External etcd

Limited vCluster Tenancy Configuration Support

This feature is only available for the following:

Running the control plane as a container and the following worker node types:

• Host Nodes
• Private Nodes

When using this backing store option, etcd is deployed on the host cluster in the same namespace as the vClustervClusterAn open-source software product that creates and manages virtual Kubernetes clusters inside a host Kubernetes cluster. vCluster improves isolation and multi-tenancy capabilities while reducing infrastructure costs.Related: Virtual Cluster, Host Cluster control plane pod. vCluster deploys etcd with a StatefulSet, Service, and headless Service.

controlPlane:
  backingStore:
    etcd:
      deploy:
        enabled: true

Customize the resources

You can customize the resources that is deployed for etcd. Here are some basic examples, but more options exist in the configuration.

Set resource requests for the StatefulSet

controlPlane:
  backingStore:
    etcd:
      deploy:
        enabled: true
        statefulSet:
          resources:
            requests:
              cpu: 20m
              memory: 150Mi

Add annotations to each etcd component

controlPlane:
  backingStore:
    etcd:
      deploy:
        enabled: true
        statefulSet:
          annotations:
            app.kubernetes.io/part-of: "etcd"
            cluster-autoscaler.kubernetes.io/safe-to-evict: "false"
        service:
          annotations:
            app.kubernetes.io/part-of: "etcd"
        headlessService:
          annotations:
            app.kubernetes.io/part-of: "etcd"

Set the security context of the StatefulSet

controlPlane:
  backingStore:
    etcd:
      deploy:
        enabled: true
        statefulSet:
          security:
            podSecurityContext:
              allowPrivilegeEscalation: false

Migration options

Migrate to embedded etcd

Enterprise-Only Feature

This feature is an Enterprise feature. See our pricing plans or contact our sales team for more information.

You can migrate from deployed etcdetcdA distributed key-value store that provides reliable storage for Kubernetes cluster data. In vCluster, etcd can be deployed externally or embedded within the vCluster pod.Related: Control Plane to embedded etcd without data loss. This migration simplifies your deployment and reduces resource consumption.

Migration guide available

For step-by-step instructions on migrating from deployed to embedded etcd while preserving all your data, see the complete migration guide.

vcluster.yaml

controlPlane:
  backingStore:
    etcd:
      embedded:
        enabled: true
        migrateFromDeployedEtcd: true

Deploying with migrateFromDeployedEtcd: true retains the external etcd StatefulSet to perform the migration. After a successful migration, you should see the Successfully migrated etcd database to embedded etcd log message in vCluster. To remove the external etcd after migration, delete migrateFromDeployedEtcd: true from the vcluster.yaml:

vcluster.yaml after etcd migration

controlPlane:
  backingStore:
    etcd:
      embedded:
        enabled: true

Config reference

deploy required object

Deploy defines to use an external etcd that is deployed by the helm chart

enabled required boolean false

Enabled defines that an external etcd should be deployed.

statefulSet required object

StatefulSet holds options for the external etcd statefulSet.

enabled required boolean true

Enabled defines if the statefulSet should be deployed

enableServiceLinks required boolean true

EnableServiceLinks for the StatefulSet pod

image required object

Image is the image to use for the external etcd statefulSet

registry required string registry.k8s.io

Registry is the registry of the container image, e.g. my-registry.com or ghcr.io. This setting can be globally overridden via the controlPlane.advanced.defaultImageRegistry option. Empty means docker hub.

repository required string etcd

Repository is the repository of the container image, e.g. my-repo/my-image

tag required string 3.6.4-0

Tag is the tag of the container image, and is the default version.

imagePullPolicy required string

ImagePullPolicy is the pull policy for the external etcd image

env required object[] []

Env are extra environment variables

extraArgs required string[] []

ExtraArgs are appended to the etcd command.

resources required object

Resources the etcd can consume

limits required object

Limits are resource limits for the container

requests required object map[cpu:20m memory:150Mi]

Requests are minimal resources that will be consumed by the container

pods required object

Pods defines extra metadata for the etcd pods.

annotations required object {}

Annotations are extra annotations for this resource.

labels required object {}

Labels are extra labels for this resource.

highAvailability required object

HighAvailability are high availability options

replicas required integer 1

Replicas are the amount of pods to use.

scheduling required object

Scheduling options for the etcd pods.

nodeSelector required object {}

NodeSelector is the node selector to apply to the pod.

affinity required object {}

Affinity is the affinity to apply to the pod.

tolerations required object[] []

Tolerations are the tolerations to apply to the pod.

priorityClassName required string

PriorityClassName is the priority class name for the the pod.

podManagementPolicy required string Parallel

PodManagementPolicy is the statefulSet pod management policy.

topologySpreadConstraints required object[] []

TopologySpreadConstraints are the topology spread constraints for the pod.

security required object

Security options for the etcd pods.

podSecurityContext required object {}

PodSecurityContext specifies security context options on the pod level.

containerSecurityContext required object {}

ContainerSecurityContext specifies security context options on the container level.

persistence required object

Persistence options for the etcd pods.

volumeClaim required object

VolumeClaim can be used to configure the persistent volume claim.

enabled required boolean true

Enabled enables deploying a persistent volume claim.

accessModes required string[] [ReadWriteOnce]

AccessModes are the persistent volume claim access modes.

retentionPolicy required string Retain

RetentionPolicy is the persistent volume claim retention policy.

size required string 5Gi

Size is the persistent volume claim storage size.

storageClass required string

StorageClass is the persistent volume claim storage class.

volumeClaimTemplates required object[] []

VolumeClaimTemplates defines the volumeClaimTemplates for the statefulSet

addVolumes required object[] []

AddVolumes defines extra volumes for the pod

addVolumeMounts required object[]

AddVolumeMounts defines extra volume mounts for the container

name required string

This must match the Name of a Volume.

readOnly required boolean

Mounted read-only if true, read-write otherwise (false or unspecified). Defaults to false.

mountPath required string

Path within the container at which the volume should be mounted. Must not contain ':'.

subPath required string

Path within the volume from which the container's volume should be mounted. Defaults to "" (volume's root).

mountPropagation required string

mountPropagation determines how mounts are propagated from the host to container and the other way around. When not set, MountPropagationNone is used. This field is beta in 1.10.

subPathExpr required string

Expanded path within the volume from which the container's volume should be mounted. Behaves similarly to SubPath but environment variable references $(VAR_NAME) are expanded using the container's environment. Defaults to "" (volume's root). SubPathExpr and SubPath are mutually exclusive.

annotations required object {}

Annotations are extra annotations for this resource.

labels required object {}

Labels are extra labels for this resource.

service required object

Service holds options for the external etcd service.

enabled required boolean true

Enabled defines if the etcd service should be deployed

annotations required object {}

Annotations are extra annotations for the external etcd service

headlessService required object

HeadlessService holds options for the external etcd headless service.

annotations required object {}

Annotations are extra annotations for the external etcd headless service