This section provides information about NDB Cluster software and table file compatibility between different NDB Cluster 7.2 releases with regard to performing upgrades and downgrades as well as compatibility matrices and notes. You should already be familiar with installing and configuring NDB Cluster prior to attempting an upgrade or downgrade. See Chapter 5, Configuration of NDB Cluster.
Schema operations, including SQL DDL statements, cannot be performed while any data nodes are restarting, and thus during an online upgrade or downgrade of the cluster. For other information regarding the rolling restart procedure used to perform an online upgrade, see Section 7.5, “Performing a Rolling Restart of an NDB 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 NDB Cluster software. This is
especially true when planning a migration from NDB Cluster 7.1
(or earlier) to NDB Cluster 7.2, since the version of the
underlying MySQL Server also changes from MySQL 5.1 to MySQL
5.5. See Upgrading MySQL.
The table shown here provides information on NDB Cluster upgrade and downgrade compatibility among different releases of NDB Cluster 7.2. Additional notes about upgrades and downgrades to, from, or within the NDB Cluster 7.2 release series can be found immediately following the table.
Versions supported. The following versions of NDB Cluster are supported for upgrades to NDB Cluster 7.2 (7.2.4 and later):
NDB Cluster 7.1 GA releases (7.1.3 and later)
NDB Cluster 7.0 GA releases (7.0.5 and later)
NDB Cluster 6.3 GA releases (6.3.8 and later) that can be upgraded to NDB Cluster 7.1
For information about upgrades to and downgrades from NDB Cluster 7.3, see Upgrading and Downgrading NDB Cluster. For information about upgrades and downgrades in previous NDB Cluster release series, see the MySQL 5.1 Reference Manual.
In NDB Cluster 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 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 an NDB Cluster from NDB 7.2.6 and earlier to 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 NDB 7.2.6 or earlier. This issue was resolved in 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 NDB 7.2.13 or earlier from NDB 7.2.14 or later. Online upgrades from NDB 7.2.13 to later NDB Cluster 7.2 releases are supported.