Expand volume

You can expand the storage volume size of each pod.

note

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

Before you start

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

kbcli cluster list <name>

Example

kbcli cluster list pg-cluster
>
NAME              NAMESPACE        CLUSTER-DEFINITION    VERSION                  TERMINATION-POLICY        STATUS         CREATED-TIME
pg-cluster        default          postgresql            postgresql-14.7.0        Delete                    Running        Mar 3,2023 10:29 UTC+0800

Steps

1. Change configuration. There are 3 ways to apply volume expansion.

Option 1. (Recommended) Use kbcli

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

kbcli cluster volume-expand pg-cluster --components="postgresql" \
--volume-claim-templates="data" --storage="2Gi"

• --components describes the component name for volume expansion.
• --volume-claim-templates describes the VolumeClaimTemplate names in components.
• --storage describes the volume storage size.

Option 2. Create an OpsRequest

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
spec:
  clusterRef: pg-cluster
  type: VolumeExpansion
  volumeExpansion:
  - componentName: postgresql
    volumeClaimTemplates:
    - name: data
      storage: "2Gi"
EOF

Option 3. Change the YAML file of the cluster

Change the value of spec.components.volumeClaimTemplates.spec.resources in the cluster YAML file. spec.components.volumeClaimTemplates.spec.resources is the storage resource information of the pod and changing this value triggers the volume expansion of a cluster.

apiVersion: apps.kubeblocks.io/v1alpha1
kind: Cluster
metadata:
  name: pg-cluster
  namespace: default
spec:
  clusterDefinitionRef: postgresql
  clusterVersionRef: postgresql-14.7.0
  componentSpecs:
  - name: postgresql
    componentDefRef: postgresql
    replicas: 1
    volumeClaimTemplates:
    - name: data
      spec:
        accessModes:
          - ReadWriteOnce
        resources:
          requests:
            storage: 1Gi # Change the volume storage size.
  terminationPolicy: Halt

2. Validate the volume expansion.

   kbcli cluster list <name>

   Example

   kbcli cluster list pg-cluster
   >
   NAME              NAMESPACE        CLUSTER-DEFINITION        VERSION                  TERMINATION-POLICY        STATUS                 CREATED-TIME
   pg-cluster        default          postgresql                postgresql-14.7.0        Delete                    VolumeExpanding        Apr 10,2023 16:27 UTC+0800
   • STATUS=VolumeExpanding: it means the volume expansion is in progress.
   • STATUS=Running: it means the volume expansion operation has been applied.