NDB Cluster Configuration Files The  [ndbd]  and  [ndbd default]  sections are used to configure the behavior of the cluster’s data nodes. [ndbd]  and  [ndbd default]  are always used as the section names whether you are using  ndbd  or ndbmtd  binaries for the data node processes. There are many parameters which control buffer sizes, pool sizes, timeouts, and so forth. The only mandatory parameter is either one of  ExecuteOnComputer  or  HostName ; this must be defined in the local  [ndbd]  section. The parameter  NoOfReplicas  should be defined in the  [ndbd default]  section, as it is common to all Cluster data nodes. It is not strictly necessary to set  NoOfReplicas , but it is good practice to set it explicitly. Most data node parameters are set in the  [ndbd default]  section. Only those parameters explicitly stated as being able to set local values are permitted to be changed in the  [ndbd]  section. Where present,  HostName ,  NodeId  and  ExecuteOnComputer must  be defined in the local  [ndbd]  section, and not in any other section of  config.ini . In other words, settings for these parameters are specific to one data node. For those parameters affecting memory usage or buffer sizes, it is possible to use  K ,  M , or  G  as a suffix to indicate units of 1024, 1024×1024, or 1024×1024×1024. (For example,  100K  means 100 × 1024 = 102400.) Parameter names and values are case-insensitive, unless used in a MySQL Server  my.cnf  or  my.ini file, in which case they are case-sensitive. Information about configuration parameters specific to NDB Cluster Disk Data tables can be found later in this section (see Disk Data Configuration Parameters). All of these parameters also apply to  ndbmtd  (the multithreaded version of  ndbd ). Three additional data node configuration parameters— MaxNoOfExecutionThreads ,  ThreadConfig , and NoOfFragmentLogParts —apply to  ndbmtd  only; these have no effect when used with  ndbd . For more information, see Multi-Threading Configuration Parameters (ndbmtd). See also Section 23.4.3, “ndbmtd — The NDB Cluster Data Node Daemon (Multi-Threaded)” . Identifying data nodes.   The  NodeId  or  Id  value (that is, the data node identifier) can be allocated on the command line when the node is started or in the configuration file. • NodeId A unique node ID is used as the node’s address for all cluster internal messages. For data nodes, this is an integer in the range 1 to 144 inclusive. (In NDB 8.0.17 and earlier, this was 1 to 48 inclusive.) Each node in the cluster must have a unique identifier. Version (or later) NDB 8.0.13 Type or units unsigned Default [...] Range 1 - 48 Version (or later) NDB 8.0.18 Type or units unsigned Default [...] Range 1 - 144 Restart Type IS (NDB 8.0.13) 4069