New to KubeDB? Please start here.
Storage Autoscaling of a Druid Topology Cluster
This guide will show you how to use KubeDB to autoscale the storage of a Druid Topology cluster.
Before You Begin
At first, you need to have a Kubernetes cluster, and the
kubectlcommand-line tool must be configured to communicate with your cluster.Install
KubeDBProvisioner, Ops-manager and Autoscaler operator in your cluster following the steps here.Install
Metrics Serverfrom hereInstall Prometheus from here
You must have a
StorageClassthat supports volume expansion.You should be familiar with the following
KubeDBconcepts:
To keep everything isolated, we are going to use 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/druid directory of kubedb/docs repository.
Storage Autoscaling of Topology Cluster
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
local-path (default) rancher.io/local-path Delete WaitForFirstConsumer false 28h
longhorn (default) driver.longhorn.io Delete Immediate true 28h
longhorn-static driver.longhorn.io Delete Immediate true 28h
We can see from the output the longhorn storage class has ALLOWVOLUMEEXPANSION field as true. So, this storage class supports volume expansion. We can use it.
Now, we are going to deploy a Druid topology using a supported version by KubeDB operator. Then we are going to apply DruidAutoscaler to set up autoscaling.
Create External Dependency (Deep Storage)
Before proceeding further, we need to prepare deep storage, which is one of the external dependency of Druid and used for storing the segments. It is a storage mechanism that Apache Druid does not provide. Amazon S3, Google Cloud Storage, or Azure Blob Storage, S3-compatible storage (like Minio), or HDFS are generally convenient options for deep storage.
In this tutorial, we will run a minio-server as deep storage in our local kind cluster using minio-operator and create a bucket named druid in it, which the deployed druid database will use.
$ helm repo add minio https://operator.min.io/
$ helm repo update minio
$ helm upgrade --install --namespace "minio-operator" --create-namespace "minio-operator" minio/operator --set operator.replicaCount=1
$ helm upgrade --install --namespace "demo" --create-namespace druid-minio minio/tenant \
--set tenant.pools[0].servers=1 \
--set tenant.pools[0].volumesPerServer=1 \
--set tenant.pools[0].size=1Gi \
--set tenant.certificate.requestAutoCert=false \
--set tenant.buckets[0].name="druid" \
--set tenant.pools[0].name="default"
Now we need to create a Secret named deep-storage-config. It contains the necessary connection information using which the druid database will connect to the deep storage.
apiVersion: v1
kind: Secret
metadata:
name: deep-storage-config
namespace: demo
stringData:
druid.storage.type: "s3"
druid.storage.bucket: "druid"
druid.storage.baseKey: "druid/segments"
druid.s3.accessKey: "minio"
druid.s3.secretKey: "minio123"
druid.s3.protocol: "http"
druid.s3.enablePathStyleAccess: "true"
druid.s3.endpoint.signingRegion: "us-east-1"
druid.s3.endpoint.url: "http://myminio-hl.demo.svc.cluster.local:9000/"
Let’s create the deep-storage-config Secret shown above:
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/druid/autoscaler/storage/yamls/deep-storage-config.yaml
secret/deep-storage-config created
Deploy Druid Cluster
In this section, we are going to deploy a Druid topology cluster with monitoring enabled and with version 28.0.1. Then, in the next section we will set up autoscaling for this cluster using DruidAutoscaler CRD. Below is the YAML of the Druid CR that we are going to create,
apiVersion: kubedb.com/v1alpha2
kind: Druid
metadata:
name: druid-cluster
namespace: demo
spec:
version: 28.0.1
deepStorage:
type: s3
configSecret:
name: deep-storage-config
topology:
historicals:
replicas: 1
storage:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
storageType: Durable
middleManagers:
replicas: 1
storage:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
storageType: Durable
routers:
replicas: 1
deletionPolicy: Delete
monitor:
agent: prometheus.io/operator
prometheus:
serviceMonitor:
labels:
release: prometheus
interval: 10s
Let’s create the Druid CRO we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/druid/autoscaler/storage/yamls/druid-cluster.yaml
druid.kubedb.com/druid-cluster created
Now, wait until druid-cluster has status Ready. i.e,
$ kubectl get dr -n demo -w
NAME TYPE VERSION STATUS AGE
druid-cluster kubedb.com/v1alpha2 28.0.1 Provisioning 0s
druid-cluster kubedb.com/v1alpha2 28.0.1 Provisioning 24s
.
.
druid-cluster kubedb.com/v1alpha2 28.0.1 Ready 2m20s
Let’s check volume size from petset, and from the persistent volume,
$ kubectl get petset -n demo druid-cluster-historicals -o json | jq '.spec.volumeClaimTemplates[].spec.resources.requests.storage'
"1Gi"
$ kubectl get petset -n demo druid-cluster-middleManagers -o json | jq '.spec.volumeClaimTemplates[].spec.resources.requests.storage'
"1Gi"
$ kubectl get pv -n demo
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS VOLUMEATTRIBUTESCLASS REASON AGE
pvc-2c0ef2aa-0438-4d75-9cb2-c12a176bae6a 1Gi RWO Delete Bound demo/druid-cluster-base-task-dir-druid-cluster-middlemanagers-0 longhorn <unset> 95s
pvc-5f4cea5f-e0c8-4339-b67c-9cb8b02ba49d 1Gi RWO Delete Bound demo/druid-cluster-segment-cache-druid-cluster-historicals-0 longhorn <unset> 96s
You can see the petset for both historicals and middleManagers has 1GB storage, and the capacity of all the persistent volume is also 1GB.
We are now ready to apply the DruidAutoscaler CRO to set up storage autoscaling for this cluster(historicals and middleManagers).
Storage Autoscaling
Here, we are going to set up storage autoscaling using a DruidAutoscaler Object.
Create DruidAutoscaler Object
In order to set up vertical autoscaling for this topology cluster, we have to create a DruidAutoscaler CRO with our desired configuration. Below is the YAML of the DruidAutoscaler object that we are going to create,
apiVersion: autoscaling.kubedb.com/v1alpha1
kind: DruidAutoscaler
metadata:
name: druid-storage-autoscaler
namespace: demo
spec:
databaseRef:
name: druid-cluster
storage:
historicals:
expansionMode: "Offline"
trigger: "On"
usageThreshold: 60
scalingThreshold: 100
middleManagers:
expansionMode: "Offline"
trigger: "On"
usageThreshold: 60
scalingThreshold: 100
Here,
spec.clusterRef.namespecifies that we are performing vertical scaling operation ondruid-clustercluster.spec.storage.historicals.trigger/spec.storage.middleManagers.triggerspecifies that storage autoscaling is enabled for historicals and middleManagers of topology cluster.spec.storage.historicals.usageThreshold/spec.storage.middleManagers.usageThresholdspecifies storage usage threshold, if storage usage exceeds60%then storage autoscaling will be triggered.spec.storage.historicals.scalingThreshold/spec.storage.historicals.scalingThresholdspecifies the scaling threshold. Storage will be scaled to100%of the current amount.- It has another field
spec.storage.historicals.expansionMode/spec.storage.middleManagers.expansionModeto set the opsRequest volumeExpansionMode, which support two values:Online&Offline. Default value isOnline.
Let’s create the DruidAutoscaler CR we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.11.18/docs/guides/druid/autoscaler/storage/yamls/druid-storage-autoscaler.yaml
druidautoscaler.autoscaling.kubedb.com/druid-storage-autoscaler created
Storage Autoscaling is set up successfully
Let’s check that the druidautoscaler resource is created successfully,
$ kubectl get druidautoscaler -n demo
NAME AGE
druid-storage-autoscaler 34s
$ kubectl describe druidautoscaler -n demo druid-storage-autoscaler
Name: druid-storage-autoscaler
Namespace: demo
Labels: <none>
Annotations: <none>
API Version: autoscaling.kubedb.com/v1alpha1
Kind: DruidAutoscaler
Metadata:
Creation Timestamp: 2024-10-25T09:52:37Z
Generation: 1
Managed Fields:
API Version: autoscaling.kubedb.com/v1alpha1
Fields Type: FieldsV1
fieldsV1:
f:metadata:
f:annotations:
.:
f:kubectl.kubernetes.io/last-applied-configuration:
f:spec:
.:
f:databaseRef:
f:storage:
.:
f:historicals:
.:
f:expansionMode:
f:scalingThreshold:
f:trigger:
f:usageThreshold:
f:middleManagers:
.:
f:expansionMode:
f:scalingThreshold:
f:trigger:
f:usageThreshold:
Manager: kubectl-client-side-apply
Operation: Update
Time: 2024-10-25T09:52:37Z
API Version: autoscaling.kubedb.com/v1alpha1
Fields Type: FieldsV1
fieldsV1:
f:metadata:
f:ownerReferences:
.:
k:{"uid":"712730e8-41ef-4700-b184-825b30ecbc8c"}:
Manager: kubedb-autoscaler
Operation: Update
Time: 2024-10-25T09:52:37Z
Owner References:
API Version: kubedb.com/v1alpha2
Block Owner Deletion: true
Controller: true
Kind: Druid
Name: druid-cluster
UID: 712730e8-41ef-4700-b184-825b30ecbc8c
Resource Version: 226662
UID: 57cbd906-a9b7-4649-bfe0-304840bb60c1
Spec:
Database Ref:
Name: druid-cluster
Ops Request Options:
Apply: IfReady
Storage:
Historicals:
Expansion Mode: Offline
Scaling Rules:
Applies Upto:
Threshold: 100pc
Scaling Threshold: 100
Trigger: On
Usage Threshold: 60
Middle Managers:
Expansion Mode: Offline
Scaling Rules:
Applies Upto:
Threshold: 100pc
Scaling Threshold: 100
Trigger: On
Usage Threshold: 60
Events: <none>
So, the druidautoscaler resource is created successfully.
Now, for this demo, we are going to manually fill up the persistent volume to exceed the usageThreshold using dd command to see if storage autoscaling is working or not.
We are autoscaling volume for both historicals and middleManagers. So we need to fill up the persistent volume for both historicals and middleManagers.
- Lets exec into the historicals pod and fill the cluster volume using the following commands:
$ kubectl exec -it -n demo druid-cluster-historicals-0 -- bash
bash-5.1$ df -h /druid/data/segments
Filesystem Size Used Available Use% Mounted on
/dev/longhorn/pvc-d4ef15ef-b1af-4a1f-ad25-ad9bc990a2fb 973.4M 92.0K 957.3M 0% /druid/data/segment
bash-5.1$ dd if=/dev/zero of=/druid/data/segments/file.img bs=600M count=1
1+0 records in
1+0 records out
629145600 bytes (600.0MB) copied, 46.709228 seconds, 12.8MB/s
bash-5.1$ df -h /druid/data/segments
Filesystem Size Used Available Use% Mounted on
/dev/longhorn/pvc-d4ef15ef-b1af-4a1f-ad25-ad9bc990a2fb 973.4M 600.1M 357.3M 63% /druid/data/segments
- Let’s exec into the middleManagers pod and fill the cluster volume using the following commands:
$ kubectl exec -it -n demo druid-cluster-middleManagers-0 -- bash
druid@druid-cluster-middleManagers-0:~$ df -h /var/druid/task
Filesystem Size Used Available Use% Mounted on
/dev/longhorn/pvc-2c0ef2aa-0438-4d75-9cb2-c12a176bae6a 973.4M 24.0K 957.4M 0% /var/druid/task
druid@druid-cluster-middleManagers-0:~$ dd if=/dev/zero of=/var/druid/task/file.img bs=600M count=1
1+0 records in
1+0 records out
629145600 bytes (629 MB, 600 MiB) copied, 3.39618 s, 185 MB/s
druid@druid-cluster-middleManagers-0:~$ df -h /var/druid/task
Filesystem Size Used Available Use% Mounted on
/dev/longhorn/pvc-2c0ef2aa-0438-4d75-9cb2-c12a176bae6a 973.4M 600.0M 357.4M 63% /var/druid/task
So, from the above output we can see that the storage usage is 63% for both nodes, which exceeded the usageThreshold 60%.
There will be two DruidOpsRequest created for both historicals and middleManagers to expand the volume of the cluster for both nodes.
Let’s watch the druidopsrequest in the demo namespace to see if any druidopsrequest object is created. After some time you’ll see that a druidopsrequest of type VolumeExpansion will be created based on the scalingThreshold.
$ watch kubectl get druidopsrequest -n demo
NAME TYPE STATUS AGE
druidopsrequest.ops.kubedb.com/drops-druid-cluster-gq9huj VolumeExpansion Progressing 46s
druidopsrequest.ops.kubedb.com/drops-druid-cluster-kbw4fd VolumeExpansion Successful 4m46s
Once ops request has succeeded. Let’s wait for the other one to become successful.
$ kubectl get druidopsrequest -n demo
NAME TYPE STATUS AGE
druidopsrequest.ops.kubedb.com/drops-druid-cluster-gq9huj VolumeExpansion Successful 3m18s
druidopsrequest.ops.kubedb.com/drops-druid-cluster-kbw4fd VolumeExpansion Successful 7m18s
We can see from the above output that the both DruidOpsRequest has succeeded. If we describe the DruidOpsRequest one by one we will get an overview of the steps that were followed to expand the volume of the cluster.
$ kubectl describe druidopsrequest -n demo drops-druid-cluster-kbw4fd
Name: drops-druid-cluster-kbw4fd
Namespace: demo
Labels: app.kubernetes.io/component=database
app.kubernetes.io/instance=druid-cluster
app.kubernetes.io/managed-by=kubedb.com
app.kubernetes.io/name=druids.kubedb.com
Annotations: <none>
API Version: ops.kubedb.com/v1alpha1
Kind: DruidOpsRequest
Metadata:
Creation Timestamp: 2024-10-25T09:57:14Z
Generation: 1
Managed Fields:
API Version: ops.kubedb.com/v1alpha1
Fields Type: FieldsV1
fieldsV1:
f:metadata:
f:labels:
.:
f:app.kubernetes.io/component:
f:app.kubernetes.io/instance:
f:app.kubernetes.io/managed-by:
f:app.kubernetes.io/name:
f:ownerReferences:
.:
k:{"uid":"57cbd906-a9b7-4649-bfe0-304840bb60c1"}:
f:spec:
.:
f:apply:
f:databaseRef:
f:type:
f:volumeExpansion:
.:
f:historicals:
f:mode:
Manager: kubedb-autoscaler
Operation: Update
Time: 2024-10-25T09:57:14Z
API Version: ops.kubedb.com/v1alpha1
Fields Type: FieldsV1
fieldsV1:
f:status:
.:
f:conditions:
f:observedGeneration:
f:phase:
Manager: kubedb-ops-manager
Operation: Update
Subresource: status
Time: 2024-10-25T10:00:20Z
Owner References:
API Version: autoscaling.kubedb.com/v1alpha1
Block Owner Deletion: true
Controller: true
Kind: DruidAutoscaler
Name: druid-storage-autoscaler
UID: 57cbd906-a9b7-4649-bfe0-304840bb60c1
Resource Version: 228016
UID: 1fa750bb-2db3-4684-a7cf-1b3047bc07af
Spec:
Apply: IfReady
Database Ref:
Name: druid-cluster
Type: VolumeExpansion
Volume Expansion:
Historicals: 2041405440
Mode: Offline
Status:
Conditions:
Last Transition Time: 2024-10-25T09:57:14Z
Message: Druid ops-request has started to expand volume of druid nodes.
Observed Generation: 1
Reason: VolumeExpansion
Status: True
Type: VolumeExpansion
Last Transition Time: 2024-10-25T09:57:22Z
Message: get pet set; ConditionStatus:True
Observed Generation: 1
Status: True
Type: GetPetSet
Last Transition Time: 2024-10-25T09:57:22Z
Message: is pet set deleted; ConditionStatus:True
Observed Generation: 1
Status: True
Type: IsPetSetDeleted
Last Transition Time: 2024-10-25T09:57:32Z
Message: successfully deleted the petSets with orphan propagation policy
Observed Generation: 1
Reason: OrphanPetSetPods
Status: True
Type: OrphanPetSetPods
Last Transition Time: 2024-10-25T09:57:37Z
Message: get pod; ConditionStatus:True
Observed Generation: 1
Status: True
Type: GetPod
Last Transition Time: 2024-10-25T09:57:37Z
Message: is ops req patched; ConditionStatus:True
Observed Generation: 1
Status: True
Type: IsOpsReqPatched
Last Transition Time: 2024-10-25T09:57:37Z
Message: create pod; ConditionStatus:True
Observed Generation: 1
Status: True
Type: CreatePod
Last Transition Time: 2024-10-25T09:57:42Z
Message: get pvc; ConditionStatus:True
Observed Generation: 1
Status: True
Type: GetPvc
Last Transition Time: 2024-10-25T09:57:42Z
Message: is pvc patched; ConditionStatus:True
Observed Generation: 1
Status: True
Type: IsPvcPatched
Last Transition Time: 2024-10-25T09:59:27Z
Message: compare storage; ConditionStatus:True
Observed Generation: 1
Status: True
Type: CompareStorage
Last Transition Time: 2024-10-25T09:59:27Z
Message: create; ConditionStatus:True
Observed Generation: 1
Status: True
Type: Create
Last Transition Time: 2024-10-25T09:59:35Z
Message: is druid running; ConditionStatus:False
Observed Generation: 1
Status: False
Type: IsDruidRunning
Last Transition Time: 2024-10-25T09:59:57Z
Message: successfully updated historicals node PVC sizes
Observed Generation: 1
Reason: UpdateHistoricalsNodePVCs
Status: True
Type: UpdateHistoricalsNodePVCs
Last Transition Time: 2024-10-25T10:00:15Z
Message: successfully reconciled the Druid resources
Observed Generation: 1
Reason: UpdatePetSets
Status: True
Type: UpdatePetSets
Last Transition Time: 2024-10-25T10:00:20Z
Message: PetSet is recreated
Observed Generation: 1
Reason: ReadyPetSets
Status: True
Type: ReadyPetSets
Last Transition Time: 2024-10-25T10:00:20Z
Message: Successfully completed volumeExpansion for Druid
Observed Generation: 1
Reason: Successful
Status: True
Type: Successful
Observed Generation: 1
Phase: Successful
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Starting 8m29s KubeDB Ops-manager Operator Start processing for DruidOpsRequest: demo/drops-druid-cluster-kbw4fd
Normal Starting 8m29s KubeDB Ops-manager Operator Pausing Druid databse: demo/druid-cluster
Normal Successful 8m29s KubeDB Ops-manager Operator Successfully paused Druid database: demo/druid-cluster for DruidOpsRequest: drops-druid-cluster-kbw4fd
Warning get pet set; ConditionStatus:True 8m21s KubeDB Ops-manager Operator get pet set; ConditionStatus:True
Warning is pet set deleted; ConditionStatus:True 8m21s KubeDB Ops-manager Operator is pet set deleted; ConditionStatus:True
Warning get pet set; ConditionStatus:True 8m16s KubeDB Ops-manager Operator get pet set; ConditionStatus:True
Normal OrphanPetSetPods 8m11s KubeDB Ops-manager Operator successfully deleted the petSets with orphan propagation policy
Warning get pod; ConditionStatus:True 8m6s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning is ops req patched; ConditionStatus:True 8m6s KubeDB Ops-manager Operator is ops req patched; ConditionStatus:True
Warning create pod; ConditionStatus:True 8m6s KubeDB Ops-manager Operator create pod; ConditionStatus:True
Warning get pod; ConditionStatus:True 8m1s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 8m1s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning is pvc patched; ConditionStatus:True 8m1s KubeDB Ops-manager Operator is pvc patched; ConditionStatus:True
Warning compare storage; ConditionStatus:False 8m1s KubeDB Ops-manager Operator compare storage; ConditionStatus:False
Warning get pod; ConditionStatus:True 7m56s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m56s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m51s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m51s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m46s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m46s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m41s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m41s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m36s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m36s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m31s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m31s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m26s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m26s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m21s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m21s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m16s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m16s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m11s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m11s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m6s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m6s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 7m1s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 7m1s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m56s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m56s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m51s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m51s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m46s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m46s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m41s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m41s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m36s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m36s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m31s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m31s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m26s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m26s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m21s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m21s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m16s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 6m16s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning compare storage; ConditionStatus:True 6m16s KubeDB Ops-manager Operator compare storage; ConditionStatus:True
Warning create; ConditionStatus:True 6m16s KubeDB Ops-manager Operator create; ConditionStatus:True
Warning is ops req patched; ConditionStatus:True 6m16s KubeDB Ops-manager Operator is ops req patched; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m11s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning is druid running; ConditionStatus:False 6m8s KubeDB Ops-manager Operator is druid running; ConditionStatus:False
Warning get pod; ConditionStatus:True 6m6s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pod; ConditionStatus:True 6m1s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pod; ConditionStatus:True 5m56s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pod; ConditionStatus:True 5m51s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Normal UpdateHistoricalsNodePVCs 5m46s KubeDB Ops-manager Operator successfully updated historicals node PVC sizes
Normal UpdatePetSets 5m28s KubeDB Ops-manager Operator successfully reconciled the Druid resources
Warning get pet set; ConditionStatus:True 5m23s KubeDB Ops-manager Operator get pet set; ConditionStatus:True
Normal ReadyPetSets 5m23s KubeDB Ops-manager Operator PetSet is recreated
Normal Starting 5m23s KubeDB Ops-manager Operator Resuming Druid database: demo/druid-cluster
Normal Successful 5m23s KubeDB Ops-manager Operator Successfully resumed Druid database: demo/druid-cluster for DruidOpsRequest: drops-druid-cluster-kbw4fd
Normal UpdatePetSets 5m18s KubeDB Ops-manager Operator successfully reconciled the Druid resources
Normal UpdatePetSets 5m8s KubeDB Ops-manager Operator successfully reconciled the Druid resources
Normal UpdatePetSets 4m57s KubeDB Ops-manager Operator successfully reconciled the Druid resources
$ kubectl describe druidopsrequest -n demo drops-druid-cluster-gq9huj
Name: drops-druid-cluster-gq9huj
Namespace: demo
Labels: app.kubernetes.io/component=database
app.kubernetes.io/instance=druid-cluster
app.kubernetes.io/managed-by=kubedb.com
app.kubernetes.io/name=druids.kubedb.com
Annotations: <none>
API Version: ops.kubedb.com/v1alpha1
Kind: DruidOpsRequest
Metadata:
Creation Timestamp: 2024-10-25T10:01:14Z
Generation: 1
Managed Fields:
API Version: ops.kubedb.com/v1alpha1
Fields Type: FieldsV1
fieldsV1:
f:metadata:
f:labels:
.:
f:app.kubernetes.io/component:
f:app.kubernetes.io/instance:
f:app.kubernetes.io/managed-by:
f:app.kubernetes.io/name:
f:ownerReferences:
.:
k:{"uid":"57cbd906-a9b7-4649-bfe0-304840bb60c1"}:
f:spec:
.:
f:apply:
f:databaseRef:
f:type:
f:volumeExpansion:
.:
f:middleManagers:
f:mode:
Manager: kubedb-autoscaler
Operation: Update
Time: 2024-10-25T10:01:14Z
API Version: ops.kubedb.com/v1alpha1
Fields Type: FieldsV1
fieldsV1:
f:status:
.:
f:conditions:
f:observedGeneration:
f:phase:
Manager: kubedb-ops-manager
Operation: Update
Subresource: status
Time: 2024-10-25T10:04:12Z
Owner References:
API Version: autoscaling.kubedb.com/v1alpha1
Block Owner Deletion: true
Controller: true
Kind: DruidAutoscaler
Name: druid-storage-autoscaler
UID: 57cbd906-a9b7-4649-bfe0-304840bb60c1
Resource Version: 228783
UID: 3b97380c-e867-467f-b366-4b50c7cd7d6d
Spec:
Apply: IfReady
Database Ref:
Name: druid-cluster
Type: VolumeExpansion
Volume Expansion:
Middle Managers: 2041405440
Mode: Offline
Status:
Conditions:
Last Transition Time: 2024-10-25T10:01:14Z
Message: Druid ops-request has started to expand volume of druid nodes.
Observed Generation: 1
Reason: VolumeExpansion
Status: True
Type: VolumeExpansion
Last Transition Time: 2024-10-25T10:01:22Z
Message: get pet set; ConditionStatus:True
Observed Generation: 1
Status: True
Type: GetPetSet
Last Transition Time: 2024-10-25T10:01:22Z
Message: is pet set deleted; ConditionStatus:True
Observed Generation: 1
Status: True
Type: IsPetSetDeleted
Last Transition Time: 2024-10-25T10:01:32Z
Message: successfully deleted the petSets with orphan propagation policy
Observed Generation: 1
Reason: OrphanPetSetPods
Status: True
Type: OrphanPetSetPods
Last Transition Time: 2024-10-25T10:01:37Z
Message: get pod; ConditionStatus:True
Observed Generation: 1
Status: True
Type: GetPod
Last Transition Time: 2024-10-25T10:01:37Z
Message: is ops req patched; ConditionStatus:True
Observed Generation: 1
Status: True
Type: IsOpsReqPatched
Last Transition Time: 2024-10-25T10:01:37Z
Message: create pod; ConditionStatus:True
Observed Generation: 1
Status: True
Type: CreatePod
Last Transition Time: 2024-10-25T10:01:42Z
Message: get pvc; ConditionStatus:True
Observed Generation: 1
Status: True
Type: GetPvc
Last Transition Time: 2024-10-25T10:01:42Z
Message: is pvc patched; ConditionStatus:True
Observed Generation: 1
Status: True
Type: IsPvcPatched
Last Transition Time: 2024-10-25T10:03:32Z
Message: compare storage; ConditionStatus:True
Observed Generation: 1
Status: True
Type: CompareStorage
Last Transition Time: 2024-10-25T10:03:32Z
Message: create; ConditionStatus:True
Observed Generation: 1
Status: True
Type: Create
Last Transition Time: 2024-10-25T10:03:40Z
Message: is druid running; ConditionStatus:False
Observed Generation: 1
Status: False
Type: IsDruidRunning
Last Transition Time: 2024-10-25T10:03:52Z
Message: successfully updated middleManagers node PVC sizes
Observed Generation: 1
Reason: UpdateMiddleManagersNodePVCs
Status: True
Type: UpdateMiddleManagersNodePVCs
Last Transition Time: 2024-10-25T10:04:07Z
Message: successfully reconciled the Druid resources
Observed Generation: 1
Reason: UpdatePetSets
Status: True
Type: UpdatePetSets
Last Transition Time: 2024-10-25T10:04:12Z
Message: PetSet is recreated
Observed Generation: 1
Reason: ReadyPetSets
Status: True
Type: ReadyPetSets
Last Transition Time: 2024-10-25T10:04:12Z
Message: Successfully completed volumeExpansion for Druid
Observed Generation: 1
Reason: Successful
Status: True
Type: Successful
Observed Generation: 1
Phase: Successful
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Starting 5m33s KubeDB Ops-manager Operator Start processing for DruidOpsRequest: demo/drops-druid-cluster-gq9huj
Normal Starting 5m33s KubeDB Ops-manager Operator Pausing Druid databse: demo/druid-cluster
Normal Successful 5m33s KubeDB Ops-manager Operator Successfully paused Druid database: demo/druid-cluster for DruidOpsRequest: drops-druid-cluster-gq9huj
Warning get pet set; ConditionStatus:True 5m25s KubeDB Ops-manager Operator get pet set; ConditionStatus:True
Warning is pet set deleted; ConditionStatus:True 5m25s KubeDB Ops-manager Operator is pet set deleted; ConditionStatus:True
Warning get pet set; ConditionStatus:True 5m20s KubeDB Ops-manager Operator get pet set; ConditionStatus:True
Normal OrphanPetSetPods 5m15s KubeDB Ops-manager Operator successfully deleted the petSets with orphan propagation policy
Warning get pod; ConditionStatus:True 5m10s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning is ops req patched; ConditionStatus:True 5m10s KubeDB Ops-manager Operator is ops req patched; ConditionStatus:True
Warning create pod; ConditionStatus:True 5m10s KubeDB Ops-manager Operator create pod; ConditionStatus:True
Warning get pod; ConditionStatus:True 5m5s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 5m5s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning is pvc patched; ConditionStatus:True 5m5s KubeDB Ops-manager Operator is pvc patched; ConditionStatus:True
Warning compare storage; ConditionStatus:False 5m5s KubeDB Ops-manager Operator compare storage; ConditionStatus:False
Warning get pod; ConditionStatus:True 5m KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 5m KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m55s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m55s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m50s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m50s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m45s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m45s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m40s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m40s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m35s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m35s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m30s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m30s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m25s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m25s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m20s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m20s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m15s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m15s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m10s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m10s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m5s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m5s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 4m KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 4m KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m55s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m55s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m50s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m50s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m45s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m45s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m40s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m40s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m35s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m35s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m30s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m30s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m25s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m25s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m20s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m20s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m15s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pvc; ConditionStatus:True 3m15s KubeDB Ops-manager Operator get pvc; ConditionStatus:True
Warning compare storage; ConditionStatus:True 3m15s KubeDB Ops-manager Operator compare storage; ConditionStatus:True
Warning create; ConditionStatus:True 3m15s KubeDB Ops-manager Operator create; ConditionStatus:True
Warning is ops req patched; ConditionStatus:True 3m15s KubeDB Ops-manager Operator is ops req patched; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m10s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning is druid running; ConditionStatus:False 3m7s KubeDB Ops-manager Operator is druid running; ConditionStatus:False
Warning get pod; ConditionStatus:True 3m5s KubeDB Ops-manager Operator get pod; ConditionStatus:True
Warning get pod; ConditionStatus:True 3m KubeDB Ops-manager Operator get pod; ConditionStatus:True
Normal UpdateMiddleManagersNodePVCs 2m55s KubeDB Ops-manager Operator successfully updated middleManagers node PVC sizes
Normal UpdatePetSets 2m40s KubeDB Ops-manager Operator successfully reconciled the Druid resources
Warning get pet set; ConditionStatus:True 2m35s KubeDB Ops-manager Operator get pet set; ConditionStatus:True
Normal ReadyPetSets 2m35s KubeDB Ops-manager Operator PetSet is recreated
Normal Starting 2m35s KubeDB Ops-manager Operator Resuming Druid database: demo/druid-cluster
Normal Successful 2m35s KubeDB Ops-manager Operator Successfully resumed Druid database: demo/druid-cluster for DruidOpsRequest: drops-druid-cluster-gq9huj
Now, we are going to verify from the Petset, and the Persistent Volume whether the volume of the topology cluster has expanded to meet the desired state, Let’s check,
$ kubectl get petset -n demo druid-cluster-historicals -o json | jq '.spec.volumeClaimTemplates[].spec.resources.requests.storage'
"2041405440"
$ kubectl get petset -n demo druid-cluster-middleManagers -o json | jq '.spec.volumeClaimTemplates[].spec.resources.requests.storage'
"2041405440"
$ kubectl get pv -n demo
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS VOLUMEATTRIBUTESCLASS REASON AGE
pvc-2c0ef2aa-0438-4d75-9cb2-c12a176bae6a 1948Mi RWO Delete Bound demo/druid-cluster-base-task-dir-druid-cluster-middlemanagers-0 longhorn <unset> 19m
pvc-5f4cea5f-e0c8-4339-b67c-9cb8b02ba49d 1948Mi RWO Delete Bound demo/druid-cluster-segment-cache-druid-cluster-historicals-0 longhorn <unset> 19m
The above output verifies that we have successfully autoscaled the volume of the Druid topology cluster for both historicals and middleManagers.
Cleaning Up
To clean up the Kubernetes resources created by this tutorial, run:
kubectl delete druidopsrequests -n demo drops-druid-cluster-gq9huj drops-druid-cluster-kbw4fd
kubectl delete druidutoscaler -n demo druid-storage-autoscaler
kubectl delete dr -n demo druid-cluster
Next Steps
- Detail concepts of Druid object.
- Different Druid topology clustering modes here.
- Monitor your Druid database with KubeDB using out-of-the-box Prometheus operator.
- Want to hack on KubeDB? Check our contribution guidelines.