This section provides information about MySQL Cluster software and table file compatibility between different MySQL Cluster NDB 7.2 releases with regard to performing upgrades and downgrades as well as compatibility matrices and notes. You are expected already to be familiar with installing and configuring a MySQL Cluster prior to attempting an upgrade or downgrade. See Section 18.3, “Configuration of MySQL Cluster”.
For information regarding the rolling restart procedure used to perform an online upgrade, see Section 18.5.5, “Performing a Rolling Restart of a MySQL Cluster”.
Only compatibility between MySQL versions with regard to
NDBCLUSTER is taken into account in
this section, and there are likely other issues to be
considered. As with any other MySQL software upgrade
or downgrade, you are strongly encouraged to review the relevant
portions of the MySQL Manual for the MySQL versions from which
and to which you intend to migrate, before attempting an upgrade
or downgrade of the MySQL Cluster software. This is
especially true when planning a migration from MySQL Cluster NDB
7.1 (or earlier) to MySQL Cluster NDB 7.2, since the version of
the underlying MySQL Server also changes from MySQL 5.1 to MySQL
5.5. See Section 2.11.1, “Upgrading MySQL”.
The table shown here provides information on MySQL Cluster upgrade and downgrade compatibility among different releases of MySQL Cluster NDB 7.2. Additional notes about upgrades and downgrades to, from, or within the MySQL Cluster NDB 7.2 release series can be found immediately following the table.
Versions supported. The following versions of MySQL Cluster are supported for upgrades to MySQL Cluster NDB 7.2 (7.2.4 and later):
MySQL Cluster NDB 7.1 GA releases (7.1.3 and later)
MySQL Cluster NDB 7.0 GA releases (7.0.5 and later)
MySQL Cluster NDB 6.3 GA releases (6.3.8 and later) that can be upgraded to MySQL Cluster NDB 7.1
For information about upgrades to and downgrades from MySQl Cluster NDB 7.3, see Upgrading and Downgrading MySQL Cluster. For information about upgrades and downgrades in previous MySQL Cluster release series, see Upgrade and Downgrade Compatibility: MySQL Cluster NDB 6.x, and Upgrade and downgrade compatibility: MySQL Cluster NDB 7.x.
In MySQL Cluster NDB 7.2, the default values for a number of node configuration parameters have changed. See Improved default values for data node configuration parameters, for a listing of these.
Other known issues include the following:
In MySQL Cluster NDB 7.2.7 and later, the size of the hash map is 3840 LDM threads, an increase from 240 in previous versions. When upgrading a MySQL Cluster from MySQL Cluster NDB 7.2.6 and earlier to MySQL Cluster NDB 7.2.9 or later, you can modify existing tables online to take advantage of the new size: following the upgrade, increase the number of fragments by (for example) adding new data nodes to the cluster, and then execute
ALTER ONLINE TABLE ... REORGANIZE PARTITIONon any tables that were created in the older version. Following this, these tables can use the larger hash map size. (Bug #14645319)
Due to this change, it was not possible to downgrade online to MySQL Cluster NDB 7.2.6 or earlier. This issue was resolved in MySQL Cluster NDB 7.2.11, where the size is made configurable using the
DefaultHashMapSizeparameter. (Bug #14800539) See the description of this parameter for more information.
It is not possible to downgrade online to MySQL Cluster NDB 7.2.13 or earlier from MySQL Cluster NDB 7.2.14 or later. Online upgrades from MySQL Cluster NDB 7.2.13 to later MySQL Cluster NDB 7.2 releases are supported.