New to KubeDB? Please start here.
Restart Memcached
KubeDB supports restarting the Memcached database via a MemcachedOpsRequest. Restarting is useful if some pods are got stuck in some phase, or they are not working correctly. This tutorial will show you how to use that.
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.
Now, install KubeDB cli on your workstation and KubeDB operator in your cluster following the steps here.
To keep things isolated, this tutorial uses a separate namespace called
demothroughout this tutorial.
$ kubectl create ns demo
namespace/demo created
Note: YAML files used in this tutorial are stored in docs/examples/memcached folder in GitHub repository kubedb/docs.
Deploy Memcached
In this section, we are going to deploy a Memcached database using KubeDB.
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/v2025.3.24/docs/examples/memcached/restart/memcached.yaml
memcached.kubedb.com/memcd-quickstart created
Apply Restart opsRequest
apiVersion: ops.kubedb.com/v1alpha1
kind: MemcachedOpsRequest
metadata:
name: restart
namespace: demo
spec:
type: Restart
databaseRef:
name: memcd-quickstart
spec.typespecifies the Type of the ops Requestspec.databaseRefholds the name of the Memcached database. The database should be available in the same namespace as the opsRequest- The meaning of
spec.timeout&spec.applyfields can be found here
Let’s create the MemcachedOpsRequest CR we have shown above:
$ kubectl create -f https://github.com/kubedb/docs/raw/v2025.3.24/docs/examples/memcached/restart/opsrequest-restart.yaml
memcachedopsrequest.ops.kubedb.com/restart created
Now the Ops-manager operator will first restart the pods one by one.
$ kubectl get mcops -n demo restart
NAME TYPE STATUS AGE
restart Restart Successful 3m25s
$ kubectl get mcops -n demo restart -oyaml
apiVersion: ops.kubedb.com/v1alpha1
kind: MemcachedOpsRequest
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"ops.kubedb.com/v1alpha1","kind":"MemcachedOpsRequest","metadata":{"annotations":{},"name":"restart","namespace":"demo"},"spec":{"databaseRef":{"name":"memcd-quickstart"},"type":"Restart"}}
creationTimestamp: "2024-11-13T13:13:42Z"
generation: 1
name: restart
namespace: demo
resourceVersion: "1740073"
uid: dbe5f074-f894-4c89-b34f-a4fad2322576
spec:
apply: IfReady
databaseRef:
name: memcd-quickstart
type: Restart
status:
conditions:
- lastTransitionTime: "2024-11-13T13:13:42Z"
message: Memcached ops request is restarting the database nodes
observedGeneration: 1
reason: Restart
status: "True"
type: Restart
- lastTransitionTime: "2024-11-13T13:13:52Z"
message: Successfully restarted pods
observedGeneration: 1
reason: RestartPods
status: "True"
type: RestartPods
- lastTransitionTime: "2024-11-13T13:13:47Z"
message: evict pod; ConditionStatus:True; PodName:memcd-quickstart-0
observedGeneration: 1
status: "True"
type: EvictPod--memcd-quickstart-0
- lastTransitionTime: "2024-11-13T13:13:47Z"
message: is pod ready; ConditionStatus:False
observedGeneration: 1
status: "False"
type: IsPodReady
- lastTransitionTime: "2024-11-13T13:13:52Z"
message: is pod ready; ConditionStatus:True; PodName:memcd-quickstart-0
observedGeneration: 1
status: "True"
type: IsPodReady--memcd-quickstart-0
- lastTransitionTime: "2024-11-13T13:13:52Z"
message: Successfully Restarted Database
observedGeneration: 1
reason: Successful
status: "True"
type: Successful
observedGeneration: 1
phase: Successful
Cleaning up
To cleanup the Kubernetes resources created by this tutorial, run:
kubectl delete memcachedopsrequest -n demo restart
kubectl delete memcached -n demo memcd-quickstart
kubectl delete ns demo
Next Steps
- Monitor your Memcached database with KubeDB using Built-in Prometheus.
- Monitor your Memcached database with KubeDB using Prometheus Operator.
- Detail concepts of Memcached.
- Use private Docker registry to deploy Memcached with KubeDB.
- Want to hack on KubeDB? Check our contribution guidelines.