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MySQL NDB Cluster 6.1-7.1

MySQL NDB Cluster 6.1-7.1  /  MySQL Cluster Programs  /  Options Common to MySQL Cluster Programs — Options Common to MySQL Cluster Programs

6.26 Options Common to MySQL Cluster Programs — Options Common to MySQL Cluster Programs

All MySQL Cluster programs accept the options described in this section, with the following exceptions:

Users of earlier MySQL Cluster versions should note that some of these options have been changed to make them consistent with one another as well as with mysqld. You can use the --help option with any MySQL Cluster program—with the exception of ndb_print_backup_file, ndb_print_schema_file, and ndb_print_sys_file—to view a list of the options which the program supports.

The options in the following table are common to all MySQL Cluster executables (except those noted previously in this section).

Table 6.20 This table describes command-line options common to all MySQL Cluster programs

Format Description Added or Removed




Display help message and exit

All MySQL 5.1 based releases


Directory where character sets are installed

All MySQL 5.1 based releases


Write core on errors (defaults to TRUE in debug builds)

All MySQL 5.1 based releases


Enable output from debug calls. Can be used only for versions compiled with debugging enabled

All MySQL 5.1 based releases




Set connection string for connecting to ndb_mgmd. Syntax: [nodeid=<id>;][host=]<hostname>[:<port>]. Overrides entries specified in NDB_CONNECTSTRING or my.cnf.

All MySQL 5.1 based releases


Set the host (and port, if desired) for connecting to management server

All MySQL 5.1 based releases


Set node id for this node

All MySQL 5.1 based releases


Select nodes for transactions in a more optimal way

All MySQL 5.1 based releases


Allow for optimization using shared memory connections where available (was EXPERIMENTAL, later REMOVED)

REMOVED: NDB 7.0.16, NDB 7.1.5



Output version information and exit

All MySQL 5.1 based releases

For options specific to individual MySQL Cluster programs, see Chapter 6, MySQL Cluster Programs.

See Section, “MySQL Server Options for MySQL Cluster”, for mysqld options relating to MySQL Cluster.

  • --help, --usage, -?

    Command-Line Format--help

    Prints a short list with descriptions of the available command options.

  • --character-sets-dir=name

    Command-Line Format--character-sets-dir=dir_name
    Permitted ValuesTypedirectory name

    Tells the program where to find character set information.

  • --ndb-connectstring=connection_string, --connect-string=connection_string, -c connection_string

    Command-Line Format--ndb-connectstring=connectstring
    Permitted ValuesTypestring

    This option takes a MySQL Cluster connection string that specifies the management server for the application to connect to, as shown here:

    shell> ndbd --ndb-connectstring="nodeid=2;"

    For more information, see Section 5.3.3, “MySQL Cluster Connection Strings”.

  • --core-file

    Command-Line Format--core-file
    Permitted ValuesTypeboolean

    Write a core file if the program dies. The name and location of the core file are system-dependent. (For MySQL Cluster programs nodes running on Linux, the default location is the program's working directory—for a data node, this is the node's DataDir.) For some systems, there may be restrictions or limitations; for example, it might be necessary to execute ulimit -c unlimited before starting the server. Consult your system documentation for detailed information.

    If MySQL Cluster was built using the --debug option for configure, then --core-file is enabled by default. For regular builds, --core-file is disabled by default.

  • --debug[=options]

    Command-Line Format--debug=options
    Permitted ValuesTypestring

    This option can be used only for versions compiled with debugging enabled. It is used to enable output from debug calls in the same manner as for the mysqld process.

  • --ndb-mgmd-host=host[:port]

    Command-Line Format--ndb-mgmd-host=host[:port]
    Permitted ValuesTypestring

    Can be used to set the host and port number of a single management server for the program to connect to. If the program requires node IDs or references to multiple management servers (or both) in its connection information, use the --ndb-connectstring option instead.

  • --ndb-nodeid=#

    Command-Line Format--ndb-nodeid=#
    Permitted ValuesTypenumeric

    Sets this node's MySQL Cluster node ID. The range of permitted values depends on the node's type (data, management, or API) and the MySQL Cluster software version. See Section 3.6.2, “Limits and Differences of MySQL Cluster from Standard MySQL Limits”, for more information.

  • --ndb-optimized-node-selection

    Command-Line Format--ndb-optimized-node-selection
    Permitted ValuesTypeboolean

    Optimize selection of nodes for transactions. Enabled by default.

  • --version, -V

    Command-Line Format--version

    Prints the MySQL Cluster version number of the executable. The version number is relevant because not all versions can be used together, and the MySQL Cluster startup process verifies that the versions of the binaries being used can co-exist in the same cluster. This is also important when performing an online (rolling) software upgrade or downgrade of MySQL Cluster.

    See Section 7.5, “Performing a Rolling Restart of a MySQL Cluster”), for more information.

  • --ndb-shm

    Command-Line Format--ndb-shm
    Permitted ValuesTypeboolean

    In older versions of MySQL Cluster, this experimental option allowed the application to use shared memory for optimization when available. --ndb-shm was removed from all MySQL Cluster programs beginning with MySQL Cluster NDB 7.0.16 and MySQL Cluster 7.1.5.