New to KubeDB? Please start here.
Storage Autoscaling of a Ignite Cluster
This guide will show you how to use KubeDB
to autoscale the storage of a Ignite cluster.
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.Install
KubeDB
Community, Enterprise and Autoscaler operator in your cluster following the steps here.Install
Metrics Server
from hereInstall Prometheus from here
You must have a
StorageClass
that supports volume expansion.You should be familiar with the following
KubeDB
concepts:
To keep everything isolated, we are going to use a separate namespace called demo
throughout this tutorial.
$ kubectl create ns demo
namespace/demo created
Storage Autoscaling of Cluster Database
At first verify that your cluster has a storage class, that supports volume expansion. Let’s check,
$ kubectl get storageclass
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
standard (default) rancher.io/local-path Delete WaitForFirstConsumer false 79m
topolvm-provisioner topolvm.cybozu.com Delete WaitForFirstConsumer true 78m
We can see from the output the topolvm-provisioner
storage class has ALLOWVOLUMEEXPANSION
field as true. So, this storage class supports volume expansion. We can use it. You can install topolvm from here
Now, we are going to deploy a Ignite
cluster using a supported version by KubeDB
operator. Then we are going to apply IgniteAutoscaler
to set up autoscaling.
Deploy Ignite Cluster
In this section, we are going to deploy a Ignite cluster with version 2.17.0
. Then, in the next section we will set up autoscaling for this database using IgniteAutoscaler
CRD. Below is the YAML of the Ignite
CR that we are going to create,
If you want to autoscale Ignite
Standalone
, Just remove thespec.Replicas
from the below yaml and rest of the steps are same.
apiVersion: kubedb.com/v1alpha2
kind: Ignite
metadata:
name: ignite-autoscale
namespace: demo
spec:
version: "2.17.0"
replicas: 3
storage:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
storageClassName: topolvm
storageType: Durable
deletionPolicy: WipeOut
podTemplate:
spec:
containers:
- name: ignite
resources:
requests:
cpu: "0.5m"
memory: "1Gi"
limits:
cpu: "1"
memory: "2Gi"
serviceTemplates:
- alias: primary
spec:
type: LoadBalancer
Let’s create the Ignite
CRO we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2025.8.31/docs/guides/ignite/autoscaler/storage/cluster/examples/sample-ignite.yaml
ignite.kubedb.com/ignite-autoscale created
Now, wait until ignite-autoscale
has status Ready
. i.e,
$ kubectl get ignite -n demo
NAME VERSION STATUS AGE
ignite-autoscale 2.17.0 Ready 3m46s
Let’s check volume size from petset, and from the persistent volume,
$ kubectl get petset -n demo ignite-autoscale -o json | jq '.spec.volumeClaimTemplates[].spec.resources.requests.storage'
"1Gi"
$ kubectl get pv -n demo
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-43266d76-f280-4cca-bd78-d13660a84db9 1Gi RWO Delete Bound demo/data-sample-ignite-2 topolvm-provisioner 57s
pvc-4a509b05-774b-42d9-b36d-599c9056af37 1Gi RWO Delete Bound demo/data-sample-ignite-0 topolvm-provisioner 58s
pvc-c27eee12-cd86-4410-b39e-b1dd735fc14d 1Gi RWO Delete Bound demo/data-sample-ignite-1 topolvm-provisioner 57s
You can see the petset has 1GB storage, and the capacity of all the persistent volume is also 1GB.
We are now ready to apply the IgniteAutoscaler
CRO to set up storage autoscaling for this database.
Storage Autoscaling
Here, we are going to set up storage autoscaling using a IgniteAutoscaler Object.
Create IgniteAutoscaler Object
In order to set up vertical autoscaling for this replicaset database, we have to create a IgniteAutoscaler
CRO with our desired configuration. Below is the YAML of the IgniteAutoscaler
object that we are going to create,
apiVersion: autoscaling.kubedb.com/v1alpha1
kind: IgniteAutoscaler
metadata:
name: ignite-storage-autosclaer
namespace: demo
spec:
databaseRef:
name: ignite-autoscale
storage:
ignite:
expansionMode: "Offline"
trigger: "On"
usageThreshold: 20
scalingThreshold: 30
Here,
spec.databaseRef.name
specifies that we are performing vertical scaling operation onignite-autoscale
database.spec.storage.ignite.trigger
specifies that storage autoscaling is enabled for this database.spec.storage.ignite.usageThreshold
specifies storage usage threshold, if storage usage exceeds20%
then storage autoscaling will be triggered.spec.storage.ignite.scalingThreshold
specifies the scaling threshold. Storage will be scaled to20%
of the current amount.spec.storage.ignite.expansionMode
specifies the expansion mode of volume expansionigniteOpsRequest
created byigniteAutoscaler
. topolvm-provisioner supports online volume expansion so hereexpansionMode
is set as “Online”.
Let’s create the igniteAutoscaler
CR we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2025.8.31/docs/guides/ignite/autoscaler/storage/cluster/examples/ig-storage-autoscale-ops.yaml
igniteautoscaler.autoscaling.kubedb.com/ignite-storage-autosclaer created
Storage Autoscaling is set up successfully
Let’s check that the igniteautoscaler
resource is created successfully,
$ kubectl get igniteautoscaler -n demo
NAME AGE
ignite-storage-autosclaer 33s
$ kubectl describe igniteautoscaler ignite-storage-autoscaler -n demo
Name: ignite-storage-autosclaer
Namespace: demo
Labels: <none>
Annotations: API Version: autoscaling.kubedb.com/v1alpha1
Kind: igniteAutoscaler
Metadata:
Creation Timestamp: 2022-01-14T06:08:02Z
Generation: 1
Managed Fields:
...
Resource Version: 24009
UID: 4f45a3b3-fc72-4d04-b52c-a770944311f6
Spec:
Database Ref:
Name: ignite-autoscale
Storage:
ignite:
Scaling Threshold: 20
Trigger: On
Usage Threshold: 20
Events: <none>
So, the igniteautoscaler
resource is created successfully.
Let’s watch the igniteopsrequest
in the demo namespace to see if any igniteopsrequest
object is created. After some time you’ll see that a igniteopsrequest
of type VolumeExpansion
will be created based on the scalingThreshold
.
$ kubectl get igniteopsrequest -n demo
NAME TYPE STATUS AGE
igops-ignite-autoscale-xojkua VolumeExpansion Progressing 15s
Let’s wait for the ops request to become successful.
$ kubectl get igniteopsrequest -n demo
NAME TYPE STATUS AGE
igops-ignite-autoscale-xojkua VolumeExpansion Successful 97s
We can see from the above output that the IgniteOpsRequest
has succeeded. If we describe the IgniteOpsRequest
we will get an overview of the steps that were followed to expand the volume of the database.
$ kubectl describe igniteopsrequest -n demo igops-ignite-autoscale-xojkua
Name: igops-ignite-autoscaleq-xojkua
Namespace: demo
Labels: app.kubernetes.io/component=database
app.kubernetes.io/instance=ignite-autoscale
app.kubernetes.io/managed-by=kubedb.com
app.kubernetes.io/name=ignites.kubedb.com
Annotations: <none>
API Version: ops.kubedb.com/v1alpha1
Kind: igniteOpsRequest
Metadata:
Creation Timestamp: 2022-01-14T06:13:10Z
Generation: 1
Managed Fields: ...
Owner References:
API Version: autoscaling.kubedb.com/v1alpha1
Block Owner Deletion: true
Controller: true
Kind: igniteAutoscaler
Name: ignite-storage-autosclaer
UID: 4f45a3b3-fc72-4d04-b52c-a770944311f6
Resource Version: 25557
UID: 90763a49-a03f-407c-a233-fb20c4ab57d7
Spec:
Database Ref:
Name: ignite-autoscale
Type: VolumeExpansion
Volume Expansion:
ignite: 1594884096
Status:
Conditions:
Last Transition Time: 2022-01-14T06:13:10Z
Message: Controller has started to Progress the igniteOpsRequest: demo/igops-ignite-autoscale-xojkua
Observed Generation: 1
Reason: OpsRequestProgressingStarted
Status: True
Type: Progressing
Last Transition Time: 2022-01-14T06:14:25Z
Message: Volume Expansion performed successfully in ignite pod for igniteOpsRequest: demo/igops-ignite-autoscale-xojkua
Observed Generation: 1
Reason: SuccessfullyVolumeExpanded
Status: True
Type: VolumeExpansion
Last Transition Time: 2022-01-14T06:14:25Z
Message: Controller has successfully expand the volume of ignite demo/igops-ignite-autoscale-xojkua
Observed Generation: 1
Reason: OpsRequestProcessedSuccessfully
Status: True
Type: Successful
Observed Generation: 3
Phase: Successful
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Starting 2m58s KubeDB Enterprise Operator Start processing for igniteOpsRequest: demo/igops-ignite-autoscale-xojkua
Normal Starting 2m58s KubeDB Enterprise Operator Pausing ignite databse: demo/ignite-autoscale
Normal Successful 2m58s KubeDB Enterprise Operator Successfully paused ignite database: demo/ignite-autoscale for igniteOpsRequest: igops-ignite-autoscale-xojkua
Normal Successful 103s KubeDB Enterprise Operator Volume Expansion performed successfully in ignite pod for igniteOpsRequest: demo/igops-ignite-autoscale-xojkua
Normal Starting 103s KubeDB Enterprise Operator Updating ignite storage
Normal Successful 103s KubeDB Enterprise Operator Successfully Updated ignite storage
Normal Starting 103s KubeDB Enterprise Operator Resuming ignite database: demo/ignite-autoscale
Normal Successful 103s KubeDB Enterprise Operator Successfully resumed ignite database: demo/ignite-autoscale
Normal Successful 103s KubeDB Enterprise Operator Controller has Successfully expand the volume of ignite: demo/ignite-autoscale
Now, we are going to verify from the Petset
, and the Persistent Volume
whether the volume of the replicaset database has expanded to meet the desired state, Let’s check,
$ kubectl get petset -n demo ignite-autoscale -o json | jq '.spec.volumeClaimTemplates[].spec.resources.requests.storage'
"1594884096"
$ kubectl get pv -n demo
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-43266d76-f280-4cca-bd78-d13660a84db9 2Gi RWO Delete Bound demo/data-ignite-autoscale-2 topolvm-provisioner 23m
pvc-4a509b05-774b-42d9-b36d-599c9056af37 2Gi RWO Delete Bound demo/data-signite-autoscale-0 topolvm-provisioner 24m
pvc-c27eee12-cd86-4410-b39e-b1dd735fc14d 2Gi RWO Delete Bound demo/data-ignite-autoscale-1 topolvm-provisioner 23m
The above output verifies that we have successfully autoscaled the volume of the ignite cluster.
Cleaning Up
To clean up the Kubernetes resources created by this tutorial, run:
kubectl delete ignite -n demo ignite-autoscale
kubectl delete igniteautoscaler -n demo igops-ignite-autoscale-xojkua
kubectl delete ns demo