StatefulSet
The vCluster control plane is deployed as a StatefulSet, since vCluster requires a PersistentVolume resource to store data across restarts. When you configure statefulSet.persistence.volumeClaim.enabled: false
or you don't configure statefulSet.persistence.volumeClaimTemplates
, vCluster is deployed as a Deployment
.
High availability​
- The
highAvailability
settings let you run more than one pod for the vCluster control plane, with one running as the leader. - If the leader crashes, is unhealthy, or restarts, more pods take over leadership, depending on the number of replicas.
- Adjusting the leaseDuration / renewDeadline / retryPeriod changes the leader election behavior (how often a leader is renewed & retries when it cannot be renewed)
Scheduling​
scheduling
configures various scheduler behavior for different purposes. Examples of each follow:
nodeSelector
: Matches labels on nodes to make the scheduler "prefer" scheduling the virtual cluster pods on certain nodes. Do this to:- Target nodes in a region.
- Target a specific architecture or machine class.
affinity
: Value can be affinity (attract the pod) or anti-affinity (repel the pod).- Use anti-affinity to spread pods away from each other. A common technique is to make virtual cluster pods repel each other so that they are not scheduled on the same nodes. This increases resiliency in the event a node is scaled down or replaced by a cloud provider.
- Use affinity to group certain pods together to reduce network latency for critical services
tolerations
: Another method of influencing where the scheduler places pods. A common use is to "taint" nodes for non-virtual-cluster workloads and make virtual cluster workloads "tolerate" the taint. This results in separating critical apps from the more ephemeral vCluster instances.priorityClassName
: See Pod Priority and Preemption.podManagementPolicy
: See Pod Management Policies.topologySpreadConstraints
: See Pod Topology Spread Constraints.- Similar to podAffinity & podAntiAffinity in some ways. See Comparison with podAffinity and podAntiAffinity.
Re-using existing PersistenceVolumeClaim​
It is possible to pre-provision a PersistenceVolumeClaim, and then configure vCluster to use it.
To do that, set existing claim name in the chart values controlPlane.statefulSet.persistence.dataVolume
under persistenceVolumeClaim.claimName
.
controlPlane:
statefulSet:
persistence:
dataVolume:
- name: data
persistentVolumeClaim:
claimName: my-existing-pvc
Config reference​
statefulSet
required object pro​
StatefulSet defines options for vCluster statefulSet deployed by Helm.
statefulSet
required object pro​highAvailability
required object pro​
HighAvailability holds options related to high availability.
highAvailability
required object pro​replicas
required integer 1 pro​
Replicas is the amount of replicas to use for the statefulSet.
replicas
required integer 1 pro​leaseDuration
required integer 60 pro​
LeaseDuration is the time to lease for the leader.
leaseDuration
required integer 60 pro​renewDeadline
required integer 40 pro​
RenewDeadline is the deadline to renew a lease for the leader.
renewDeadline
required integer 40 pro​retryPeriod
required integer 15 pro​
RetryPeriod is the time until a replica will retry to get a lease.
retryPeriod
required integer 15 pro​resources
required object pro​
Resources are the resource requests and limits for the statefulSet container.
resources
required object pro​scheduling
required object pro​
Scheduling holds options related to scheduling.
scheduling
required object pro​nodeSelector
required object {} pro​
NodeSelector is the node selector to apply to the pod.
nodeSelector
required object {} pro​affinity
required object {} pro​
Affinity is the affinity to apply to the pod.
affinity
required object {} pro​tolerations
required object[] [] pro​
Tolerations are the tolerations to apply to the pod.
tolerations
required object[] [] pro​priorityClassName
required string pro​
PriorityClassName is the priority class name for the the pod.
priorityClassName
required string pro​podManagementPolicy
required string Parallel pro​
PodManagementPolicy is the statefulSet pod management policy.
podManagementPolicy
required string Parallel pro​topologySpreadConstraints
required object[] [] pro​
TopologySpreadConstraints are the topology spread constraints for the pod.
topologySpreadConstraints
required object[] [] pro​security
required object pro​
Security defines pod or container security context.
security
required object pro​podSecurityContext
required object {} pro​
PodSecurityContext specifies security context options on the pod level.
podSecurityContext
required object {} pro​containerSecurityContext
required object map[allowPrivilegeEscalation:false runAsGroup:0 runAsUser:0] pro​
ContainerSecurityContext specifies security context options on the container level.
containerSecurityContext
required object map[allowPrivilegeEscalation:false runAsGroup:0 runAsUser:0] pro​probes
required object pro​
Probes enables or disables the main container probes.
probes
required object pro​livenessProbe
required object pro​
LivenessProbe specifies if the liveness probe for the container should be enabled
livenessProbe
required object pro​enabled
required boolean true pro​
Enabled defines if this option should be enabled.
enabled
required boolean true pro​persistence
required object pro​
Persistence defines options around persistence for the statefulSet.
persistence
required object pro​volumeClaim
required object pro​
VolumeClaim can be used to configure the persistent volume claim.
volumeClaim
required object pro​enabled
required string|boolean auto pro​
Enabled enables deploying a persistent volume claim. If auto, vCluster will automatically determine
based on the chosen distro and other options if this is required.
enabled
required string|boolean auto pro​accessModes
required string[] [ReadWriteOnce] pro​
AccessModes are the persistent volume claim access modes.
accessModes
required string[] [ReadWriteOnce] pro​retentionPolicy
required string Retain pro​
RetentionPolicy is the persistent volume claim retention policy.
retentionPolicy
required string Retain pro​size
required string 5Gi pro​
Size is the persistent volume claim storage size.
size
required string 5Gi pro​storageClass
required string pro​
StorageClass is the persistent volume claim storage class.
storageClass
required string pro​volumeClaimTemplates
required object[] [] pro​
VolumeClaimTemplates defines the volumeClaimTemplates for the statefulSet
volumeClaimTemplates
required object[] [] pro​dataVolume
required object[] [] pro​
Allows you to override the dataVolume. Only works correctly if volumeClaim.enabled=false.
dataVolume
required object[] [] pro​binariesVolume
required object[] [map[emptyDir:map[] name:binaries]] pro​
BinariesVolume defines a binaries volume that is used to retrieve
distro specific executables to be run by the syncer controller.
This volume doesn't need to be persistent.
binariesVolume
required object[] [map[emptyDir:map[] name:binaries]] pro​addVolumes
required object[] [] pro​
AddVolumes defines extra volumes for the pod
addVolumes
required object[] [] pro​addVolumeMounts
required object[] pro​
AddVolumeMounts defines extra volume mounts for the container
addVolumeMounts
required object[] pro​name
required string pro​
This must match the Name of a Volume.
name
required string pro​readOnly
required boolean pro​
Mounted read-only if true, read-write otherwise (false or unspecified).
Defaults to false.
readOnly
required boolean pro​mountPath
required string pro​
Path within the container at which the volume should be mounted. Must
not contain ':'.
mountPath
required string pro​subPath
required string pro​
Path within the volume from which the container's volume should be mounted.
Defaults to "" (volume's root).
subPath
required string pro​mountPropagation
required string pro​
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.
mountPropagation
required string pro​subPathExpr
required string pro​
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.
subPathExpr
required string pro​enableServiceLinks
required boolean true pro​
EnableServiceLinks for the StatefulSet pod
enableServiceLinks
required boolean true pro​annotations
required object {} pro​
Annotations are extra annotations for this resource.
annotations
required object {} pro​labels
required object {} pro​
Labels are extra labels for this resource.
labels
required object {} pro​pods
required object pro​
Additional labels or annotations for the statefulSet pods.
pods
required object pro​image
required object pro​
Image is the image for the controlPlane statefulSet container
image
required object pro​registry
required string ghcr.io pro​
Configure the registry of the container image, e.g. my-registry.com or ghcr.io
It defaults to ghcr.io and can be overriding either by using this field or controlPlane.advanced.defaultImageRegistry
registry
required string ghcr.io pro​repository
required string loft-sh/vcluster-pro pro​
Configure the repository of the container image, e.g. my-repo/my-image.
It defaults to the vCluster pro repository that includes the optional pro modules that are turned off by default.
If you still want to use the pure OSS build, use 'loft-sh/vcluster-oss' instead.
repository
required string loft-sh/vcluster-pro pro​tag
required string pro​
Tag is the tag of the container image, e.g. latest
tag
required string pro​imagePullPolicy
required string pro​
ImagePullPolicy is the policy how to pull the image.
imagePullPolicy
required string pro​workingDir
required string pro​
WorkingDir specifies in what folder the main process should get started.
workingDir
required string pro​command
required string[] [] pro​
Command allows you to override the main command.
command
required string[] [] pro​args
required string[] [] pro​
Args allows you to override the main arguments.
args
required string[] [] pro​env
required object[] [] pro​
Env are additional environment variables for the statefulSet container.
env
required object[] [] pro​dnsPolicy
required string pro​
Set DNS policy for the pod.
dnsPolicy
required string pro​dnsConfig
required object pro​
Specifies the DNS parameters of a pod.
dnsConfig
required object pro​nameservers
required string[] pro​
A list of DNS name server IP addresses.
This will be appended to the base nameservers generated from DNSPolicy.
Duplicated nameservers will be removed.
nameservers
required string[] pro​searches
required string[] pro​
A list of DNS search domains for host-name lookup.
This will be appended to the base search paths generated from DNSPolicy.
Duplicated search paths will be removed.
searches
required string[] pro​options
required object[] pro​
A list of DNS resolver options.
This will be merged with the base options generated from DNSPolicy.
Duplicated entries will be removed. Resolution options given in Options
will override those that appear in the base DNSPolicy.
options
required object[] pro​