Overview of NDB Cluster Configuration Parameters, Options, and Variables To check that your nodes were set up properly, start the management client: ndb_mgm>  SHOW Cluster Configuration --------------------- [ndbd(NDB)] 1 node(s) id=2 @127.0.0.1 (Version: 8.0.26-ndb-8.0.26, Nodegroup: 0, *) [ndb_mgmd(MGM)] 1 node(s) id=1 @127.0.0.1 (Version: 8.0.26-ndb-8.0.26) [mysqld(API)] 3 node(s) id=3 @127.0.0.1 (Version: 8.0.26-ndb-8.0.26) id=4 (not connected, accepting connect from any host) id=5 (not connected, accepting connect from any host) shell>  ndb_mgm Use the  SHOW  command from within the management client to obtain a report on the cluster’s status: At this point, you have successfully set up a working NDB Cluster . You can now store data in the cluster by using any table created with  ENGINE=NDBCLUSTER  or its alias  ENGINE=NDB . 23.3.2 Overview of NDB Cluster Configuration Parameters, Options, and Variables The next several sections provide summary tables of NDB Cluster node configuration parameters used in the  config.ini  file to govern various aspects of node behavior, as well as of options and variables read by  mysqld  from a  my.cnf  file or from the command line when run as an NDB Cluster process. Each of the node parameter tables lists the parameters for a given type ( ndbd ,  ndb_mgmd ,  mysqld ,  computer , tcp , or  shm ). All tables include the data type for the parameter, option, or variable, as well as its default, mimimum, and maximum values as applicable. Considerations when restarting nodes.   For node parameters, these tables also indicate what type of restart is required (node restart or system restart)—and whether the restart must be done with  -- initial —to change the value of a given configuration parameter. When performing a node restart or an initial node restart, all of the cluster’s data nodes must be restarted in turn (also referred to as a  rolling restart ). It is possible to update cluster configuration parameters marked as  node  online—that is, without shutting down the cluster—in this fashion. An initial node restart requires restarting each  ndbd  process with the  --initial  option. A system restart requires a complete shutdown and restart of the entire cluster. An initial system restart requires taking a backup of the cluster, wiping the cluster file system after shutdown, and then restoring from the backup following the restart. In any cluster restart, all of the cluster’s management servers must be restarted for them to read the updated configuration parameter values. Values for numeric cluster parameters can generally be increased without any problems, although it is advisable to do so progressively, making such adjustments in relatively small increments. Many of these can be increased online, using a rolling restart. However, decreasing the values of such parameters—whether this is done using a node restart, node initial restart, or even a complete system restart of the cluster—is not to be undertaken lightly; it is recommended that you do so only 4031 Important