MySQL Cluster Manager 9.2.0 User Manual
The importing process consists generally of the steps listed here:
Prepare the “wild” cluster for migration.
Verify PID files for cluster processes.
Create and configure in MySQL Cluster Manager a “target” cluster whose configuration matches that of the “wild” cluster.
Perform a test run, and then execute the
import cluster
command.
This expanded listing breaks down each of the tasks just mentioned into smaller steps:
Prepare the “wild” cluster for migration
It is highly recommended that you take a complete backup of the “wild” cluster before you make changes to it, using the ndb_mgm client. For more information, see Using The NDB Cluster Management Client to Create a Backup.
Any cluster processes that are under the control of the
system's boot-time process management facility,
such as /etc/init.d
on Linux
systems or the Services Manager on Windows platforms,
should be removed from its control.
The wild cluster's configuration must meet the following requirements, and it should be reconfigured and restarted if it does not:
NodeID
must be assigned for every
node.
DataDir
must be specified for
each management and data node, and the data
directories for different nodes cannot overlap with
each other.
A “free” API node not bounded to any host must be provisioned, through which the mcmd agent can communicate with the cluster.
Create a MySQL user named mcmd
on
each SQL node, and grant root privileges to the user.
Make sure that the configuration cache is disabled for
each management node. Since the configuration cache is
enabled by default, unless the management node has been
started with the
--config-cache=false
option, you will need to stop and restart it with that
option, in addition to other options that it has been
started with previously.
Verify cluster process PID files.
Verify that each process in the “wild” cluster has a valid PID file.
If a given process does not have a valid PID file, you must create one for it.
See Section 4.5.2.2, “Verify All Cluster Process PID Files”, for a more detailed explanation and examples.
Create and configure “target” cluster under MySQL Cluster Manager control
Install MySQL Cluster Manager and start mcmd on all hosts with the same system user who started the wild cluster processes.
Create a MySQL Cluster Manager site encompassing these hosts, using the
create site
command.
Add a MySQL Cluster Manager package referencing the MySQL NDB Cluster binaries,
using the add package
command. Use this command's
--basedir
option to point to the
location of the MySQL NDB Cluster installation directory.
Create the target cluster using the
create
cluster
command, including the same processes
and hosts used by the wild cluster. Use the command's
--import
option to specify that the
cluster is a target for import.
If the wild cluster adheres to the recommendation for
node ID assignments given in the description for the
create
cluster
command, you need not specify the node
IDs for the processes in the
create
cluster
command.
Also, this step may be split into a
create
cluster
command followed by one or more
add process
commands
(see
Section 4.5.2.3, “Creating and Configuring the Target Cluster”).
For importing a cluster that uses TLS connections, perform the following steps (see TLS Link Encryption for NDB Cluster and Section 4.11, “Using TLS Connections for NDB Clusters” for details):
Copy a set of API certificates and its private key to the default certificate directory on every host for mcmd to use.
Set
--ndb-tls-search-path
for all the processes to the correct folders.
Set
RequireTls
,
RequireCertificate
,
and
--ndb-mgm-tls
for the processes to their respective values
Use import config
to
copy the wild cluster's configuration data into the
target cluster. Use this command's
--dryrun
option (short form: -y
) to perform a
test run that merely logs the configuration information
the command copies when it is executed without the
option.
If any ndb_mgmd
or
mysqld
processes in the wild cluster
are running on ports other than the default, you must
first perform set
commands to assign the correct port numbers for them in
the target cluster. When all such processes are running
on the correct ports and the dry run is successful, you
can execute import config
(without
the
--dryrun
option) to copy the wild cluster's configuration
data. Following this step, you should check the log as
well as the configuration of the target cluster to
ensure that all configuration attributes were copied
correctly and with the correct scope. Correct any
inconsistencies with the wild cluster's
configuration using the appropriate
set
commands.
Test and perform migration of wild cluster.
Perform a test run of the proposed migration using
import cluster
with the
--dryrun
option, which causes MySQL Cluster Manager to check for errors, but not
actually migrate any processes or data.
Correct any errors found using
--dryrun
.
Repeat the dry run from the previous step to ensure that
no errors were missed.
When the dry run no longer reports any errors, you can
perform the migration using import
cluster
, but without the
--dryrun
option.