The table shown here provides information on MySQL Cluster upgrade and downgrade compatibility among different releases of MySQL Cluster NDB 6.1, 6.2, and 6.3. Additional notes about upgrades and downgrades to, from, or within the MySQL Cluster NDB 6.x release series can be found immediately following the table.

Availability of older releases. MySQL Cluster NDB 6.1 is no longer in production; information about this series of releases is of historical interest only. MySQL Cluster NDB 6.2 is still available, but is no longer supported in new deployments. If you are still using a MySQL Cluster NDB 6.1 or MySQL Cluster NDB 6.2 release, you should upgrade to the most recent MySQL Cluster NDB 7.0 or MySQL Cluster NDB 7.1 release as soon as possible.
It is not possible to upgrade from MySQL Cluster NDB 6.1.2 (or an older 6.1 release) directly to 6.1.4 or a newer NDB 6.1 release, or to downgrade from 6.1.4 (or a newer 6.1 release) directly to 6.1.2 or an older NDB 6.1 release; in either case, you must upgrade or downgrade to MySQL Cluster NDB 6.1.3 first.
It is not possible to perform an online downgrade from MySQL Cluster NDB 6.1.8 (or a newer 6.1 release) to MySQL Cluster NDB 6.1.7 (or an older 6.1 release).
MySQL Cluster NDB 6.1.6 and 6.1.18 were not released.
It is not possible to perform an online upgrade or downgrade between MySQL Cluster NDB 6.2 and any previous release series (including mainline MySQL 5.1 and MySQL Cluster NDB 6.1); it is necessary to perform a dump and reload. However, it should be possible to perform online upgrades or downgrades between any MySQL Cluster NDB 6.2 release and any MySQL Cluster NDB 6.3 release up to and including 6.3.7.
Internal column specification changes.
The internal specifications for columns in
NDB tables changed in MySQL
Cluster NDB 6.1.17 and 6.2.1 to enable compatibility with
later MySQL Cluster releases implementing online adding and
dropping of columns (MySQL 5.1.17 through MySQL 5.1.23; MySQL
Cluster NDB 6.2.3 and later; MySQL Cluster NDB 6.3.2 and
later). This change is not backward-compatible with earlier
MySQL Server or MySQL Cluster releases.
To make tables created in earlier versions compatible with online adding and dropping of columns in later versions, it is necessary to force MySQL Cluster to convert the tables to the new format by following this procedure following an upgrade:
Upgrade the MySQL Cluster software on all data, management, and SQL nodes
Back up all NDB tables
Shut down the cluster (all data, management, and SQL nodes)
Restart the cluster, starting all data nodes with the
--initial option (to clear and
rebuild the data node file systems)
Restore the tables from backup
To minimize possible later difficulties, it is strongly advised
that the procedure outlined above be followed as soon as
possible after to upgrading between the versions indicated. The
procedure is not necessary for
NDBCLUSTER tables created in any of
the following versions:
MySQL Cluster NDB 6.1.8 or a later MySQL Cluster NDB 6.1 release
MySQL Cluster 6.2.1 or a later MySQL Cluster NDB 6.2 release
Any MySQL Cluster NDB 6.3 release (or later MySQL Cluster release series)
Tables created in the versions listed previously (or later versions, as indicated) are already compatible with adding and dropping of columns online (as implemented beginning with MySQL Cluster NDB 6.2.5 and MySQL Cluster NDB 6.3.2).
Additional issues encountered when upgrading or downgrading to or from MySQL Cluster NDB 6.2 and MySQL Cluster NDB 6.3 releases are listed here:
It was not possible to perform an online upgrade between any MySQL Cluster NDB 6.2 release and MySQL Cluster NDB 6.3.8 and later MySQL Cluster 6.3 releases. This issue was fixed in MySQL Cluster NDB 6.3.21. (Bug #41435)
Online downgrades between MySQL Cluster NDB 6.2.5 and earlier releases are not supported.
Online downgrades between MySQL Cluster NDB 6.3.8 and earlier releases are not supported.