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ndb_ node_id _trace.log. trace_id _t thread_id , 

In this pattern, node_id  stands for the data node’s unique node ID in the cluster, trace_id is a trace sequence number, and thread_id  is the thread ID. For example, in the event of the failure of an ndbmtd  process running as an NDB Cluster data node having the node ID 3 and with MaxNoOfExecutionThreads  equal to 4, four trace files are generated in the data node’s data directory. If the is the first time this node has failed, then these files are named ndb_3_trace.log.1_t1 , ndb_3_trace.log.1_t2 , ndb_3_trace.log.1_t3 , and ndb_3_trace.log.1_t4 . Internally, these trace files follow the same format as ndbd  trace files. 

The ndbd  exit codes and messages that are generated when a data node process shuts down prematurely are also used by ndbmtd . See Data Node Error Messages, for a listing of these. 

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## Note 

It is possible to use ndbd  and ndbmtd  concurrently on different data nodes in the same NDB Cluster. However, such configurations have not been tested extensively; thus, we cannot recommend doing so in a production setting at this time. 

## 23.4.4 ndb_mgmd — The NDB Cluster Management Server Daemon 

The management server is the process that reads the cluster configuration file and distributes this information to all nodes in the cluster that request it. It also maintains a log of cluster activities. Management clients can connect to the management server and check the cluster’s status. 

All options that can be used with ndb_mgmd  are shown in the following table. Additional descriptions follow the table. 

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