NDB_MGM(1)

NAME
ndb_mgm - the NDB Cluster management client

SYNOPSIS

ndb_mgm options

DESCRIPTION

The ndb_mgm management client process is actually not needed to run the cluster. Its value lies in providing a set of commands for checking the cluster's status, starting backups, and performing other administrative functions. The management client accesses the management server using a C API. Advanced users can also employ this API for programming dedicated management processes to perform tasks similar to those performed by ndb_mgm.

To start the management client, it is necessary to supply the host name and port number of the management server:

    $> ndb_mgm [host_name [port_num]]

For example:

    $> ndb_mgm ndb_mgmd.mysql.com 1186

The default host name and port number are localhost and 1186, respectively.

All options that can be used with ndb_mgm are shown in the following table. Additional descriptions follow the table.

    • --backup-password-from-stdin[=TRUE|FALSE]
    Command-Line Format | --backup-password-from-stdin

    This option enables input of the backup password from the system shell (stdin) when using --execute "START BACKUP" or similar to create a backup. Use of this option requires use of --execute as well.

    • --character-sets-dir
    Command-Line Format | --character-sets-dir=path

    Directory containing character sets.

    • --connect-retries=#
    Command-Line Format | --connect-retries=#
    Type | Numeric
    Default Value | 3
    Minimum Value | 0
    Maximum Value | 4294967295

    This option specifies the number of times following the first attempt to retry a connection before giving up (the client always tries the connection at least once). The length of time to wait per attempt is set using --connect-retry-delay.

    This option is synonymous with the --try-reconnect option, which is now deprecated.

    • --connect-retry-delay
    Command-Line Format | --connect-retry-delay=#
    Type | Integer
    Default Value | 5
    Minimum Value | 0
    Maximum Value | 5

    Number of seconds to wait between attempts to contact management server.

    • --connect-string
    Command-Line Format | --connect-string=connection_string
    Type | String
    Default Value | [none]

    Same as --ndb-connectstring.

    • --core-file
    Command-Line Format | --core-file

    Write core file on error; used in debugging.

    • --defaults-extra-file
    Command-Line Format | --defaults-extra-file=path
    Type | String
    Default Value | [none]

    Read given file after global files are read.

    • --defaults-file
    Command-Line Format | --defaults-file=path
    Type | String
    Default Value | [none]

    Read default options from given file only.

    • --defaults-group-suffix
    Command-Line Format | --defaults-group-suffix=string
    Type | String
    Default Value | [none]

    Also read groups with concat(group, suffix).

    • --encrypt-backup
    Command-Line Format | --encrypt-backup

    When used, this option causes all backups to be encrypted. To make this happen whenever ndb_mgm is run, put the option in the [ndb_mgm] section of the my.cnf file.

    • --execute=command, -e command
    Command-Line Format | --execute=command

    This option can be used to send a command to the NDB Cluster management client from the system shell. For example, either of the following is equivalent to executing SHOW in the management client:

        $> ndb_mgm -e "SHOW"
        $> ndb_mgm --execute="SHOW"

    This is analogous to how the --execute or -e option works with the mysql command-line client. See Section 6.2.2.1, “Using Options on the Command Line”.

        Note
        If the management client command to be passed using this option contains any space characters, then the command must be enclosed in quotation marks. Either single or double quotation marks may be used. If the management client command contains no space characters, the quotation marks are optional.

    • --help
    Command-Line Format | --help

    Display help text and exit.

    • --login-path
    Command-Line Format | --login-path=path
    Type | String
    Default Value | [none]

    Read given path from login file.

    • --no-login-paths
    Command-Line Format | --no-login-paths

    Skips reading options from the login path file.

    • --ndb-connectstring
    Command-Line Format | --ndb-connectstring=connection_string
    Type | String
    Default Value | [none]

    Set connect string for connecting to ndb_mgmd. Syntax: [nodeid=id;][host=]hostname[:port]. Overrides entries in NDB_CONNECTSTRING and my.cnf.

    • --ndb-nodeid
    Command-Line Format | --ndb-nodeid=#
    Type | Integer
    Default Value | [none]

    Set node ID for this node, overriding any ID set by --ndb-connectstring.

    • --ndb-mgm-tls
    Command-Line Format | --ndb-mgm-tls=level
    Type | Enumeration
    Default Value | relaxed
    Valid Values | relaxed strict

    Sets the level of TLS support required to connect to the management server; one of relaxed or strict. relaxed (the default) means that a TLS connection is attempted, but success is not required; strict means that TLS is required to connect.

    • --ndb-mgmd-host
    Command-Line Format | --ndb-mgmd-host=connection_string
    Type | String
    Default Value | [none]

    Same as --ndb-connectstring.

    • --ndb-optimized-node-selection
    Command-Line Format | --ndb-optimized-node-selection

    Enable optimizations for selection of nodes for transactions. Enabled by default; use --skip-ndb-optimized-node-selection to disable.

    • --ndb-tls-search-path
    Command-Line Format | --ndb-tls-search-path=list
    Type | Path name
    Default Value (Unix) | $HOME/ndb-tls
    Default Value (Windows) | $HOMEDIR/ndb-tls

    Specify a list of directories to search for a CA file. On Unix platforms, the directory names are separated by colons (:); on Windows systems, the semicolon character (;) is used as the separator. A directory reference may be relative or absolute; it may contain one or more environment variables, each denoted by a prefixed dollar sign ($), and expanded prior to use.

    Searching begins with the leftmost named directory and proceeds from left to right until a file is found. An empty string denotes an empty search path, which causes all searches to fail. A string consisting of a single dot (.) indicates that the search path limited to the current working directory.

    If no search path is supplied, the compiled-in default value is used. This value depends on the platform used: On Windows, this is \ndb-tls; on other platforms (including Linux), it is $HOME/ndb-tls. This can be overridden by compiling NDB Cluster using -DWITH_NDB_TLS_SEARCH_PATH.

    • --no-defaults
    Command-Line Format | --no-defaults

    Do not read default options from any option file other than login file.

    • --print-defaults
    Command-Line Format | --print-defaults

    Print program argument list and exit.

    • --test-tls
    Command-Line Format | --test-tls

    Connect using TLS, then exit. Output if successful is similar to what is shown here:

        >$ ndb_mgm --test-tls
        Connected to Management Server at: sakila:1186
        >$

    See Section 25.6.19.5, “TLS Link Encryption for NDB Cluster”, for more information.

    • --try-reconnect=number
    Command-Line Format | --try-reconnect=#
    Deprecated | Yes
    Type | Numeric
    Type | Integer
    Default Value | 12
    Default Value | 3
    Minimum Value | 0
    Maximum Value | 4294967295

    If the connection to the management server is broken, the node tries to reconnect to it every 5 seconds until it succeeds. By using this option, it is possible to limit the number of attempts to number before giving up and reporting an error instead.

    This option is deprecated and subject to removal in a future release. Use --connect-retries, instead.

    • --usage
    Command-Line Format | --usage

    Display help text and exit; same as --help.

    • --version
    Command-Line Format | --version

    Display version information and exit.

Additional information about using ndb_mgm can be found in Section 25.6.1, “Commands in the NDB Cluster Management Client”.

COPYRIGHT

Copyright © 1997, 2025, Oracle and/or its affiliates.

This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.

This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.

SEE ALSO
For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.

AUTHOR
Oracle Corporation (http://dev.mysql.com/).