3.4 MGM API Data Structures

The ndb_logevent Structure

Description: This structure models a Cluster log event, and is used for storing and retrieving log event information.

Definition. ndb_logevent has 8 members, the first 7 of which are shown in the following list:

void* handle: An NdbLogEventHandle, set by ndb_logevent_get_next(). This handle is used only for purposes of comparison.
type: Tells which type of event (Ndb_logevent_type) this is.
unsigned time: The time at which the log event was registered with the management server.
category: The log event category (ndb_mgm_event_category).
severity: The log event severity (ndb_mgm_event_severity).
unsigned level: The log event level. This is a value in the range of 0 to 15, inclusive.
unsigned source_nodeid: The node ID of the node that reported this event.

The 8^th member of this structure contains data specific to the log event, and is dependent on its type. It is defined as the union of a number of data structures, each corresponding to a log event type. Which structure to use is determined by the value of type, and is shown in the following table:

Table 3.7 Type Ndb_logevent_type values and structures used

`Ndb_logevent_type` Value	Structure
`NDB_LE_Connected`	`Connected`: unsigned `node`
`NDB_LE_Disconnected`	`Disconnected`: unsigned `node`
`NDB_LE_CommunicationClosed`	`CommunicationClosed`: unsigned `node`
`NDB_LE_CommunicationOpened`	`CommunicationOpened`: unsigned `node`
`NDB_LE_ConnectedApiVersion`	`ConnectedApiVersion`: unsigned `node` unsigned `version`
`NDB_LE_GlobalCheckpointStarted`	`GlobalCheckpointStarted`: unsigned `gci`
`NDB_LE_GlobalCheckpointCompleted`	`GlobalCheckpointCompleted`: unsigned `gci`
`NDB_LE_LocalCheckpointStarted`	`LocalCheckpointStarted`: unsigned `lci` unsigned `keep_gci` unsigned `restore_gci`
`NDB_LE_LocalCheckpointCompleted`	`LocalCheckpointCompleted`: unsigned `lci`
`NDB_LE_LCPStoppedInCalcKeepGci`	`LCPStoppedInCalcKeepGci`: unsigned `data`
`NDB_LE_LCPFragmentCompleted`	`LCPFragmentCompleted`: unsigned `node` unsigned `table_id` unsigned `fragment_id`
`NDB_LE_UndoLogBlocked`	`UndoLogBlocked`: unsigned `acc_count` unsigned `tup_count`
`NDB_LE_NDBStartStarted`	`NDBStartStarted`: unsigned `version`
`NDB_LE_NDBStartCompleted`	`NDBStartCompleted`: unsigned `version`
`NDB_LE_STTORRYRecieved`	`STTORRYRecieved`: [NONE]
`NDB_LE_StartPhaseCompleted`	`StartPhaseCompleted`: unsigned `phase` unsigned `starttype`
`NDB_LE_CM_REGCONF`	`CM_REGCONF`: unsigned `own_id` unsigned `president_id` unsigned `dynamic_id`
`NDB_LE_CM_REGREF`	`CM_REGREF`: unsigned `own_id` unsigned `other_id` unsigned `cause`
`NDB_LE_FIND_NEIGHBOURS`	`FIND_NEIGHBOURS`: unsigned `own_id` unsigned `left_id` unsigned `right_id` unsigned `dynamic_id`
`NDB_LE_NDBStopStarted`	`NDBStopStarted`: unsigned `stoptype`
`NDB_LE_NDBStopCompleted`	`NDBStopCompleted`: unsigned `action` unsigned `signum`
`NDB_LE_NDBStopForced`	`NDBStopForced`: unsigned `action` unsigned `signum` unsigned `error` unsigned `sphase` unsigned `extra`
`NDB_LE_NDBStopAborted`	`NDBStopAborted`: [NONE]
`NDB_LE_StartREDOLog`	`StartREDOLog`: unsigned `node` unsigned `keep_gci` unsigned `completed_gci` unsigned `restorable_gci`
`NDB_LE_StartLog`	`StartLog`: unsigned `log_part` unsigned `start_mb` unsigned `stop_mb` unsigned `gci`
`NDB_LE_UNDORecordsExecuted`	`UNDORecordsExecuted`: unsigned `block` unsigned `data1` unsigned `data2` unsigned `data3` unsigned `data4` unsigned `data5` unsigned `data6` unsigned `data7` unsigned `data8` unsigned `data9` unsigned `data10`
`NDB_LE_NR_CopyDict`	`NR_CopyDict`: [NONE]
`NDB_LE_NR_CopyDistr`	`NR_CopyDistr`: [NONE]
`NDB_LE_NR_CopyFragsStarted`	`NR_CopyFragsStarted`: unsigned `dest_node`
`NDB_LE_NR_CopyFragDone`	`NR_CopyFragDone`: unsigned `dest_node` unsigned `table_id` unsigned `fragment_id`
`NDB_LE_NR_CopyFragsCompleted`	`NR_CopyFragsCompleted`: unsigned `dest_node`
`NDB_LE_NodeFailCompleted`	`NodeFailCompleted`: unsigned `block` unsigned `failed_node` unsigned `completing_node` (For `block` and `completing_node`, `0` is interpreted as “all”.)
`NDB_LE_NODE_FAILREP`	`NODE_FAILREP`: unsigned `failed_node` unsigned `failure_state`
`NDB_LE_ArbitState`	`ArbitState`: unsigned `code` unsigned `arbit_node` unsigned `ticket_0` unsigned `ticket_1`
`NDB_LE_ArbitResult`	`ArbitResult`: unsigned `code` unsigned `arbit_node` unsigned `ticket_0` unsigned `ticket_1`
`NDB_LE_GCP_TakeoverStarted`	`GCP_TakeoverStarted`: [NONE]
`NDB_LE_GCP_TakeoverCompleted`	`GCP_TakeoverCompleted`: [NONE]
`NDB_LE_LCP_TakeoverStarted`	`LCP_TakeoverStarted`: [NONE]
`NDB_LE_TransReportCounters`	`TransReportCounters`: unsigned `trans_count` unsigned `commit_count` unsigned `read_count` unsigned `simple_read_count` unsigned `write_count` unsigned `attrinfo_count` unsigned `conc_op_count` unsigned `abort_count` unsigned `scan_count` unsigned `range_scan_count`
`NDB_LE_OperationReportCounters`	`OperationReportCounters`: unsigned `ops`
`NDB_LE_TableCreated`	`TableCreated`: unsigned `table_id`
`NDB_LE_JobStatistic`	`JobStatistic`: unsigned `mean_loop_count`
`NDB_LE_SendBytesStatistic`	`SendBytesStatistic`: unsigned `to_node` unsigned `mean_sent_bytes`
`NDB_LE_ReceiveBytesStatistic`	`ReceiveBytesStatistic`: unsigned `from_node` unsigned `mean_received_bytes`
`NDB_LE_MemoryUsage`	`MemoryUsage`: int `gth` unsigned `page_size_kb` unsigned `pages_used` unsigned `pages_total` unsigned `block`
`NDB_LE_TransporterError`	`TransporterError`: unsigned `to_node` unsigned `code`
`NDB_LE_TransporterWarning`	`TransporterWarning`: unsigned `to_node` unsigned `code`
`NDB_LE_MissedHeartbeat`	`MissedHeartbeat`: unsigned `node` unsigned `count`
`NDB_LE_DeadDueToHeartbeat`	`DeadDueToHeartbeat`: unsigned `node`
`NDB_LE_WarningEvent`	`WarningEvent`: [NOT YET IMPLEMENTED]
`NDB_LE_SentHeartbeat`	`SentHeartbeat`: unsigned `node`
`NDB_LE_CreateLogBytes`	`CreateLogBytes`: unsigned `node`
`NDB_LE_InfoEvent`	`InfoEvent`: [NOT YET IMPLEMENTED]
`NDB_LE_EventBufferStatus` (Prior to NDB 7.5)	`EventBufferStatus:`: unsigned `usage` unsigned `alloc` unsigned `max` unsigned `apply_gci_l` unsigned `apply_gci_h` unsigned `latest_gci_l` unsigned `latest_gci_h`
`NDB_LE_EventBufferStatus2` (NDB 7.5)	`EventBufferStatus2`: unsigned `usage` unsigned `alloc` unsigned `max` unsigned `latest_consumed_epoch_l` unsigned `latest_consumed_epoch_h` unsigned `latest_buffered_epoch_l` unsigned `latest_buffered_epoch_h` unsigned `ndb_reference` unsigned `report_reason` `report_reason` is one of `NO_REPORT`, `COMPLETELY_BUFFERING`, `PARTIALLY_DISCARDING`, `COMPLETELY_DISCARDING`, `PARTIALLY_BUFFERING`, `BUFFERED_EPOCHS_OVER_THRESHOLD`, `ENOUGH_FREE_EVENTBUFFER`, or `LOW_FREE_EVENTBUFFER`; see Event Buffer Reporting in the Cluster Log, for descriptions of these values
`NDB_LE_BackupStarted`	`BackupStarted`: unsigned `starting_node` unsigned `backup_id`
`NDB_LE_BackupFailedToStart`	`BackupFailedToStart`: unsigned `starting_node` unsigned `error`
`NDB_LE_BackupCompleted`	`BackupCompleted`: unsigned `starting_node` unsigned `backup_id` unsigned `start_gci` unsigned `stop_gci` unsigned `n_records` unsigned `n_log_records` unsigned `n_bytes` unsigned `n_log_bytes`
`NDB_LE_BackupAborted`	`BackupAborted`: unsigned `starting_node` unsigned `backup_id` unsigned `error`
`NDB_LE_SingleUser`	`SingleUser`: unsigned `type` unsigned `node_id`
`NDB_LE_StartReport`	`StartReport`: unsigned `report_type` unsigned `remaining_time` unsigned `bitmask_size` unsigned `bitmask_data[1]`

The ndb_mgm_node_state Structure

Description: Provides information on the status of a Cluster node.

Definition. This structure contains the following members:

int node_id: The cluster node's node ID.
enum ndb_mgm_node_type node_type: The node type.
See The ndb_mgm_node_type Type, for permitted values.
enum ndb_mgm_node_status node_status: The node's status.
See The ndb_mgm_node_status Type, for permitted values.
int start_phase: The start phase.
This is valid only if the node_type is NDB_MGM_NODE_TYPE_NDB and the node_status is NDB_MGM_NODE_STATUS_STARTING.
int dynamic_id: The ID for heartbeats and master takeover.
Valid only for data (ndbd) nodes.
int node_group: The node group to which the node belongs.
Valid only for data (ndbd) nodes.
int version: Internal version number.
int connect_count: The number of times this node has connected to or disconnected from the management server.
char connect_address[]: The IP address of this node as seen by the other nodes in the cluster.
int mysql_version: The MySQL version number, expressed as an integer (for example: 80200). Applies only to SQL nodes.
int is_single_user: The node ID of the API or SQL node having exclusive access when the cluster is in single user mode. Does not otherwise apply. Added in NDB 8.0.

The ndb_mgm_node_state2 Structure

Description: Provides information on the status of a Cluster node.

Definition. This structure contains the following members:

int node_id: The cluster node's node ID.
enum ndb_mgm_node_type node_type: The node type.
See The ndb_mgm_node_type Type, for permitted values.
enum ndb_mgm_node_status node_status: The node's status.
See The ndb_mgm_node_status Type, for permitted values.
int start_phase: The start phase.
This is valid only if the node_type is NDB_MGM_NODE_TYPE_NDB and the node_status is NDB_MGM_NODE_STATUS_STARTING.
int dynamic_id: The ID for heartbeats and master takeover.
Valid only for data (ndbd) nodes.
int node_group: The node group to which the node belongs.
Valid only for data (ndbd) nodes.
int version: Internal version number.
int connect_count: The number of times this node has connected to or disconnected from the management server.
int mysql_version: The MySQL version number, expressed as an integer (for example: 80200). Applies only to SQL nodes.
int is_single_user: The node ID of the API or SQL node having exclusive access when the cluster is in single user mode. Does not otherwise apply.
char connect_address[]: The IP address of this node as seen by the other nodes in the cluster.

The ndb_mgm_cluster_state Structure

Description: Provides information on the status of all Cluster nodes. This structure is returned by ndb_mgm_get_status().

Definition. This structure has the following two members:

int no_of_nodes: The number of elements in the node_states array.
struct ndb_mgm_node_state node_states[]: An array containing the states of the nodes.
Each element of this array is an ndb_mgm_node_state structure.

See ndb_mgm_get_status().

The ndb_mgm_cluster_state2 Structure

Description: Provides information on the status of all Cluster nodes. This structure is returned by ndb_mgm_get_status3(), and was added in NDB 8.0.

Definition. This structure has the following two members:

int no_of_nodes: The number of elements in the node_states array.
struct ndb_mgm_node_state2 node_states[]: An array containing the states of the nodes.
Each element of this array is an ndb_mgm_node_state2 structure.

See ndb_mgm_get_status3().

The ndb_mgm_reply Structure

Description: Contains response information, consisting of a response code and a corresponding message, from the management server.

Definition. This structure contains two members, as shown here:

int return_code: For a successful operation, this value is 0; otherwise, it contains an error code.
For error codes, see The ndb_mgm_error Type.
char message[256]: contains the text of the response or error message.

See ndb_mgm_get_latest_error(), and ndb_mgm_get_latest_error_msg().