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17.4.2 ndb_mgmd — The MySQL 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.

The following table includes options that are specific to the MySQL Cluster management server program ndb_mgmd. Additional descriptions follow the table. For options common to most MySQL Cluster programs (including ndb_mgmd), see Section 17.4.20, “Options Common to MySQL Cluster Programs — Options Common to MySQL Cluster Programs”.

Table 17.27  This table describes command-line options for the ndb_mgmd program

Format Description Added or Removed




Specify the cluster configuration file; in NDB-6.4.0 and later, needs --reload or --initial to override configuration cache if present

All MySQL 5.0 based releases



Print full configuration and exit

ADDED: 5.0.10



Run ndb_mgmd in daemon mode (default)

All MySQL 5.0 based releases


Do not run ndb_mgmd as a daemon

All MySQL 5.0 based releases


Run ndb_mgmd in interactive mode (not officially supported in production; for testing purposes only)

All MySQL 5.0 based releases


Do not provide any node id checks

All MySQL 5.0 based releases


Read cluster configuration data from the my.cnf file

All MySQL 5.0 based releases

It is not strictly necessary to specify a connection string when starting the management server. However, if you are using more than one management server, a connection string should be provided and each node in the cluster should specify its node ID explicitly.

See Section, “MySQL Cluster Connection Strings”, for information about using connection strings. Section 17.4.2, “ndb_mgmd — The MySQL Cluster Management Server Daemon”, describes other options for ndb_mgmd.

The following files are created or used by ndb_mgmd in its starting directory, and are placed in the DataDir as specified in the config.ini configuration file. In the list that follows, node_id is the unique node identifier.