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Update version of Memcached

This guide will show you how to use KubeDB Enterprise operator to update the version of Memcached.

Before You Begin

• At first, you need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using kind.

• Install KubeDB Community and Enterprise operator in your cluster following the steps here.

• You should be familiar with the following KubeDB concepts:

  • Memcached
  • MemcachedOpsRequest
  • updating Overview

To keep everything isolated, we are going to use a separate namespace called demo throughout this tutorial.

$ kubectl create ns demo
namespace/demo created

Note: YAML files used in this tutorial are stored in docs/examples/memcached directory of kubedb/docs repository.

Prepare Memcached Database

Now, we are going to deploy a Memcached database with version 1.6.22.

Deploy Memcached:

In this section, we are going to deploy a Memcached database. Then, in the next section we will update the version of the database using MemcachedOpsRequest CRD. Below is the YAML of the Memcached CR that we are going to create,

apiVersion: kubedb.com/v1
kind: Memcached
metadata:
  name: memcd-quickstart
  namespace: demo
spec:
  replicas: 1
  version: "1.6.22"
  podTemplate:
    spec:
      containers:
        - name: memcached
          resources:
            limits:
              cpu: 500m
              memory: 128Mi
            requests:
              cpu: 250m
              memory: 64Mi
  deletionPolicy: WipeOut

Let’s create the Memcached CR we have shown above,

$ kubectl create -f https://github.com/kubedb/docs/raw/v2025.8.31/docs/examples/memcached/update-version/memcached.yaml
memcached.kubedb.com/memcd-quickstart created

Now, wait until memcd-quickstart created has status Ready. i.e,

$ kubectl get mc -n demo
NAME               VERSION   STATUS   AGE
memcd-quickstart   1.6.22    Ready    3m

We are now ready to apply the MemcachedOpsRequest CR to update this database.

Update Memcached Version

Here, we are going to update Memcached sdatabase from 1.6.22 to 1.6.29.

Create MemcachedOpsRequest:

In order to update the memcached database, we have to create a MemcachedOpsRequest CR with your desired version that is supported by KubeDB. Below is the YAML of the MemcachedOpsRequest CR that we are going to create,

apiVersion: ops.kubedb.com/v1alpha1
kind: MemcachedOpsRequest
metadata:
  name: update-memcd
  namespace: demo
spec:
  type: UpdateVersion
  databaseRef:
    name: memcd-quickstart
  updateVersion:
    targetVersion: 1.6.29

Here,

• spec.databaseRef.name specifies that we are performing operation on memcd-quickstart Memcached database.
• spec.type specifies that we are going to perform UpdateVersion on our database.
• spec.updateVersion.targetVersion specifies the expected version of the database 1.6.29.

Let’s create the MemcachedOpsRequest CR we have shown above,

$ kubectl apply -f https://github.com/kubedb/docs/raw/v2025.8.31/docs/examples/memcached/update-version/opsrequest-version-update.yaml
memcachedopsrequest.ops.kubedb.com/update-memcd created

Verify Memcached version updated successfully :

If everything goes well, KubeDB Enterprise operator will update the image of Memcached object and related PetSets and Pods.

Let’s wait for MemcachedOpsRequest to be Successful. Run the following command to watch MemcachedOpsRequest CR,

$ watch kubectl get memcachedopsrequest -n demo
Every 2.0s: kubectl get memcachedopsrequest -n demo
NAME           TYPE            STATUS       AGE
update-memcd   UpdateVersion   Successful   7m

We can see from the above output that the MemcachedOpsRequest has succeeded.

Now, we are going to verify whether the Memcached and the related PetSets their Pods have the new version image. Let’s check,

$ kubectl get memcached -n demo memcd-quickstart -o=jsonpath='{.spec.version}{"\n"}'
1.6.29

$ kubectl get petset -n demo memcd-quickstart -o=jsonpath='{.spec.template.spec.containers[0].image}{"\n"}'
ghcr.io/appscode-images/memcached:1.6.29-alpine

$ kubectl get pods -n demo memcd-quickstart-0 -o=jsonpath='{.spec.containers[0].image}{"\n"}'
ghcr.io/appscode-images/memcached:1.6.29-alpine

You can see from above, our Memcached database has been updated with the new version. So, the UpdateVersion process is successfully completed.

Cleaning Up

To clean up the Kubernetes resources created by this tutorial, run:

$ kubectl patch -n demo mc/memcd-quickstart -p '{"spec":{"deletionPolicy":"WipeOut"}}' --type="merge"
memcached.kubedb.com/memcd-quickstart patched

$ kubectl delete -n demo Memcached memcd-quickstart
memcached.kubedb.com "memcd-quickstart" deleted

$ kubectl delete -n demo memcachedopsrequest update-standalone
memcachedopsrequest.ops.kubedb.com "update-memcd" deleted