Adding NDB Cluster Data Nodes Online 2. Because shutting down the management server causes the management client to terminate, you must start the management server from the system shell. For simplicity, we assume that  config.ini  is in the same directory as the management server binary, but in practice, you must supply the correct path to the configuration file. You must also supply the  --reload  or  --initial  option so that the management server reads the new configuration from the file rather than its configuration cache. If your shell’s current directory is also the same as the directory where the management server binary is located, then you can invoke the management server as shown here: shell>  ndb_mgmd -f config.ini --reload 2008-12-08 17:29:23 [MgmSrvr] INFO -- NDB Cluster Management Server. 8.0.26-ndb-8.0.26 2008-12-08 17:29:23 [MgmSrvr] INFO -- Reading cluster configuration from ’config.ini’ -- NDB Cluster -- Management Client -- ndb_mgm>  SHOW Connected to Management Server at: 198.51.100.10:1186 Cluster Configuration --------------------- [ndbd(NDB)] 2 node(s) id=1 @198.51.100.1 (8.0.26-ndb-8.0.26, Nodegroup: 0, *) id=2 @198.51.100.2 (8.0.26-ndb-8.0.26, Nodegroup: 0) id=3 (not connected, accepting connect from 198.51.100.3) id=4 (not connected, accepting connect from 198.51.100.4) [ndb_mgmd(MGM)] 1 node(s) id=10 @198.51.100.10 (8.0.26-ndb-8.0.26) [mysqld(API)] 2 node(s) id=20 @198.51.100.20 (8.0.26-ndb-8.0.26) id=21 @198.51.100.21 (8.0.26-ndb-8.0.26) ndb_mgm>  1 RESTART Node 1: Node shutdown initiated Node 1: Node shutdown completed, restarting, no start. Node 1 is being restarted ndb_mgm> Node 1: Start initiated (version 8.0.26) Node 1: Started (version 8.0.26) ndb_mgm>  2 RESTART Node 2: Node shutdown initiated Node 2: Node shutdown completed, restarting, no start. Node 2 is being restarted ndb_mgm> Node 2: Start initiated (version 8.0.26) ndb_mgm> Node 2: Started (version 8.0.26) If you check the output of  SHOW  in the management client after restarting the  ndb_mgm  process, you should now see something like this: Step 3: Perform a rolling restart of the existing data nodes.   This step can be accomplished entirely within the cluster management client using the  RESTART  command, as shown here: After issuing each  X  RESTART  command, wait until the management client reports Node  X : Started (version ...) before  proceeding any further. You can verify that all existing data nodes were restarted using the updated configuration by checking the ndbinfo.nodes  table in the  mysql  client. Step 4: Perform a rolling restart of all cluster API nodes.   Shut down and restart each MySQL server acting as an SQL node in the cluster using  mysqladmin shutdown  followed by  mysqld_safe  (or Important 4485