To familiarize you with the basics, we describe the simplest possible configuration for a functional NDB Cluster. After this, you should be able to design your desired setup from the information provided in the other relevant sections of this chapter.
First, you need to create a configuration directory such as
/var/lib/mysql-cluster
, by executing the
following command as the system root
user:
$> mkdir /var/lib/mysql-cluster
In this directory, create a file named
config.ini
that contains the following
information. Substitute appropriate values for
HostName
and DataDir
as
necessary for your system.
# file "config.ini" - showing minimal setup consisting of 1 data node,
# 1 management server, and 3 MySQL servers.
# The empty default sections are not required, and are shown only for
# the sake of completeness.
# Data nodes must provide a hostname but MySQL Servers are not required
# to do so.
# If you do not know the hostname for your machine, use localhost.
# The DataDir parameter also has a default value, but it is recommended to
# set it explicitly.
# [api] and [mgm] are aliases for [mysqld] and [ndb_mgmd], respectively.
[ndbd default]
NoOfReplicas= 1
[mysqld default]
[ndb_mgmd default]
[tcp default]
[ndb_mgmd]
HostName= myhost.example.com
[ndbd]
HostName= myhost.example.com
DataDir= /var/lib/mysql-cluster
[mysqld]
[mysqld]
[mysqld]
You can now start the ndb_mgmd management
server. By default, it attempts to read the
config.ini
file in its current working
directory, so change location into the directory where the file is
located and then invoke ndb_mgmd:
$> cd /var/lib/mysql-cluster
$> ndb_mgmd
Then start a single data node by running ndbd:
$> ndbd
By default, ndbd looks for the management
server at localhost
on port 1186.
If you have installed MySQL from a binary tarball, you must to
specify the path of the ndb_mgmd and
ndbd servers explicitly. (Normally, these can
be found in /usr/local/mysql/bin
.)
Finally, change location to the MySQL data directory (usually
/var/lib/mysql
or
/usr/local/mysql/data
), and make sure that
the my.cnf
file contains the option necessary
to enable the NDB storage engine:
[mysqld]
ndbcluster
You can now start the MySQL server as usual:
$> mysqld_safe --user=mysql &
Wait a moment to make sure the MySQL server is running properly.
If you see the notice mysql ended
, check the
server's .err
file to find out what went
wrong.
If all has gone well so far, you now can start using the cluster.
Connect to the server and verify that the
NDBCLUSTER
storage engine is enabled:
$> mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1 to server version: 8.0.40
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> SHOW ENGINES\G
...
*************************** 12. row ***************************
Engine: NDBCLUSTER
Support: YES
Comment: Clustered, fault-tolerant, memory-based tables
*************************** 13. row ***************************
Engine: NDB
Support: YES
Comment: Alias for NDBCLUSTER
...
The row numbers shown in the preceding example output may be different from those shown on your system, depending upon how your server is configured.
Try to create an NDBCLUSTER
table:
$> mysql
mysql> USE test;
Database changed
mysql> CREATE TABLE ctest (i INT) ENGINE=NDBCLUSTER;
Query OK, 0 rows affected (0.09 sec)
mysql> SHOW CREATE TABLE ctest \G
*************************** 1. row ***************************
Table: ctest
Create Table: CREATE TABLE `ctest` (
`i` int(11) default NULL
) ENGINE=ndbcluster DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
1 row in set (0.00 sec)
To check that your nodes were set up properly, start the management client:
$> ndb_mgm
Use the SHOW command from within the management client to obtain a report on the cluster's status:
ndb_mgm> SHOW
Cluster Configuration
---------------------
[ndbd(NDB)] 1 node(s)
id=2 @127.0.0.1 (Version: 8.0.41-ndb-8.0.41, Nodegroup: 0, *)
[ndb_mgmd(MGM)] 1 node(s)
id=1 @127.0.0.1 (Version: 8.0.41-ndb-8.0.41)
[mysqld(API)] 3 node(s)
id=3 @127.0.0.1 (Version: 8.0.41-ndb-8.0.41)
id=4 (not connected, accepting connect from any host)
id=5 (not connected, accepting connect from any host)
At this point, you have successfully set up a working NDB Cluster
. You can now store data in the cluster by using any table created
with ENGINE=NDBCLUSTER
or its alias
ENGINE=NDB
.