This tutorial demonstrates how to deploy the RadonDB MySQL Operator and cluster offline on Kubernetes.

Prerequisite

• You need to prepare an available Kubernetes cluster.

Procedure

Step 1 Prepare resources.

• Download offline resources.

  Download the images radondb/mysql-operator, radondb/mysql57-sidecar, radondb/mysql80-sidercar, percona/percona-server:5.7.34, and percona/percona-server:8.0.25 from Docker Hub and load them to available worker nodes.

• Import images (on each worker node).

  docker load -i XXXX
  

  Please replace XXXX with the names of the downloaded image files.

Step 2 Deploy RadonDB MySQL Operator.

The following sets the release name to demo, and creates a Deployment named demo-mysql-operator.

helm install demo radondb-mysql-resources/operator-chart .

Note

By default, this step will also create the custom resource required by the cluster. You can find the corresponding release.

Step 3 Deploy the RadonDB MySQL cluster.

The following creates an instance for the custom resource mysqlclusters.mysql.radondb.com, and thereby create a RadonDB MySQL cluster with the default parameters. To configure cluster parameters, see Parameter Configuration.

kubectl apply -f radondb-mysql-resources/cluster-sample/mysql_v1alpha1_mysqlcluster.yaml

Verification

Verify RadonDB MySQL Operator

Check the demo Deployment and its monitoring service as follows. The deployment is successful if the following information is displayed.

$ kubectl get deployment,svc
NAME                  READY   UP-TO-DATE   AVAILABLE   AGE
demo-mysql-operator   1/1     1            1           7h50m


NAME                             TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
service/mysql-operator-metrics   ClusterIP   10.96.142.22    <none>        8443/TCP   8h

Verify the RadonDB MySQL cluster

Check the CRDs as follows.

$ kubectl get crd | grep mysql.radondb.com
backups.mysql.radondb.com                             2021-11-02T07:00:01Z
mysqlclusters.mysql.radondb.com                       2021-11-02T07:00:01Z
mysqlusers.mysql.radondb.com                          2021-11-02T07:00:01Z

For the default deployment, run the following command to check the cluster, and a statefulset of three replicas (RadonDB MySQL nodes) and services used to access the nodes are displayed.

$ kubectl get statefulset,svc
NAME           READY   AGE
sample-mysql   3/3     7h33m

NAME                             TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
service/sample-follower          ClusterIP   10.96.131.84    <none>        3306/TCP   7h37m
service/sample-leader            ClusterIP   10.96.111.214   <none>        3306/TCP   7h37m
service/sample-mysql             ClusterIP   None            <none>        3306/TCP   7h37m

Access RadonDB MySQL

You need to prepare a client used to connect to MySQL.

RadonDB MySQL provides the leader and follower services to access the leader node and replicas respectively. The leader service always points to the leader node (read/write) and the follower service points to the replicas (read only).

Within the Kubernertes cluster, you can use service_name or clusterIP to access RadonDB MySQL in the Kubernetes cluster.

By clusterIP

The HA clusterIP of the leader service supports reading and writing data, while the HA clusterIP of the follower service supports reading data only.

mysql -h <clusterIP> -P <mysql_Port> -u <user_name> -p

For example, run the following command to access the leader service with the username radondb_usr and IP address of the leader service 10.10.128.136:

mysql -h 10.10.128.136 -P 3306 -u radondb_usr -p

By service name

• Access the leader service (RadonDB MySQL leader node).

  mysql -h <leader_service_name>.<namespace> -u <user_name> -p
  

  For example, run the following command to access the leader service, with the username radondb_usr, release name sample, and namespace of RadonDB MySQL default:

  mysql -h sample-leader.default -u radondb_usr -p
  

• Access the follower service (RadonDB MySQL replicas)

  mysql -h <follower_service_name>.<namespace> -u <user_name> -p
  

  For example, run the following command to access the follower service with the username radondb_usr, release name sample, and namespace of RadonDB MySQL is default:

  mysql -h sample-follower.default -u radondb_usr -p  
  

Note

If the client is installed in a different Kubernetes cluster, see Access Applications in a Cluster to configure port forwarding and load balancing.

Uninstallation

Uninstall RadonDB MySQL Operator

Uninstall the demo Operator in the current namespace as follows.

helm delete demo

Uninstall the RadonDB MySQL cluster

Uninstall the sample cluster as follows.

kubectl delete mysqlclusters.mysql.radondb.com sample

Uninstall custom resources

kubectl delete customresourcedefinitions.apiextensions.k8s.io mysqlclusters.mysql.radondb.com
kubectl delete customresourcedefinitions.apiextensions.k8s.io mysqlusers.mysql.radondb.com
kubectl delete customresourcedefinitions.apiextensions.k8s.io backups.mysql.radondb.com