Making changes in the configuration of an NDB Cluster running in
Kubernetes, requires editing the
NdbCluster YAML spec file, then
applying the updated file to the Kubernetes Cluster.
Consider the example
from the file
(see Section 3.1, “Setting the NDB Cluster's Configuration”), which provides
two SQL nodes. To increase this number to five, update
spec.mysqld.nodeCount in this file to the
preferred value. The updated file should look like what is shown
here (with the edited line in highlighted text):
apiVersion: mysql.oracle.com/v1 kind: NdbCluster metadata: name: example-ndb spec: redundancyLevel: 2 dataNode: nodeCount: 2 mysqlNode: nodeCount: 5
Now you can apply the updated YAML file to the Kubernetes Cluster, like this:
> kubectl apply -f docs/examples/example-ndb.yaml ndbclusters.mysql.oracle.com/example-ndb configured
Once the change has been applied, NDB Operator picks up the changes and begins applying them to the NDB Cluster. In this particular case, it updates the management node configuration files, performs a rolling restart (see Performing a Rolling Restart of an NDB Cluster), and starts additional mysqld processes (SQL nodes).
The status and readiness of the NDB Cluster nodes can be observed as when they were first deployed.