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 17.3, “MySQL Cluster Configuration”.
For information regarding the rolling restart procedure used to perform an online upgrade, see Section 17.5.5, “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 2.12.1, “Upgrading MySQL”.
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 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.
NDB API, ClusterJ, and other applications used with recent releases of MySQL Cluster NDB 6.3 and later should continue to work with MySQL Cluster NDB 7.2.4 and later without rewriting or recompiling.
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.
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
ONLINE TABLE ... REORGANIZE PARTITION on 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
parameter. (Bug #14800539) See the description of this parameter
for more information.