NDB Cluster Configuration Files this parameter, and are made every 100 ms thereafter until connected. Once a data node has started, it can take up  HeartbeatIntervalDbApi  for the API node to be notified that this has occurred. API Node Debugging Parameters.   You can use the  ApiVerbose  configuration parameter to enable debugging output from a given API node. This parameter takes an integer value. 0 is the default, and disables such debugging; 1 enables debugging output to the cluster log; 2 adds  DBDICT  debugging output as well. (Bug #20638450) See also DUMP 1229. You can also obtain information from a MySQL server running as an NDB Cluster SQL node using  SHOW STATUS  in the  mysql  client, as shown here: For information about the status variables appearing in the output from this statement, see NDB Cluster Status Variables. To add new SQL or API nodes to the configuration of a running NDB Cluster, it is necessary to perform a rolling restart of all cluster nodes after adding new [mysqld]  or  [api]  sections to the  config.ini  file (or files, if you are using more than one management server). This must be done before the new SQL or API nodes can connect to the cluster. It is  not  necessary to perform any restart of the cluster if new SQL or API nodes can employ previously unused API slots in the cluster configuration to connect to the cluster. Restart types.   Information about the restart types used by the parameter descriptions in this section is shown in the following table: mysql>  SHOW STATUS LIKE ’ndb%’; +-----------------------------+----------------+ | Variable_name | Value | +-----------------------------+----------------+ | Ndb_cluster_node_id | 5 | | Ndb_config_from_host | 198.51.100.112 | | Ndb_config_from_port | 1186 | | Ndb_number_of_storage_nodes | 4 | +-----------------------------+----------------+ 4 rows in set (0.02 sec) Note Table 23.18 NDB Cluster restart types Symbol Restart Type Description N Node The parameter can be updated using a rolling restart (see Section 23.5.5, “Performing a Rolling Restart of an NDB Cluster” ) S System All cluster nodes must be shut down completely, then restarted, to effect a change in this parameter I Initial Data nodes must be restarted using the  --initial  option 4159