This tool extracts configuration information for data nodes, SQL nodes, and API nodes from a cluster management node (and possibly its config.ini file).

Usage:

ndb_config options

The options available for this utility differ somewhat from those used with the other utilities, and so are listed in their entirety in the next section, followed by some examples.

Options:

Examples:

This utility is found in the libexec directory. It is part of an internal automated test framework used in testing and bedugging MySQL Cluster. Because it can control processes on remote systems, it is not advisable to use ndb_cpcd in a production cluster.

Because some users may be interested in employing the Cluster testing framework for their own development or testing purposes, we intend to make details of this application's usage available in the near future as part of the MySQL Internals Manual.

The source files for ndb_cpcd may be found in the directory storage/ndb/src/cw/cpcd, in the MySQL 5.0 source tree.

ndb_delete_all deletes all rows from the given NDB table. In some cases, this can be much faster than DELETE or even TRUNCATE.

Usage:

ndb_delete_all -c connect_string tbl_name -d db_name

This deletes all rows from the table named tbl_name in the database named db_name. It is exactly equivalent to executing TRUNCATE db_name.tbl_name in MySQL.

Additional Options:

ndb_desc provides a detailed description of one or more NDB tables.

Usage:

ndb_desc -c connect_string tbl_name -d db_name

Sample Output:

MySQL table creation and population statements:

USE test;

CREATE TABLE fish (
    id INT(11) NOT NULL AUTO_INCREMENT,
    name VARCHAR(20),

    PRIMARY KEY pk (id),
    UNIQUE KEY uk (name)
) ENGINE=NDBCLUSTER;

INSERT INTO fish VALUES 
    ('','guppy'), ('','tuna'), ('','shark'), 
    ('','manta ray'), ('','grouper'), ('','puffer');

Output from ndb_desc:

shell> ./ndb_desc -c localhost fish -d test -p
-- fish --
Version: 16777221
Fragment type: 5
K Value: 6
Min load factor: 78
Max load factor: 80
Temporary table: no
Number of attributes: 2
Number of primary keys: 1
Length of frm data: 268
Row Checksum: 1
Row GCI: 1
TableStatus: Retrieved
-- Attributes --
id Int PRIMARY KEY DISTRIBUTION KEY AT=FIXED ST=MEMORY
name Varchar(20;latin1_swedish_ci) NULL AT=SHORT_VAR ST=MEMORY

-- Indexes --
PRIMARY KEY(id) - UniqueHashIndex
uk(name) - OrderedIndex
PRIMARY(id) - OrderedIndex
uk$unique(name) - UniqueHashIndex

-- Per partition info --
Partition  Row count  Commit count  Frag fixed memory  Frag varsized memory
2          2          2             65536              327680
1          2          2             65536              327680
3          2          2             65536              327680

NDBT_ProgramExit: 0 - OK

Additional Options:

ndb_drop_index drops the specified index from an NDB table. It is recommended that you use this utility only as an example for writing NDB API applications — see the Warning later in this section for details.

Usage:

ndb_drop_index -c connect_string table_name index -d db_name

The statement shown above drops the index named index from the table in the database.

Additional Options: None that are specific to this application.

Warning: Operations performed on Cluster table indexes using the NDB API are not visible to MySQL and make the table unusable by a MySQL server. If you use this program to drop an index, then try to access the table from an SQL node, an error results, as shown here:

shell> ./ndb_drop_index -c localhost dogs ix -d ctest1
Dropping index dogs/idx...OK

NDBT_ProgramExit: 0 - OK

shell> ./mysql -u jon -p ctest1
Enter password: *******
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7 to server version: 5.1.12-beta-20060817

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW TABLES;
+------------------+
| Tables_in_ctest1 |
+------------------+
| a                |
| bt1              |
| bt2              |
| dogs             |
| employees        |
| fish             |
+------------------+
6 rows in set (0.00 sec)

mysql> SELECT * FROM dogs;
ERROR 1296 (HY000): Got error 4243 'Index not found' from NDBCLUSTER

In such a case, your only option for making the table available to MySQL again is to drop the table and re-create it. You can use either the SQL statementDROP TABLE or the ndb_drop_table utility (see Section 15.8.6, “ndb_drop_table — Drop NDB Table”) to drop the table.

ndb_drop_table drops the specified NDB table. (If you try to use this on a table created with a storage engine other than NDB, it fails with the error 723: No such table exists.) This operation is extremely fast — in some cases, it can be an order of magnitude faster than using DROP TABLE on an NDB table from MySQL.

Usage:

ndb_drop_table -c connect_string tbl_name -d db_name

Additional Options: None.

ndb_error_reporter creates an archive from data node and management node log files that can be used to help diagnose bugs or other problems with a cluster. It is highly recommended that you make use of this utility when filing reports of bugs in MySQL Cluster.

Usage:

ndb_error_reporter path/to/config-file [username] [--fs]

This utility is intended for use on a management node host, and requires the path to the management host configuration file (config.ini). Optionally, you can supply the name of a user that is able to access the cluster's data nodes via SSH, in order to copy the data node log files. ndb_error_reporter then includes all of these files in archive that is created in the same directory in which it is run. The archive is named ndb_error_report_YYYYMMDDHHMMSS.tar.bz2, where YYYYMMDDHHMMSS is a datetime string.

If the --fs is used, then the data node filesystems are also copied to the management host and included in the archive that is produced by this script. As data node filesystems can be extremely large even after being compressed, we ask that you please do not send archives created using this option to MySQL AB unless you are specifically requested to do so.

ndb_print_backup_file obtains diagnostic information from a cluster backup file.

Usage:

ndb_print_backup_file file_name

file_name is the name of a cluster backup file. This can be any of the files (.Data, .ctl, or .log file) found in a cluster backup directory. These files are found in the data node's backup directory under the subdirectory BACKUP-#, where # is the sequence number for the backup. For more information about cluster backup files and their contents, see Section 15.7.1, “Cluster Backup Concepts”.

Like ndb_print_schema_file and ndb_print_sys_file (and unlike most of the other NDB utilities that are intended to be run on a management server host or to connect to a management server) ndb_print_backup_file must be run on a cluster data node, since it accesses the data node filesystem directly. Because it does not make use of the management server, this utility can be used when the management server is not running, and even when the cluster has been completely shut down.

Additional Options: None.

ndb_print_schema_file obtains diagnostic information from a cluster schema file.

Usage:

ndb_print_schema_file file_name

file_name is the name of a cluster schema file.

Like ndb_print_backup_file and ndb_print_sys_file (and unlike most of the other NDB utilities that are intended to be run on a management server host or to connect to a management server) ndb_schema_backup_file must be run on a cluster data node, since it accesses the data node filesystem directly. Because it does not make use of the management server, this utility can be used when the management server is not running, and even when the cluster has been completely shut down.

Additional Options: None.

ndb_print_sys_file obtains diagnostic information from a cluster system file.

Usage:

ndb_print_sys_file file_name

file_name is the name of a cluster system file (sysfile). Cluster system files are located in a data node's data directory (DataDir); the path under this directory to system files matches the pattern ndb_#_fs/D#/DBDIH/P#.sysfile. In each case, the # represents a number (not necessarily the same number).

Like ndb_print_backup_file and ndb_print_schema_file (and unlike most of the other NDB utilities that are intended to be run on a management server host or to connect to a management server) ndb_print_backup_file must be run on a cluster data node, since it accesses the data node filesystem directly. Because it does not make use of the management server, this utility can be used when the management server is not running, and even when the cluster has been completely shut down.

Additional Options: None.

ndb_select_all prints all rows from an NDB table to stdout.

Usage:

ndb_select_all -c connect_string tbl_name -d db_name [> file_name]

Additional Options:

Sample Output:

Output from a MySQL SELECT statement:

mysql> SELECT * FROM ctest1.fish;
+----+-----------+
| id | name      |
+----+-----------+
|  3 | shark     |
|  6 | puffer    |
|  2 | tuna      |
|  4 | manta ray |
|  5 | grouper   |
|  1 | guppy     |
+----+-----------+
6 rows in set (0.04 sec)

Output from the equivalent invocation of ndb_select_all:

shell> ./ndb_select_all -c localhost fish -d ctest1
id      name
3       [shark]
6       [puffer]
2       [tuna]
4       [manta ray]
5       [grouper]
1       [guppy]
6 rows returned

NDBT_ProgramExit: 0 - OK

Note that all string values are enclosed by square brackets (“[...]”) in the output of ndb_select_all. For a further example, consider the table created and populated as shown here:

CREATE TABLE dogs (
    id INT(11) NOT NULL AUTO_INCREMENT,
    name VARCHAR(25) NOT NULL,
    breed VARCHAR(50) NOT NULL,
    PRIMARY KEY pk (id),
    KEY ix (name)
) 
ENGINE=NDB;

INSERT INTO dogs VALUES 
    ('', 'Lassie', 'collie'),
    ('', 'Scooby-Doo', 'Great Dane'),
    ('', 'Rin-Tin-Tin', 'German Shepherd'),
    ('', 'Rosscoe', 'Mutt');

This demonstrates the use of several additional ndb_select_all options:

shell> ./ndb_select_all -d ctest1 dogs -o ix -z --gci        
GCI     id name           breed
834461  2  [Scooby-Doo]   [Great Dane]
834878  4  [Rosscoe]      [Mutt]
834463  3  [Rin-Tin-Tin]  [German Shepherd]
835657  1  [Lassie]       [Collie]
4 rows returned

NDBT_ProgramExit: 0 - OK

ndb_select_count prints the number of rows in one or more NDB tables. With a single table, the result is equivalent to that obtained by using the MySQL statement SELECT COUNT(*) FROM tbl_name.

Usage:

ndb_select_count [-c connect_string] -ddb_name tbl_name[, tbl_name2[, ...]]

Additional Options: None that are specific to this application. However, you can obtain row counts from multiple tables in the same database by listing the table names separated by spaces when invoking this command, as shown under Sample Output.

Sample Output:

shell> ./ndb_select_count -c localhost -d ctest1 fish dogs
6 records in table fish
4 records in table dogs

NDBT_ProgramExit: 0 - OK

ndb_show_tables displays a list of all NDB database objects in the cluster. By default, this includes not only both user-created tables and NDB system tables, but NDB-specific indexes, and internal triggers, as well.

Usage:

ndb_show_tables [-c connect_string]

Additional Options:

Note: Only user-created Cluster tables may be accessed from MySQL; system tables such as SYSTAB_0 are not visible to mysqld. However, you can examine the contents of system tables using NDB API applications such as ndb_select_all (see Section 15.8.11, “ndb_select_all — Print Rows from NDB Table”).

This is a Perl script that can be used to estimate the amount of space that would be required by a MySQL database if it were converted to use the NDBCluster storage engine. Unlike the other utilities discussed in this section, it does not require access to a MySQL Cluster (in fact, there is no reason for it to do so). However, it does need to access the MySQL server on which the database to be tested resides.

Requirements:

ndb_size.pl and ndb_size.tmpl can also be found in the MySQL sources in storage/ndb/tools. If these files are not present in your MySQL installation, you can obtain them from the MySQLForge project page.

Usage:

perl ndb_size.pl db_name hostname username password > file_name.html

The command shown connects to the MySQL server at hostname using the account of the user username having the password password, analyses all of the tables in database db_name, and generates a report in HTML format which is directed to the file file_name.html. (Without the redirection, the output is sent to stdout.) This figure shows partial sample output as viewed in a Web browser:

The output from this script includes:

ndb_waiter repeatedly (each 100 milliseconds) prints out the status of all cluster data nodes until either the cluster reaches a given status or the --timeout limit is exceeded, then exits. By default, it waits for the cluster to achieve STARTED status, in which all nodes have started and connected to the cluster. This can be overridden using the --no-contact and --not-started options (see Additional Options).

The node states reported by this utility are as follows:

Usage:

ndb_waiter [-c connect_string]

Additional Options:

Sample Output:

Shown here is the output from ndb_waiter when run against a 4-node cluster in which two nodes have been shut down and then started again manually. Duplicate reports (indicated by “...”) are omitted.

shell> ./ndb_waiter -c localhost

Connecting to mgmsrv at (localhost)
State node 1 STARTED
State node 2 NO_CONTACT
State node 3 STARTED
State node 4 NO_CONTACT
Waiting for cluster enter state STARTED

...

State node 1 STARTED
State node 2 UNKNOWN
State node 3 STARTED
State node 4 NO_CONTACT
Waiting for cluster enter state STARTED

...

State node 1 STARTED
State node 2 STARTING
State node 3 STARTED
State node 4 NO_CONTACT
Waiting for cluster enter state STARTED

...

State node 1 STARTED
State node 2 STARTING
State node 3 STARTED
State node 4 UNKNOWN
Waiting for cluster enter state STARTED

...

State node 1 STARTED
State node 2 STARTING
State node 3 STARTED
State node 4 STARTING
Waiting for cluster enter state STARTED

...

State node 1 STARTED
State node 2 STARTED
State node 3 STARTED
State node 4 STARTING
Waiting for cluster enter state STARTED

...

State node 1 STARTED
State node 2 STARTED
State node 3 STARTED
State node 4 STARTED
Waiting for cluster enter state STARTED

NDBT_ProgramExit: 0 - OK

Note: If no connectstring is specified, then ndb_waiter tries to connect to a management on localhost, and reports Connecting to mgmsrv at (null).