How to Run HA MySQL on IBM Cloud Kubernetes Service

This post is part of our ongoing series on running MySQL on Kubernetes.  We’ve published a number of articles about running MySQL on Kubernetes for specific platforms and for specific use cases.  If you are looking for a specific Kubernetes platform, check out these related articles.

Running HA MySQL on Azure Kubernetes Service (AKS)

Running HA MySQL on Google Kubernetes Engine (GKE)

Running HA MySQL on Amazon Elastic Container Service for Kubernetes (EKS)

Running HA MySQL on Red Hat OpenShift

Running HA MySQL on Rancher Kubernetes Engine (RKE)

How to Backup and Restore MySQL on Red Hat OpenShift

Running HA MySQL on IBM Cloud Private

Kubernetes Persistent Volume Tutorial by Portworx

Databases on Kubernetes

And now, onto the post…

IBM Cloud Kubernetes Service is a managed Kubernetes offering running in IBM Cloud. It is designed to deliver powerful tools, intuitive user experience, and built-in security for rapid delivery of applications that can be bound to cloud services related to IBM Watson, IoT, DevOps, and data analytics. As a CNCF-certified Kubernetes provider, IBM Cloud Kubernetes Service provides intelligent scheduling, self-healing, horizontal scaling, service discovery and load balancing, automated rollouts and rollbacks, and secret and configuration management. The service also has advanced capabilities around simplified cluster management, container security, and isolation policies, the ability to design a cluster with a custom configuration and integrated operational tools for consistency in deployment.

Portworx is a Kubernetes storage and data management platform that enables enterprises to confidently run mission-critical data services on IBM Cloud Kubernetes Service (as well as IBM Cloud Private). The addition of primitives (such as stateful sets and persistent volumes) to Kubernetes has made it possible, in theory, to run stateful services like databases on Kubernetes. But, these primitives alone do not address the core business challenges associated with running data-rich applications on Kubernetes: high availability, backup and recovery, data security, SLA-management, and more. Portworx provides a single data-management layer for all stateful services that directly addresses these challenging topics.

I’m really excited to work with Portworx and Janakiram MSV (@janakiramm), architect and advisor with Portworx, on this tutorial. The rest of the blog was authored by Jani.

Tutorial

This tutorial is a walk-through of the steps involved in deploying and managing a highly available MySQL cluster on IBM Cloud Kubernetes Service (IKS).

In summary, to run HA MySQL on IKS you need to:

• Launch an IKS cluster running on bare metal servers with software-defined storage (SDS)
• Install cloud native storage solution like Portworx as a Daemonset on IKS
• Create a storage class defining your storage requirements like replication factor, snapshot policy, and performance profile
• Deploy MySQL using Kubernetes
• Test failover by killing or cordoning node in your cluster
• Expanding the volume size dynamically
• Perform backup and restore through snapshots

Launching an IKS Cluster

For running stateful workloads in a production environment backed by Portworx, it is highly recommended to launch an IKS cluster based on bare metal servers and software-defined storage. The minimum requirements of a worker node to successfully run Portworx include:

• 4 CPU cores
• 4GB memory
• 128GB of raw unformatted storage
• 10Gbps network speed

For details on launching a Kubernetes cluster with bare metal worker nodes, please refer to the documentation of IBM Cloud Kubernetes Service.

We are using an IKS cluster with 4 nodes out of which 3 nodes are running bare metal servers with SDS based on the instance type ms2c.4x32.1.9tb.ssd.encrypted. Only these machines that meet the prerequisite would be used by Portworx.

When we filter the nodes based on the label, we see the below nodes:

$ kubectl get nodes -l beta.kubernetes.io/instance-type=ms2c.4x32.1.9tb.ssd.encrypted
NAME           STATUS   ROLES    AGE    VERSION
10.177.26.18   Ready    <none>   4d7h   v1.13.2+IKS
10.185.22.28   Ready    <none>   4d7h   v1.13.2+IKS
10.73.90.131   Ready    <none>   4d3h   v1.13.2+IKS

To exclude nodes that don’t meet Portworx prerequisites, you can apply a label to skip the installation of Portworx. For example, the below command applies a label on the node with name 10.185.22.14 which doesn’t run on a bare metal server.

$ kubectl label nodes 10.185.22.14  px/enabled=false --overwrite

Installing Portworx in IKS

Installing Portworx on IKS is not very different from installing it on any other Kubernetes cluster. It is recommended that you create an etcd instance through Compose for etcd. You can use the Helm Chart to install Portworx cluster in IKS. Portworx documentation for IKS has the prerequisites and instructions to install and configure Portworx, STORK, and other components.

At the end of the installation, we will have Portworx Daemonset running on the nodes excluding those that are filtered out in the previous step.

Once the IKS cluster is up and running, and Portworx is installed and configured, we will deploy a highly available MySQL database.

Creating a Kubernetes storage class for MySQL

Once the IKS cluster is up and running, and Portworx is installed and configured, we will deploy a highly available MySQL database.

Through Kubernetes storage class objects, an admin can define different classes of Portworx volumes that are offered in a cluster. These classes will be used during the dynamic provisioning of volumes. The Storage Class defines the replication factor, I/O profile (e.g., for a database or a CMS), and priority (e.g., SSD or HDD). These parameters impact the availability and throughput of workloads and can be specified for each volume. This is important because a production database will have different requirements than a development Jenkins cluster.

In this example, the storage class that we deploy has a replication factor of 3 with I/O profile set to “db,” and priority set to “high.” This means that the storage will be optimized for low latency database workloads like MySQL and automatically placed on the highest performance storage available in the cluster. Notice that we also mention the filesystem, xfs in the storage class.

$ cat > px-mysql-sc.yaml << EOF
kind: StorageClass
apiVersion: storage.k8s.io/v1beta1
metadata:
    name: px-ha-sc
provisioner: kubernetes.io/portworx-volume
parameters:
  repl: "3"
  io_profile: "db_remote"
  priority_io: "high"
  fs: "xfs"
EOF

$ kubectl create -f px-mysql-sc.yaml
storageclass.storage.k8s.io "px-ha-sc" created

$ kubectl get sc
NAME                         PROVISIONER                     AGE
default                      ibm.io/ibmc-file                7d2h
ibmc-file-bronze (default)   ibm.io/ibmc-file                7d2h
ibmc-file-custom             ibm.io/ibmc-file                7d2h
ibmc-file-gold               ibm.io/ibmc-file                7d2h
ibmc-file-retain-bronze      ibm.io/ibmc-file                7d2h
ibmc-file-retain-custom      ibm.io/ibmc-file                7d2h
ibmc-file-retain-gold        ibm.io/ibmc-file                7d2h
ibmc-file-retain-silver      ibm.io/ibmc-file                7d2h
ibmc-file-silver             ibm.io/ibmc-file                7d2h
portworx-db-sc               kubernetes.io/portworx-volume   3m54s
portworx-db2-sc              kubernetes.io/portworx-volume   3m54s
portworx-null-sc             kubernetes.io/portworx-volume   3m54s
portworx-shared-sc           kubernetes.io/portworx-volume   3m54s
px-ha-sc                     kubernetes.io/portworx-volume   9s
stork-snapshot-sc            stork-snapshot                  3m54s

Creating a MySQL PVC on Kubernetes

We can now create a Persistent Volume Claim (PVC) based on the Storage Class. Thanks to dynamic provisioning, the claims will be created without explicitly provisioning Persistent Volume (PV).

$ cat > px-mysql-pvc.yaml << EOF
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
   name: px-mysql-pvc
   annotations:
     volume.beta.kubernetes.io/storage-class: px-ha-sc
spec:
   accessModes:
     - ReadWriteOnce
   resources:
     requests:
       storage: 1Gi
EOF

$ kubectl create -f px-mysql-pvc.yaml
persistentvolumeclaim/px-mysql-pvc created

$ kubectl get pvc
NAME           STATUS    VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
px-mysql-pvc   Bound    pvc-909a51d5-31a3-11e9-aa17-32e4785d9ba0   1Gi        RWO            px-ha-sc       8s

Deploying MySQL on IKS

Finally, let’s create a MySQL instance as a Kubernetes deployment object. For simplicity’s sake, we will just be deploying a single MySQL pod. Because Portworx provides synchronous replication for High Availability, a single MySQL instance might be the best deployment option for your MySQL database. Portworx can also provide backing volumes for multi-node MySQL cluster. The choice is yours.

$ cat > px-mysql-app.yaml << EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
spec:
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 1
    type: RollingUpdate
  replicas: 1
  selector:
    matchLabels:
      app: mysql  
  template:
    metadata:
      labels:
        app: mysql
    spec:
      schedulerName: stork
      containers:
      - name: mysql
        image: mysql:5.6
        imagePullPolicy: "Always"
        env:
        - name: MYSQL_ROOT_PASSWORD
          value: password        
        ports:
        - containerPort: 3306
        volumeMounts:
        - mountPath: /var/lib/mysql
          name: mysql-data
      volumes:
      - name: mysql-data
        persistentVolumeClaim:
          claimName: px-mysql-pvc
EOF

$ kubectl create -f px-mysql-app.yaml
deployment.extensions/mysql created

The MySQL deployment defined above is explicitly associated with the PVC, px-mysql-pvc created in the previous step.
This deployment creates a single pod running MySQL backed by Portworx.

$ kubectl get pods
NAME                     READY     STATUS    RESTARTS   AGE
mysql-76d5c4b78b-hqjcs   1/1     Running   0          14s

We can inspect the Portworx volume by accessing the pxctl tool running with the MySQL pod.

$ VOL=`kubectl get pvc | grep px-mysql-pvc | awk '{print $3}'`
$ PX_POD=$(kubectl get pods -l name=portworx -n kube-system -o jsonpath='{.items[0].metadata.name}')
$ kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume inspect ${VOL}
Volume	:  781585151816423188
	Name            	 :  pvc-909a51d5-31a3-11e9-aa17-32e4785d9ba0
	Size            	 :  1.0 GiB
	Format          	 :  ext4
	HA              	 :  3
	IO Priority     	 :  LOW
	Creation time   	 :  Feb 16 04:30:18 UTC 2019
	Shared          	 :  no
	Status          	 :  up
	State           	 :  Attached: 6ab3face-615f-4cc7-bcfa-a1872d006e34 (10.185.22.29)
	Device Path     	 :  /dev/pxd/pxd781585151816423188
	Labels          	 :  namespace=default,pvc=px-mysql-pvc
	Reads           	 :  12
	Reads MS        	 :  36
	Bytes Read      	 :  49152
	Writes          	 :  609
	Writes MS       	 :  10256
	Bytes Written   	 :  146239488
	IOs in progress 	 :  0
	Bytes used      	 :  10 MiB
	Replica sets on nodes:
		Set 0
		  Node 		 : 10.73.90.131 (Pool 0)
		  Node 		 : 10.177.26.18 (Pool 0)
		  Node 		 : 10.185.22.29 (Pool 0)
	Replication Status	 :  Up
	Volume consumers	 :
		- Name           : mysql-76d5c4b78b-hqjcs (bb30c604-31a3-11e9-930d-4e511e6b17c9) (Pod)
		  Namespace      : default
		  Running on     : 10.185.22.29
		  Controlled by  : mysql-76d5c4b78b (ReplicaSet)

The output from the above command confirms the creation of volumes that are backing MySQL database instance.

Failing over MySQL pod on Kubernetes

Populating sample data

Let’s populate the database with some sample data.
We will first find the pod that’s running MySQL to access the shell.

$ POD=`kubectl get pods -l app=mysql | grep Running | grep 1/1 | awk '{print $1}'`

$ kubectl exec -it $POD -- mysql -uroot -ppassword
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.40 MySQL Community Server (GPL)

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

Now that we are inside the shell, we can populate create a sample database and table.

mysql> CREATE DATABASE `classicmodels`;

mysql> USE `classicmodels`;

mysql> CREATE TABLE `offices` (
  `officeCode` varchar(10) NOT NULL,
  `city` varchar(50) NOT NULL,
  `phone` varchar(50) NOT NULL,
  `addressLine1` varchar(50) NOT NULL,
  `addressLine2` varchar(50) DEFAULT NULL,
  `state` varchar(50) DEFAULT NULL,
  `country` varchar(50) NOT NULL,
  `postalCode` varchar(15) NOT NULL,
  `territory` varchar(10) NOT NULL,
  PRIMARY KEY (`officeCode`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

mysql> insert  into `offices`(`officeCode`,`city`,`phone`,`addressLine1`,`addressLine2`,`state`,`country`,`postalCode`,`territory`) values 
('1','San Francisco','+1 650 219 4782','100 Market Street','Suite 300','CA','USA','94080','NA'),
('2','Boston','+1 215 837 0825','1550 Court Place','Suite 102','MA','USA','02107','NA'),
('3','NYC','+1 212 555 3000','523 East 53rd Street','apt. 5A','NY','USA','10022','NA'),
('4','Paris','+33 14 723 4404','43 Rue Jouffroy D\'abbans',NULL,NULL,'France','75017','EMEA'),
('5','Tokyo','+81 33 224 5000','4-1 Kioicho',NULL,'Chiyoda-Ku','Japan','102-8578','Japan'),
('6','Sydney','+61 2 9264 2451','5-11 Wentworth Avenue','Floor #2',NULL,'Australia','NSW 2010','APAC'),
('7','London','+44 20 7877 2041','25 Old Broad Street','Level 7',NULL,'UK','EC2N 1HN','EMEA');

Let’s run a few queries on the table.

mysql> select `officeCode`,`city`,`phone`,`addressLine1`,`city` from `offices`;
+------------+---------------+------------------+--------------------------+---------------+
| officeCode | city          | phone            | addressLine1             | city          |
+------------+---------------+------------------+--------------------------+---------------+
| 1          | San Francisco | +1 650 219 4782  | 100 Market Street        | San Francisco |
| 2          | Boston        | +1 215 837 0825  | 1550 Court Place         | Boston        |
| 3          | NYC           | +1 212 555 3000  | 523 East 53rd Street     | NYC           |
| 4          | Paris         | +33 14 723 4404  | 43 Rue Jouffroy D'abbans | Paris         |
| 5          | Tokyo         | +81 33 224 5000  | 4-1 Kioicho              | Tokyo         |
| 6          | Sydney        | +61 2 9264 2451  | 5-11 Wentworth Avenue    | Sydney        |
| 7          | London        | +44 20 7877 2041 | 25 Old Broad Street      | London        |
+------------+---------------+------------------+--------------------------+---------------+
7 rows in set (0.01 sec)

Find all the offices in the USA.

mysql> select `officeCode`, `city`, `phone`  from `offices` where `country` = "USA";
+------------+---------------+-----------------+
| officeCode | city          | phone           |
+------------+---------------+-----------------+
| 1          | San Francisco | +1 650 219 4782 |
| 2          | Boston        | +1 215 837 0825 |
| 3          | NYC           | +1 212 555 3000 |
+------------+---------------+-----------------+
3 rows in set (0.00 sec)

Exit from the MySQL shell to return to the host.

Simulating node failure

Now, let’s simulate the node failure by cordoning off the node on which MySQL is running.

$ NODE=`kubectl get pods -l app=mysql -o wide | grep -v NAME | awk '{print $7}'`

$ kubectl cordon ${NODE}
node/10.185.22.29 cordoned

The above command disabled scheduling on one of the nodes.

$ kubectl get nodes
NAME                                            STATUS                     ROLES     AGE       VERSION
NAME           STATUS                     ROLES    AGE     VERSION
10.177.26.18   Ready                         8d      v1.13.2+IKS
10.185.22.14   Ready                         8d      v1.13.2+IKS
10.185.22.29   Ready,SchedulingDisabled      6h48m   v1.13.2+IKS
10.73.90.131   Ready                         8d      v1.13.2+IKS

Now, let’s go ahead and delete the MySQL pod.

$ POD=`kubectl get pods -l app=mysql -o wide | grep -v NAME | awk '{print $1}'`
$ kubectl delete pod ${POD}
pod "mysql-76d5c4b78b-hqjcs" deleted

As soon as the pod is deleted, it is relocated to the node with the replicated data. STorage ORchestrator for Kubernetes (STORK), Portworx’s custom storage scheduler allows co-locating the pod on the exact node where the data is stored. It ensures that an appropriate node is selected for scheduling the pod.

Let’s verify this by running the below command. We will notice that a new pod has been created and scheduled in a different node.

$ kubectl get pods -l app=mysql -o wide
NAME                     READY   STATUS    RESTARTS   AGE   IP             NODE           NOMINATED NODE   READINESS GATES
mysql-76d5c4b78b-vgwk6   1/1     Running   0          17s   172.30.59.91   10.177.26.18              

$ kubectl uncordon ${NODE}
node/10.185.22.29 uncordoned

Finally, let’s verify that the data is still available.

Verifying that the data is intact

Let’s find the pod name and run the ‘exec’ command, and then access the MySQL shell.

$ POD=`kubectl get pods -l app=mysql -o wide | grep -v NAME | awk '{print $1}'`
$ kubectl exec -it $POD -- mysql -uroot -ppassword
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.40 MySQL Community Server (GPL)

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

We will query the database to verify that the data is intact.

mysql> USE `classicmodels`;
mysql> select `officeCode`, `city`, `phone`  from `offices` where `country` = "USA";
+------------+---------------+-----------------+
| officeCode | city          | phone           |
+------------+---------------+-----------------+
| 1          | San Francisco | +1 650 219 4782 |
| 2          | Boston        | +1 215 837 0825 |
| 3          | NYC           | +1 212 555 3000 |
+------------+---------------+-----------------+
3 rows in set (0.00 sec)

Observe that the database table is still there and all the content is intact! Exit from the client shell to return to the host.

Performing Storage Operations on MySQL

After testing end-to-end failover of the database, let’s perform StorageOps on our IKS cluster.

Expanding the Kubernetes Volume with no downtime

Currently, the Portworx volume that we created at the beginning is of 1Gib size. We will now expand it to double the storage capacity.

First, let’s get the volume name and inspect it through the pxctl tool.

$ VOL=`kubectl get pvc | grep px-mysql-pvc | awk '{print $3}'`
$ PX_POD=$(kubectl get pods -l name=portworx -n kube-system -o jsonpath='{.items[0].metadata.name}')
$ kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume inspect ${VOL}
Volume	:  781585151816423188
	Name            	 :  pvc-909a51d5-31a3-11e9-aa17-32e4785d9ba0
	Size            	 :  1.0 GiB
	Format          	 :  ext4
	HA              	 :  3
	IO Priority     	 :  LOW
	Creation time   	 :  Feb 16 04:30:18 UTC 2019
	Shared          	 :  no
	Status          	 :  up
	State           	 :  Attached: d7f53ebb-0d02-4ba4-b689-2f335e8f9379 (10.177.26.18)
	Device Path     	 :  /dev/pxd/pxd781585151816423188
	Labels          	 :  namespace=default,pvc=px-mysql-pvc
	Reads           	 :  178
	Reads MS        	 :  400
	Bytes Read      	 :  6422528
	Writes          	 :  26
	Writes MS       	 :  164
	Bytes Written   	 :  294912
	IOs in progress 	 :  0
	Bytes used      	 :  17 MiB
	Replica sets on nodes:
		Set 0
		  Node 		 : 10.73.90.131 (Pool 0)
		  Node 		 : 10.177.26.18 (Pool 0)
		  Node 		 : 10.185.22.29 (Pool 0)
	Replication Status	 :  Up
	Volume consumers	 :
		- Name           : mysql-76d5c4b78b-vgwk6 (b1094e0f-31a4-11e9-930d-4e511e6b17c9) (Pod)
		  Namespace      : default
		  Running on     : 10.177.26.18
		  Controlled by  : mysql-76d5c4b78b (ReplicaSet)

Notice the current Portworx volume. It is 1GiB. Let’s expand it to 2GiB.

$ kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume update $VOL --size=2
Update Volume: Volume update successful for volume pvc-909a51d5-31a3-11e9-aa17-32e4785d9ba0

Check the new volume size.

kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume inspect ${VOL}
Volume	:  781585151816423188
	Name            	 :  pvc-909a51d5-31a3-11e9-aa17-32e4785d9ba0
	Size            	 :  2.0 GiB
	Format          	 :  ext4
	HA              	 :  3
	IO Priority     	 :  LOW
	Creation time   	 :  Feb 16 04:30:18 UTC 2019
	Shared          	 :  no
	Status          	 :  up
	State           	 :  Attached: d7f53ebb-0d02-4ba4-b689-2f335e8f9379 (10.177.26.18)
	Device Path     	 :  /dev/pxd/pxd781585151816423188
	Labels          	 :  namespace=default,pvc=px-mysql-pvc
	Reads           	 :  253
	Reads MS        	 :  624
	Bytes Read      	 :  6729728
	Writes          	 :  46
	Writes MS       	 :  280
	Bytes Written   	 :  1212416
	IOs in progress 	 :  0
	Bytes used      	 :  17 MiB
	Replica sets on nodes:
		Set 0
		  Node 		 : 10.73.90.131 (Pool 0)
		  Node 		 : 10.177.26.18 (Pool 0)
		  Node 		 : 10.185.22.29 (Pool 0)
	Replication Status	 :  Up
	Volume consumers	 :
		- Name           : mysql-76d5c4b78b-vgwk6 (b1094e0f-31a4-11e9-930d-4e511e6b17c9) (Pod)
		  Namespace      : default
		  Running on     : 10.177.26.18
		  Controlled by  : mysql-76d5c4b78b (ReplicaSet)

Taking Snapshots of a Kubernetes volume and restoring the database

Portworx supports creating snapshots for Kubernetes PVCs.
Let’s create a snapshot for the Kubernetes PVC we created for MySQL.

cat >  px-mysql-snap.yaml << EOF
apiVersion: volumesnapshot.external-storage.k8s.io/v1
kind: VolumeSnapshot
metadata:
  name: px-mysql-snapshot
  namespace: default
spec:
  persistentVolumeClaimName: px-mysql-pvc
EOF

$ kubectl create -f px-mysql-snap.yaml
volumesnapshot.volumesnapshot.external-storage.k8s.io/px-mysql-snapshot created

Verify the creation of volume snapshot.

$ kubectl get volumesnapshot
NAME                AGE
px-mysql-snapshot   30s

$ kubectl get volumesnapshotdatas
NAME                                                       AGE
k8s-volume-snapshot-ce24471e-31a5-11e9-993d-eaa7125cd4d9   41s

With the snapshot in place, let’s go ahead and delete the database.

$ POD=`kubectl get pods -l app=mysql | grep Running | grep 1/1 | awk '{print $1}'`
$ kubectl exec -it $POD -- mysql -uroot -ppassword

drop database classicmodels;

Since snapshots are just like volumes, we can use it to start a new instance of MySQL. Let’s create a new instance of MySQL by restoring the snapshot data.

$ cat > px-mysql-snap-pvc << EOF
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: px-mysql-snap-clone
  annotations:
    snapshot.alpha.kubernetes.io/snapshot: px-mysql-snapshot
spec:
  accessModes:
     - ReadWriteOnce
  storageClassName: stork-snapshot-sc
  resources:
    requests:
      storage: 2Gi
EOF

$ kubectl create -f px-mysql-snap-pvc.yaml
persistentvolumeclaim/px-mysql-snap-clone created

From the new PVC, we will create a MySQL pod.

$ cat < px-mysql-snap-restore.yaml >> EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql-snap
spec:
  selector:
    matchLabels:
      app: mysql-snap
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 1
    type: RollingUpdate
  replicas: 1
  template:
    metadata:
      labels:
        app: mysql-snap
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: px/running
                operator: NotIn
                values:
                - "false"
              - key: px/enabled
                operator: NotIn
                values:
                - "false"
    spec:
      containers:
      - name: mysql
        image: mysql:5.6
        imagePullPolicy: "Always"
        env:
        - name: MYSQL_ROOT_PASSWORD
          value: password       
        ports:
        - containerPort: 3306
        volumeMounts:
        - mountPath: /var/lib/mysql
          name: mysql-data
      volumes:
      - name: mysql-data
        persistentVolumeClaim:
          claimName: px-mysql-snap-clone
EOF

$ kubectl create -f px-mysql-snap-restore.yaml
deployment.extensions/mysql-snap created

Verify that the new pod is in a Running state.

$ kubectl get pods -l app=mysql-snap
NAME                         READY     STATUS    RESTARTS   AGE
mysql-snap-9bb86fd6b-xpttx   1/1     Running   0          14s

Finally, let’s access the sample data created earlier in the walk-through.

$ POD=`kubectl get pods -l app=mysql-snap | grep Running | grep 1/1 | awk '{print $1}'`
$ kubectl exec -it $POD -- mysql -uroot -ppassword
mysql> USE `classicmodels`;
mysql> select `officeCode`, `city`, `phone`  from `offices` where `country` = "USA";
+------------+---------------+-----------------+
| officeCode | city          | phone           |
+------------+---------------+-----------------+
| 1          | San Francisco | +1 650 219 4782 |
| 2          | Boston        | +1 215 837 0825 |
| 3          | NYC           | +1 212 555 3000 |
+------------+---------------+-----------------+
3 rows in set (0.00 sec)

Notice that the collection is still there with the data intact. We can also push the snapshot to an Amazon S3-compatible object storage service if we want to create a disaster recovery backup in another region or location. Since Portworx snapshots work with any S3 compatible object storage, the backup can go to a different cloud or even an on-premises data center.

Summary

Portworx can be easily deployed on IBM Cloud Kubernetes Service to run stateful workloads in production. Through the integration of STORK, DevOps and StorageOps teams can seamlessly run highly available database clusters in IKS. They can perform traditional operations such as volume expansion, backup, and recovery for the cloud native applications in an automated and efficient manner.