New to KubeDB? Please start here.
Reprovision MongoDB
KubeDB supports reprovisioning the MongoDB database via a MongoDBOpsRequest. Reprovisioning is useful if you want, for some reason, to deploy a new MongoDB with the same specifications. 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 demo throughout this tutorial.
$ kubectl create ns demo
namespace/demo created
Note: YAML files used in this tutorial are stored in docs/examples/mongodb folder in GitHub repository kubedb/docs.
Deploy MongoDB
In this section, we are going to deploy a MongoDB database using KubeDB.
apiVersion: kubedb.com/v1alpha2
kind: MongoDB
metadata:
name: mongo
namespace: demo
spec:
version: "4.4.26"
replicaSet:
name: "replicaset"
podTemplate:
spec:
resources:
requests:
cpu: "300m"
memory: "300Mi"
replicas: 2
storageType: Durable
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
terminationPolicy: WipeOut
arbiter: {}
hidden:
replicas: 2
storage:
storageClassName: "standard"
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 2Gi
spec.replicaSet represents the configuration for replicaset.name denotes the name of mongodb replicaset.
spec.replicas denotes the number of general members in rs0 mongodb replicaset.spec.podTemplate denotes specifications of all the 3 general replicaset members.spec.ephemeralStorage holds the emptyDir volume specifications. This storage spec will be passed to the StatefulSet created by KubeDB operator to run database pods. So, each members will have a pod of this ephemeral storage configuration.spec.arbiter denotes arbiter-node spec of the deployed MongoDB CRD.spec.hidden denotes hidden-node spec of the deployed MongoDB CRD.
Let’s create the MongoDB CR we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.3.16/docs/examples/mongodb/reprovision/mongo.yaml
mongodb.kubedb.com/mongo created
Apply Reprovision opsRequest
apiVersion: ops.kubedb.com/v1alpha1
kind: MongoDBOpsRequest
metadata:
name: repro
namespace: demo
spec:
type: Reprovision
databaseRef:
name: mongo
apply: Always
spec.type specifies the Type of the ops Requestspec.databaseRef holds the name of the MongoDB database. The db should be available in the same namespace as the opsRequestspec.apply is set to Always to denote that, we want reprovisioning even if the db was not Ready.
Note: The method of reprovisioning the standalone & sharded db is exactly same as above. All you need, is to specify the corresponding MongoDB name in spec.databaseRef.name section.
Let’s create the MongoDBOpsRequest CR we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.3.16/docs/examples/mongodb/reprovision/ops.yaml
mongodbopsrequest.ops.kubedb.com/repro created
Now the Ops-manager operator will
- Pause the DB
- Delete all statefulsets
- Remove
Provisioned condition from db - Reconcile the db for start
- Wait for DB to be Ready.
$ kubectl get mgops -n demo
NAME TYPE STATUS AGE
repro Reprovision Successful 2m
$ kubectl get mgops -n demo -oyaml repro
apiVersion: ops.kubedb.com/v1alpha1
kind: MongoDBOpsRequest
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"ops.kubedb.com/v1alpha1","kind":"MongoDBOpsRequest","metadata":{"annotations":{},"name":"repro","namespace":"demo"},"spec":{"databaseRef":{"name":"mongo"},"type":"Reprovision"}}
creationTimestamp: "2022-10-31T09:50:35Z"
generation: 1
name: repro
namespace: demo
resourceVersion: "743676"
uid: b3444d38-bef3-4043-925f-551fe6c86123
spec:
apply: Always
databaseRef:
name: mongo
type: Reprovision
status:
conditions:
- lastTransitionTime: "2022-10-31T09:50:35Z"
message: MongoDB ops request is reprovisioning the database
observedGeneration: 1
reason: Reprovision
status: "True"
type: Reprovision
- lastTransitionTime: "2022-10-31T09:50:45Z"
message: Successfully Deleted All the StatefulSets
observedGeneration: 1
reason: DeleteStatefulSets
status: "True"
type: DeleteStatefulSets
- lastTransitionTime: "2022-10-31T09:52:05Z"
message: Database Phase is Ready
observedGeneration: 1
reason: DatabaseReady
status: "True"
type: DatabaseReady
- lastTransitionTime: "2022-10-31T09:52:05Z"
message: Successfully Reprovisioned the 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 mongodbopsrequest -n demo repro
kubectl delete mongodb -n demo mongo
kubectl delete ns demo
Next Steps
