MySQL 8.0 Release Notes
MySQL 8.0 Source Code Documentation
Thendb_mgmmanagement 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 byndb_mgm.
To start the management client, it is necessary to supply the host name and port number of the management server:
shell> ndb_mgm [host_name[port_num]]For example:
shell> ndb_mgm ndb_mgmd.mysql.com 1186The default host name and port number arelocalhostand 1186, respectively.
All options that can be used withndb_mgmare shown in the following table. Additional descriptions follow the table.
Table 23.27 Command-line options used with the program ndb_mgm
| Format | Description | Added, Deprecated, or Removed |
|---|---|---|
| Get decryption password in a secure fashion from STDIN; use together with --execute and START BACKUP command | ADDED: NDB 8.0.24 |
|
| Directory containing character sets | (Supported in all NDB releases based on MySQL 8.0) |
|
| Set number of times to retry connection before giving up; 0 means 1 attempt only (and no retries) | (Supported in all NDB releases based on MySQL 8.0) |
|
| Number of seconds to wait between attempts to contact management server | (Supported in all NDB releases based on MySQL 8.0) |
|
| Same as --ndb-connectstring | (Supported in all NDB releases based on MySQL 8.0) |
|
| Write core file on error; used in debugging | (Supported in all NDB releases based on MySQL 8.0) |
|
| Read given file after global files are read | (Supported in all NDB releases based on MySQL 8.0) |
|
| Read default options from given file only | (Supported in all NDB releases based on MySQL 8.0) |
|
| Also read groups with concat(group, suffix) | (Supported in all NDB releases based on MySQL 8.0) |
|
| Cause START BACKUP to encrypt whenever making a backup, prompting for password if not supplied by user | ADDED: NDB 8.0.24 |
|
| Execute command and exit | (Supported in all NDB releases based on MySQL 8.0) |
|
| Display help text and exit | (Supported in all NDB releases based on MySQL 8.0) |
|
| Read given path from login file | (Supported in all NDB releases based on MySQL 8.0) |
|
| Set connect string for connecting to ndb_mgmd. Syntax: "[nodeid=id;][host=]hostname[:port]". Overrides entries in NDB_CONNECTSTRING and my.cnf | (Supported in all NDB releases based on MySQL 8.0) |
|
| Same as --ndb-connectstring | (Supported in all NDB releases based on MySQL 8.0) |
|
| Set node ID for this node, overriding any ID set by --ndb-connectstring | (Supported in all NDB releases based on MySQL 8.0) |
|
| Enable optimizations for selection of nodes for transactions. Enabled by default; use --skip-ndb-optimized-node-selection to disable | (Supported in all NDB releases based on MySQL 8.0) |
|
| Do not read default options from any option file other than login file | (Supported in all NDB releases based on MySQL 8.0) |
|
| Print program argument list and exit | (Supported in all NDB releases based on MySQL 8.0) |
|
| Set number of times to retry connection before giving up; synonym for --connect-retries | (Supported in all NDB releases based on MySQL 8.0) |
|
| Display help text and exit; same as --help | (Supported in all NDB releases based on MySQL 8.0) |
|
| Display version information and exit | (Supported in all NDB releases based on MySQL 8.0) |
--backup-password-from-stdin[=TRUE|FALSE]Command-Line Format --backup-password-from-stdin[=value]Introduced 8.0.24-ndb-8.0.24 Type Boolean Default Value FALSEThis 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--executeas well.-
Command-Line Format --character-sets-dir=pathDirectory containing character sets.
-
Command-Line Format --connect-retries=#Type Numeric Default Value 3Minimum Value 0Maximum Value 4294967295This 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.此选项的同义词
--try-reconnectoption, which is now deprecated. -
Command-Line Format --connect-retry-delay=#Type Integer Default Value 5Minimum Value 0Maximum Value 5Number of seconds to wait between attempts to contact management server.
-
Command-Line Format --connect-string=connection-stringType String Default Value [none]Same as --ndb-connectstring.
-
Command-Line Format --core-fileWrite core file on error; used in debugging.
-
Command-Line Format --defaults-extra-file=pathType String Default Value [none]Read given file after global files are read.
-
Command-Line Format --defaults-file=pathType String Default Value [none]Read default options from given file only.
-
Command-Line Format --defaults-group-suffix=stringType String Default Value [none]Also read groups with concat(group, suffix).
-
Command-Line Format --encrypt-backup[=TRUE|FALSE]Introduced 8.0.24-ndb-8.0.24 Type Boolean Default Value TRUEWhen used, this option causes all backups to be encrypted. To make this happen wheneverndb_mgmis run, put the option in the
[ndb_mgm]section of themy.cnffile. -
Command-Line Format --execute=nameThis 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
SHOWin the management client:shell> ndb_mgm -e "SHOW" shell> ndb_mgm --execute="SHOW"This is analogous to how the
--executeor-eoption works with themysqlcommand-line client. SeeSection 4.2.2.1, “Using Options on the Command Line”.NoteIf the management client command to be passed using this option contains any space characters, then the commandmustbe 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.
-
Command-Line Format --helpDisplay help text and exit.
-
Command-Line Format --login-path=pathType String Default Value [none]Read given path from login file.
-
Command-Line Format --ndb-connectstring=connection-stringType 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.
-
Command-Line Format --ndb-nodeid=#Type Integer Default Value [none]Set node ID for this node, overriding any ID set by --ndb-connectstring.
-
Command-Line Format --ndb-mgmd-host=connection-stringType String Default Value [none]Same as --ndb-connectstring.
--ndb-optimized-node-selectionCommand-Line Format --ndb-optimized-node-selectionEnable optimizations for selection of nodes for transactions. Enabled by default; use
--skip-ndb-optimized-node-selectionto disable.-
Command-Line Format --no-defaultsDo not read default options from any option file other than login file.
-
Command-Line Format --print-defaultsPrint program argument list and exit.
-
Command-Line Format --try-reconnect=#Deprecated Yes Type Numeric Type Integer Default Value 12Default Value 3Minimum Value 0Maximum Value 4294967295If 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
numberbefore giving up and reporting an error instead.This option is deprecated and subject to removal in a future release. Use
--connect-retries, instead. -
Command-Line Format --usageDisplay help text and exit; same as --help.
-
Command-Line Format --versionDisplay version information and exit.
Additional information about usingndb_mgmcan be found inSection 23.6.1, “Commands in the NDB Cluster Management Client”.