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Info (Zip) - 4.0Mb NDB Cluster Log Events

An event report reported in the event logs has the following format:

datetime [string] severity -- message

For example:

09:19:30 2005-07-24 [NDB] INFO -- Node 4 Start phase 4 completed

This section discusses all reportable events, ordered by category and severity level within each category.

In the event descriptions, GCP and LCP mean Global Checkpoint and Local Checkpoint, respectively.


These events are associated with connections between Cluster nodes.

Table 25.28 Events associated with connections between cluster nodes

Event Priority Severity Level Description
Connected 8 INFO Data nodes connected
Disconnected 8 ALERT Data nodes disconnected
CommunicationClosed 8 INFO SQL node or data node connection closed
CommunicationOpened 8 INFO SQL node or data node connection open
ConnectedApiVersion 8 INFO Connection using API version


The logging messages shown here are associated with checkpoints.

Table 25.29 Events associated with checkpoints

Event Priority Severity Level Description
GlobalCheckpointStarted 9 INFO Start of GCP: REDO log is written to disk
GlobalCheckpointCompleted 10 INFO GCP finished
LocalCheckpointStarted 7 INFO Start of LCP: data written to disk
LocalCheckpointCompleted 7 INFO LCP completed normally
LCPStoppedInCalcKeepGci 0 ALERT LCP stopped
LCPFragmentCompleted 11 INFO LCP on a fragment has been completed
UndoLogBlocked 7 INFO UNDO logging blocked; buffer near overflow
RedoStatus 7 INFO Redo status


The following events are generated in response to the startup of a node or of the cluster and of its success or failure. They also provide information relating to the progress of the startup process, including information concerning logging activities.

Table 25.30 Events relating to the startup of a node or cluster

Event Priority Severity Level Description
NDBStartStarted 1 INFO Data node start phases initiated (all nodes starting)
NDBStartCompleted 1 INFO Start phases completed, all data nodes
STTORRYRecieved 15 INFO Blocks received after completion of restart
StartPhaseCompleted 4 INFO Data node start phase X completed
CM_REGCONF 3 INFO Node has been successfully included into the cluster; shows the node, managing node, and dynamic ID
CM_REGREF 8 INFO Node has been refused for inclusion in the cluster; cannot be included in cluster due to misconfiguration, inability to establish communication, or other problem
FIND_NEIGHBOURS 8 INFO Shows neighboring data nodes
NDBStopStarted 1 INFO Data node shutdown initiated
NDBStopCompleted 1 INFO Data node shutdown complete
NDBStopForced 1 ALERT Forced shutdown of data node
NDBStopAborted 1 INFO Unable to shut down data node normally
StartREDOLog 4 INFO New redo log started; GCI keep X, newest restorable GCI Y
StartLog 10 INFO New log started; log part X, start MB Y, stop MB Z
UNDORecordsExecuted 15 INFO Undo records executed
StartReport 4 INFO Report started
LogFileInitStatus 7 INFO Log file initialization status
LogFileInitCompStatus 7 INFO Log file completion status
StartReadLCP 10 INFO Start read for local checkpoint
ReadLCPComplete 10 INFO Read for local checkpoint completed
RunRedo 8 INFO Running the redo log
RebuildIndex 10 INFO Rebuilding indexes


The following events are generated when restarting a node and relate to the success or failure of the node restart process.

Table 25.31 Events relating to restarting a node

Event Priority Severity Level Description
NR_CopyDict 7 INFO Completed copying of dictionary information
NR_CopyDistr 7 INFO Completed copying distribution information
NR_CopyFragsStarted 7 INFO Starting to copy fragments
NR_CopyFragDone 10 INFO Completed copying a fragment
NR_CopyFragsCompleted 7 INFO Completed copying all fragments
NodeFailCompleted 8 ALERT Node failure phase completed
NODE_FAILREP 8 ALERT Reports that a node has failed
ArbitState 6 INFO Report whether an arbitrator is found or not; there are seven different possible outcomes when seeking an arbitrator, listed here:
  • Management server restarts arbitration thread [state=X]

  • Prepare arbitrator node X [ticket=Y]

  • Receive arbitrator node X [ticket=Y]

  • Started arbitrator node X [ticket=Y]

  • Lost arbitrator node X - process failure [state=Y]

  • Lost arbitrator node X - process exit [state=Y]

  • Lost arbitrator node X <error msg> [state=Y]

ArbitResult 2 ALERT Report arbitrator results; there are eight different possible results for arbitration attempts, listed here:
  • Arbitration check failed: less than 1/2 nodes left

  • Arbitration check succeeded: node group majority

  • Arbitration check failed: missing node group

  • Network partitioning: arbitration required

  • Arbitration succeeded: affirmative response from node X

  • Arbitration failed: negative response from node X

  • Network partitioning: no arbitrator available

  • Network partitioning: no arbitrator configured

GCP_TakeoverStarted 7 INFO GCP takeover started
GCP_TakeoverCompleted 7 INFO GCP takeover complete
LCP_TakeoverStarted 7 INFO LCP takeover started
LCP_TakeoverCompleted 7 INFO LCP takeover complete (state = X)
ConnectCheckStarted 6 INFO Connection check started
ConnectCheckCompleted 6 INFO Connection check completed
NodeFailRejected 6 ALERT Node failure phase failed


The following events are of a statistical nature. They provide information such as numbers of transactions and other operations, amount of data sent or received by individual nodes, and memory usage.

Table 25.32 Events of a statistical nature

Event Priority Severity Level Description
TransReportCounters 8 INFO Report transaction statistics, including numbers of transactions, commits, reads, simple reads, writes, concurrent operations, attribute information, and aborts
OperationReportCounters 8 INFO Number of operations
TableCreated 7 INFO Report number of tables created
JobStatistic 9 INFO Mean internal job scheduling statistics
ThreadConfigLoop 9 INFO Number of thread configuration loops
SendBytesStatistic 9 INFO Mean number of bytes sent to node X
ReceiveBytesStatistic 9 INFO Mean number of bytes received from node X
MemoryUsage 5 INFO Data and index memory usage (80%, 90%, and 100%)
MTSignalStatistics 9 INFO Multithreaded signals


These events relate to NDB Cluster schema operations.

Table 25.33 Events relating to NDB Cluster schema operations

Event Priority Severity Level Description
CreateSchemaObject 8 INFO Schema objected created
AlterSchemaObject 8 INFO Schema object updated
DropSchemaObject 8 INFO Schema object dropped

ERROR Events

These events relate to Cluster errors and warnings. The presence of one or more of these generally indicates that a major malfunction or failure has occurred.

Table 25.34 Events relating to cluster errors and warnings

Event Priority Severity Level Description
TransporterError 2 ERROR Transporter error
TransporterWarning 8 WARNING Transporter warning
MissedHeartbeat 8 WARNING Node X missed heartbeat number Y
DeadDueToHeartbeat 8 ALERT Node X declared dead due to missed heartbeat
WarningEvent 2 WARNING General warning event
SubscriptionStatus 4 WARNING Change in subscription status

INFO Events

These events provide general information about the state of the cluster and activities associated with Cluster maintenance, such as logging and heartbeat transmission.

Table 25.35 Information events

Event Priority Severity Level Description
SentHeartbeat 12 INFO Sent heartbeat
CreateLogBytes 11 INFO Create log: Log part, log file, size in MB
InfoEvent 2 INFO General informational event
EventBufferStatus 7 INFO Event buffer status
EventBufferStatus2 7 INFO Improved event buffer status information


SentHeartbeat events are available only if NDB Cluster was compiled with VM_TRACE enabled.


These events are associated with entering and exiting single user mode.

Table 25.36 Events relating to single user mode

Event Priority Severity Level Description
SingleUser 7 INFO Entering or exiting single user mode


These events provide information about backups being created or restored.

Table 25.37 Backup events

Event Priority Severity Level Description
BackupStarted 7 INFO Backup started
BackupStatus 7 INFO Backup status
BackupCompleted 7 INFO Backup completed
BackupFailedToStart 7 ALERT Backup failed to start
BackupAborted 7 ALERT Backup aborted by user
RestoreStarted 7 INFO Started restoring from backup
RestoreMetaData 7 INFO Restoring metadata
RestoreData 7 INFO Restoring data
RestoreLog 7 INFO Restoring log files
RestoreCompleted 7 INFO Completed restoring from backup
SavedEvent 7 INFO Event saved