realizing the data processing method. By means of the data processing method and the related storage equipment disclosed by the invention, in a process in which different storage arrays implement online data migration, when a host cluster is subjected to split-brain, the data consistency among the different storage arrays is ensured; furthermore, the process is independent of a fibre channel switch; and thus, the application scene is relatively wide.

The present invention relates to a method, system and computer readable recording medium for determining a major group in a network split-brain situation that occurs in a network-based distributed computing environment. According to an aspect of the present invention, there is provided a method of determining a major group among at least two groups created by splitting an initial group consisting of a plurality of nodes in a network-based distributed environment, the method comprising the steps of comparing the number of nodes included in a first group with the number of nodes included in a second group; acquiring history information of the nodes included in the first and second groups; and determining whether the first group or the second group is the major group using at least one of a result of comparing the number of nodes and the history information.

The invention discloses a distributed cluster split-brain processing method, device and equipment. The method comprises the following steps: when the running state of the opposite side cannot be sensed between two mutually connected service clusters, switching the two service clusters into a read-only mode; determining at most one service cluster with the right to initiate voting according to theresult of whether the two service clusters and a database can be normally connected, wherein a service cluster with the voting right initiates voting to a preset voter set, and a service cluster whichdoes not have the right to initiate voting does not initiate voting; and if the service cluster that initiates voting within the preset time obtains the predetermined number of votes, switching the service cluster that initiates voting from the read-only mode to a normal service mode, and notifying the service cluster which does not initiate voting in the two clusters of a voting result, and stopping the work of the service cluster which does not initiate voting. Therefore, through the method disclosed by the invention, the occurrence of split-brain can be completely avoided, and the voting result is closer to the actual use condition.

A method implemented by a node in a high availability system having a master node and a replica node, the method including monitoring another node to determine whether or not the node is responding via a network connection, when the node is found to be not responding, changing into a periodic replication mode of operation, serving user requests while in the replication mode of operation, determining that the other node is now responding via the network connection, negotiating to merge changes resulting from serving the user requests with the other node, and reverting to an online replication mode of operation.

The invention discloses a database management method and device, a server and a storage medium. The method comprises the steps of obtaining opening records in system tables corresponding to at least two databases; compairing opening records in all the system tables according to preset fields, wherein the preset fields comprise a first identifier and a first sequence value, the first identifier isan identifier corresponding to the fact that the target database currently enters the opening state, and the first sequence value is a current log sequence value of the target database; and determining attributes of each database according to a comparison result of the opening records, wherein the attributes comprise at least one of a main database, a standby database and a split brain database. According to the technical scheme, the system table is used for recording the opening record of the main library; the standby database synchronizes the content of the main database system table by replaying the Redo log, and whether the data of each database is consistent or not is compared by comparing the opening records of the system table, so as to determine the attributes of the database, thereby accurately determining the main database, the standby database and the split brain database, and improving the stability of database operation.

The invention provides two methods for preventing a brain from splitting of a cluster system. The first method is as follows: whether the brain is split is judged by detecting whether last two heartbeat cables are cut at the same time. The second method is as follows: whether the service is started at a node of the other side is judged by a ping floating IP method, thereby preventing the brain from splitting. The two methods can effectively avoid the brain splitting problem of the dual-computer high-useable cluster system, ensure that data is not damaged, and have the advantage that the support of any other hardware is not needed.

The invention discloses a database management method and device, a server and a storage medium. The method comprises the steps of obtaining transition records in control files corresponding to at least two databases; comparing the transition records in the control files; and determining the attribute of each database according to the comparison result of the transition records, wherein the attribute comprises at least one of a main library, a standby library and a split brain library. According to the technical scheme, the control file is used for recording the transition records of all the databases, whether the data of all the databases are consistent or not can be compared by comparing the transition records, the attributes of the databases are determined based on the transition records, the purpose of accurately determining the main database, the standby database and the schizophrenia database is achieved, and the database operation stability is improved.

The embodiment of the invention relates to a cluster storage system and a split brain treatment method thereof. The system comprises a control channel interface module, a controller cluster module and a data channel interface module. The control channel interface module is used for controlling controllers in the controller cluster module to read and write corresponding discs in a disc case; the controller cluster module is used for reading and writing corresponding discs in the disc case under the control of the control channel interface module and exchanging data among the controllers in thecontroller cluster module via the data channel interface module; and the data channel interface module is used for providing data exchange channel for the controller cluster module under the control of the control channel interface module. The system and the split brain treatment method can help keep communication among the controllers in the controller cluster module when split brain happens in a heartbeat network.