Disclosed are systems and methods for leader node election, comprising a cluster system including a plurality of nodes, a node registry, wherein nodes are configured to transmit registration requests to the node registry, receive node data is response, and to determine a leader node based on the earliest registered node, and wherein the leader node is configured to dynamically allocate data slots between the plurality of nodes, and each of the nodes are configured to store data associated with allocated data slots in an in-memory least recently used component and data associated with all of the data slots in a persistent storage component.

In a running distributed data storage system that actively processes I/Os, metadata nodes are commissioned and decommissioned without taking down the storage system and without introducing interruptions to metadata or payload data I/O. The inflow of reads and writes continues without interruption even while new metadata nodes are in the process of being added and/or removed and the strong consistency of the system is guaranteed. Commissioning and decommissioning nodes within the running system enables streamlined replacement of permanently failed nodes and advantageously enables the system to adapt elastically to workload changes. An illustrative distributed barrier logic (the “view change barrier”) controls a multi-state process that controls a coordinated step-wise progression of the metadata nodes from an old view to a new normal. Rules for I/O handling govern each state until the state machine loop has been traversed and the system reaches its new normal.

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Methods, systems and computer program products for maintaining components of networked nodes with distributed data dependencies are described. For example, in accordance with one or more embodiments, a method can comprise identifying, by a device comprising a processor, in a group of dependent nodes of a cluster of nodes, a first portion of the dependent nodes for which an update is implicated. The method can further comprise selecting, by the device, from the first portion, a second portion of the dependent nodes that are predicted to be able to be updated with the update without affecting access to data of the group of dependent nodes. Further, the method can comprise communicating, by the device, the update to the second portion of the dependent nodes.

Techniques for load balancing and fault tolerant service are described. An apparatus may comprise load balancing and fault tolerant component operative to execute a load balancing and fault tolerant service in a distributed data system. The load balancing and fault tolerant service distributes a load of a task to a first node in a cluster of nodes using a routing table. The load balancing and fault tolerant service stores information to indicate the first node from the cluster of nodes is assigned to perform the task. The load balancing and fault tolerant service detects a failure condition for the first node. The load balancing and fault tolerant service moves the task to a second node from the cluster of nodes to perform the task for the first node upon occurrence of the failure condition.

A method for failure detection and role selection for a process in a network of redundant processes including a primary process configured to transmit a heartbeat signal with a predetermined interval to the processes of the network.

Techniques for load balancing and fault tolerant service are described. An apparatus may comprise load balancing and fault tolerant component operative to execute a load balancing and fault tolerant service in a distributed data system. The load balancing and fault tolerant service distributes a load of a task to a first node in a cluster of nodes using a routing table. The load balancing and fault tolerant service stores information to indicate the first node from the cluster of nodes is assigned to perform the task. The load balancing and fault tolerant service detects a failure condition for the first node. The load balancing and fault tolerant service moves the task to a second node from the cluster of nodes to perform the task for the first node upon occurrence of the failure condition.

Systems and methods for managing a highly available distributed database comprising: a memory storing instructions; and one or more processors configured to execute the instructions to: determine that a source node, in a distributed database comprising the source node and one or more replica nodes, is not available; select a most-updated replica node from the one or more replica nodes; switch a role of the most-updated replica node to source; update a data store to label the source node as unavailable and the selected replica node as being a promoted source node; send a notification to a user device to update a database topology based on the updated data store; determine whether the user device has updated the database topology; and upon determining the user device has not updated the database topology, continue to send the notification to the user device until the user device has updated the database topology.

A method, computer program product, and computing system for receiving, at a first baseboard management controller (BMC) of a first node, a fence request from a central processing unit (CPU) of the first node. The first BMC of the first node may communicate with a second BMC of a second node, wherein the first node and the second node are communicatively coupled to a plurality of storage drives. The first BMC and the second BMC may determine which node of the first node and the second node to fence from the plurality of storage drives. One of the first node and the second node may be fenced, via one of the first BMC and the second BMC, from the plurality of storage drives, thus defining a fenced node.

A method for failure detection and role selection for a process in a network of redundant processes including a primary process configured to transmit a heartbeat signal with a predetermined interval to the processes of the network.