Expand volume

You can expand the storage volume size of each pod.

note

Volume expansion triggers a concurrent restart and the pod role may change after the operation.

Before you start

Check whether the cluster STATUS is Running. Otherwise, the following operations may fail.

kbcli

kbcli cluster list mycluster -n demo
>
NAME        NAMESPACE   CLUSTER-DEFINITION   VERSION   TERMINATION-POLICY   STATUS    CREATED-TIME
mycluster   demo        redis                          Delete               Running   Sep 29,2024 09:46 UTC+0800

kubectl

kubectl -n demo get cluster mycluster
>
NAME           CLUSTER-DEFINITION   VERSION        TERMINATION-POLICY   STATUS     AGE
mycluster      redis                               Delete               Running    19m

Steps

kbcli

1. Change configuration.

   Configure the values of --components, --volume-claim-templates, and --storage, and run the command below to expand the volume.

   kbcli cluster volume-expand mycluster -n demo --components="redis" --volume-claim-templates="data" --storage="40Gi"
   • --components describes the component name for volume expansion.
   • --volume-claim-templates describes the VolumeClaimTemplate names in components.
   • --storage describes the volume storage size.

2. Validate the volume expansion operation.

   • View the OpsRequest progress.

     KubeBlocks outputs a command automatically for you to view the details of the OpsRequest progress. The output includes the status of this OpsRequest and PVC. When the status is Succeed, this OpsRequest is completed.

     kbcli cluster describe-ops mycluster-volumeexpansion-ih2r4 -n demo

   • View the cluster status.

     kbcli cluster list mycluster -n demo
     >
     NAME                CLUSTER-DEFINITION        VERSION           TERMINATION-POLICY        STATUS          CREATED-TIME
     redis-cluster        redis                                      Delete                    Updating        Sep 29,2024 09:46 UTC+0800

   • STATUS=Updating: it means the volume expansion is in progress.

   • STATUS=Running: it means the volume expansion operation has been applied.

3. After the OpsRequest status is Succeed or the cluster status is Running again, check whether the corresponding resources change.

   kbcli cluster describe mycluster -n demo

OpsRequest

1. Apply an OpsRequest. Change the value of storage according to your need and run the command below to expand the volume of a cluster.

   kubectl apply -f - <<EOF
   apiVersion: apps.kubeblocks.io/v1alpha1
   kind: OpsRequest
   metadata:
     name: ops-volume-expansion
     namespace: demo
   spec:
     clusterName: mycluster
     type: VolumeExpansion
     volumeExpansion:
     - componentName: redis
       volumeClaimTemplates:
       - name: data
         storage: "40Gi"
   EOF

2. Validate the volume expansion operation.

   kubectl get ops -n demo
   >
   NAMESPACE   NAME                   TYPE              CLUSTER     STATUS    PROGRESS   AGE
   demo        ops-volume-expansion   VolumeExpansion   mycluster   Succeed   3/3        6m

3. Check whether the corresponding cluster resources change.

   kubectl describe cluster mycluster -n demo
   >
   ......
   Volume Claim Templates:
      Name:  data
      Spec:
        Access Modes:
          ReadWriteOnce
        Resources:
          Requests:
            Storage:   40Gi

Edit cluster YAML file

1. Change the value of spec.componentSpecs.volumeClaimTemplates.spec.resources in the cluster YAML file.

   spec.componentSpecs.volumeClaimTemplates.spec.resources is the storage resource information of the pod and changing this value triggers the volume expansion of a cluster.

   spec:
     affinity:
       podAntiAffinity: Preferred
       topologyKeys:
       - kubernetes.io/hostname
     clusterDefinitionRef: redis
     componentSpecs:
     - componentDef: redis
       enabledLogs:
       - running
       disableExporter: true
       name: redis
       replicas: 1
       resources:
         limits:
           cpu: "0.5"
           memory: 0.5Gi
         requests:
           cpu: "0.5"
           memory: 0.5Gi
       serviceAccountName: kb-redis
       volumeClaimTemplates:
       - name: data
         spec:
           accessModes:
           - ReadWriteOnce
           resources:
             requests:
               storage: 40Gi # Change the volume storage size.

2. Check whether the corresponding cluster resources change.

   kubectl describe cluster mycluster -n demo
   >
   ......
   Volume Claim Templates:
      Name:  data
      Spec:
        Access Modes:
          ReadWriteOnce
        Resources:
          Requests:
            Storage:   40Gi