NDB Cluster Log Messages Log Message Description Event Name Event Type Priority Severity has failed. The Node state at failure was state_code is described by an arbitration state code state_code : possible state code values can be found in the file  include/ kernel/ signaldata/ ArbitSignalData.hpp . President restarts arbitration thread [state= state_code ] or  Prepare arbitrator node  node_id [ticket= ticket_id ] or  Receive arbitrator node  node_id [ticket= ticket_id ] or  Started arbitrator node  node_id [ticket= ticket_id ] or  Lost arbitrator node  node_id - process failure [state= state_code ] or  Lost arbitrator node node_id  - process exit [state= state_code ] or  Lost arbitrator node node_id  - error_message [state= state_code ] This is a report on the current state and progress of arbitration in the cluster. node_id  is the node ID of the management node or SQL node selected as the arbitrator. state_code is an arbitration state code, as found in include/ kernel/ signaldata/ ArbitSignalData.hpp . When an error has occurred, an error_message , also defined in ArbitSignalData.hpp , is provided. ticket_id is a unique identifier handed out by the arbitrator when it is selected to all the nodes that participated in its selection; this is used to ensure that each node requesting arbitration was one of the nodes that took part ArbitState NodeRestart 6 INFO 4452