The limitations discussed in this section occur by intention or design in MySQL Cluster Manager 8.0.40. Some of these items may become obsolete in future versions; we will update this section accordingly if and as those changes come about.
change process
command.
Currently, the change process
command can be used only to exchange an ndbd
process for an ndbmtd process, or the
reverse. That is, in effect, it can be used only to switch a
data node between a single-threaded process and a multithreaded
process. It cannot be used for changing a cluster node's
type (for example, you cannot change a data node to an SQL node,
management node, or NDB API application node).
Concurrent client sessions.
Currently there is no negotiation or arbitration between
multiple mcm clients. While it is possible to
use the client from multiple locations, you should be careful
always to allow a reconfiguration command issued in one
mcm client session to finish executing before
issuing a new command in a different client session. The same
must be ensured when using the -B
or
--background
option to
regain control before completion; see
Backgrounded commands and error handling.
IPv6 and host names (Windows).
When IPv6 support is enabled on Windows systems, host names
other than localhost
are resolved using IPv6.
When an IPv6-enabled Windows system is used as a MySQL NDB Cluster host
under MySQL Cluster Manager, you must reference it using its IPv4 address.
Otherwise, mcm will be unable to connect to
the agent process on that host.
This applies to host names used with the MySQL Cluster Manager client commands
create cluster
,
create site
,
add hosts
,
add package
,
delete package
,
stop agents
, and
add process
.
Use of antivirus software on Windows platforms. On-access scanning by antivirus software on Windows platforms might cause access to the cluster configuration file being denied for the mcmd agent, causing updates for the cluster configuration to fail sometimes.