charts/bitnami/metrics-server

Metrics Server

Metrics Server is a cluster-wide aggregator of resource usage data. Metrics Server collects metrics from the Summary API, exposed by Kubelet on each node.

TL;DR

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/metrics-server

Introduction

This chart bootstraps a Metrics Server deployment on a Kubernetes cluster using the Helm package manager.

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters. This Helm chart has been tested on top of Bitnami Kubernetes Production Runtime (BKPR). Deploy BKPR to get automated TLS certificates, logging and monitoring for your applications.

Prerequisites

• Kubernetes 1.12+
• Helm 3.1.0

Installing the Chart

To install the chart with the release name my-release:

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/metrics-server

These commands deploy Metrics Server on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip

: List all releases using helm list

Uninstalling the Chart

To uninstall/delete the my-release deployment:

$ helm delete my-release

The command removes all the Kubernetes components associated with the chart and deletes the release.

Parameters

Global parameters

Name	Description	Value
global.imageRegistry	Global Docker image registry	""
global.imagePullSecrets	Global Docker registry secret names as an array	[]

Common parameters

Name	Description	Value
nameOverride	String to partially override common.names.fullname template (will maintain the release name)	""
fullnameOverride	String to fully override common.names.fullname template	""
commonLabels	Add labels to all the deployed resources	{}
commonAnnotations	Add annotations to all the deployed resources	{}

Metrics Server parameters

Name	Description	Value
image.registry	Metrics Server image registry	docker.io
image.repository	Metrics Server image repository	bitnami/metrics-server
image.tag	Metrics Server image tag (immutable tags are recommended)	0.5.1-debian-10-r30
image.pullPolicy	Metrics Server image pull policy	IfNotPresent
image.pullSecrets	Metrics Server image pull secrets	[]
hostAliases	Add deployment host aliases	[]
replicas	Number of metrics-server nodes to deploy	1
updateStrategy.type	Set up update strategy for metrics-server installation.	RollingUpdate
rbac.create	Enable RBAC authentication	true
serviceAccount.create	Specifies whether a ServiceAccount should be created	true
serviceAccount.name	The name of the ServiceAccount to create	""
serviceAccount.automountServiceAccountToken	Automount API credentials for a service account	true
apiService.create	Specifies whether the v1beta1.metrics.k8s.io API service should be created. You can check if it is needed with kubectl get --raw "/apis/metrics.k8s.io/v1beta1/nodes".	false
apiService.insecureSkipTLSVerify	Specifies whether to skip self-verifying self-signed TLS certificates. Set to "false" if you are providing your own certificates.	true
apiService.caBundle	A base64-encoded string of concatenated certificates for the CA chain for the APIService.	""
securePort	Port where metrics-server will be running	8443
hostNetwork	Enable hostNetwork mode	false
dnsPolicy	Default dnsPolicy setting	ClusterFirst
command	Override default container command (useful when using custom images)	["metrics-server"]
extraArgs	Extra arguments to pass to metrics-server on start up	{}
podLabels	Pod labels	{}
podAnnotations	Pod annotations	{}
priorityClassName	Priority class for pod scheduling	""
podAffinityPreset	Pod affinity preset. Ignored if affinity is set. Allowed values: soft or hard	""
podAntiAffinityPreset	Pod anti-affinity preset. Ignored if affinity is set. Allowed values: soft or hard	soft
podDisruptionBudget.enabled	Create a PodDisruptionBudget	false
podDisruptionBudget.minAvailable	Minimum available instances	""
podDisruptionBudget.maxUnavailable	Maximum unavailable instances	""
nodeAffinityPreset.type	Node affinity preset type. Ignored if affinity is set. Allowed values: soft or hard	""
nodeAffinityPreset.key	Node label key to match. Ignored if affinity is set.	""
nodeAffinityPreset.values	Node label values to match. Ignored if affinity is set.	[]
affinity	Affinity for pod assignment	{}
topologySpreadConstraints	Topology spread constraints for pod	[]
nodeSelector	Node labels for pod assignment	{}
tolerations	Tolerations for pod assignment	[]
service.type	Kubernetes Service type	ClusterIP
service.port	Kubernetes Service port	443
service.nodePort	Kubernetes Service port	""
service.loadBalancerIP	LoadBalancer IP if Service type is LoadBalancer	""
service.annotations	Annotations for the Service	{}
service.labels	Labels for the Service	{}
resources.limits	The resources limits for the container	{}
resources.requests	The requested resources for the container	{}
livenessProbe.enabled	Enable livenessProbe	true
livenessProbe.httpGet.path	Request path for livenessProbe	/livez
livenessProbe.httpGet.port	Port for livenessProbe	https
livenessProbe.httpGet.scheme	Scheme for livenessProbe	HTTPS
livenessProbe.periodSeconds	Period seconds for livenessProbe	10
livenessProbe.failureThreshold	Failure threshold for livenessProbe	3
readinessProbe.enabled	Enable readinessProbe	true
readinessProbe.httpGet.path	Request path for readinessProbe	/readyz
readinessProbe.httpGet.port	Port for readinessProbe	https
readinessProbe.httpGet.scheme	Scheme for livenessProbe	HTTPS
readinessProbe.periodSeconds	Period seconds for readinessProbe	10
readinessProbe.failureThreshold	Failure threshold for readinessProbe	3
customLivenessProbe	Custom Liveness probes for metrics-server	{}
customReadinessProbe	Custom Readiness probes metrics-server	{}
containerSecurityContext.enabled	Enable Container security context	true
containerSecurityContext.readOnlyRootFilesystem	ReadOnlyRootFilesystem for the container	false
containerSecurityContext.runAsNonRoot	Run containers as non-root users	true
podSecurityContext.enabled	Pod security context	false
extraVolumes	Extra volumes	[]
extraVolumeMounts	Mount extra volume(s)	[]
extraContainers	Extra containers to run within the pod	{}

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

$ helm install my-release \
  --set rbac.create=true bitnami/metrics-server

The above command enables RBAC authentication.

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

$ helm install my-release -f values.yaml bitnami/metrics-server

Tip

: You can use the default values.yaml

Configuration and installation details

Rolling vs Immutable tags

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

Enable RBAC security

In order to enable Role-Based Access Control (RBAC) for Metrics Server, use the following parameter: rbac.create=true.

Configure certificates

If you are providing your own certificates for the API Service, set insecureSkipTLSVerify to "false", and provide a caBundle consisting of the base64-encoded certificate chain.

Set Pod affinity

This chart allows you to set custom Pod affinity using the affinity parameter. Find more information about Pod affinity in the Kubernetes documentation.

As an alternative, you can use one of the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common chart. To do so, set the podAffinityPreset, podAntiAffinityPreset, or nodeAffinityPreset parameters.

Troubleshooting

Find more information about how to deal with common errors related to Bitnami’s Helm charts in this troubleshooting guide.

Upgrading

To 5.2.0

This version introduces bitnami/common, a library chart as a dependency. More documentation about this new utility could be found here. Please, make sure that you have updated the chart dependencies before executing any upgrade.

To 5.0.0

On November 13, 2020, Helm v2 support formally ended. This major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

Learn more about this change and related upgrade considerations.

To 4.0.0

Backwards compatibility is not guaranteed unless you modify the labels used on the chart's deployments. Use the workaround below to upgrade from versions previous to 4.0.0. The following example assumes that the release name is metrics-server:

$ kubectl delete deployment metrics-server --cascade=false
$ helm upgrade metrics-server bitnami/metrics-server

To 2.0.0

Backwards compatibility is not guaranteed unless you modify the labels used on the chart's deployments. Use the workaround below to upgrade from versions previous to 2.0.0. The following example assumes that the release name is metrics-server:

$ kubectl patch deployment metrics-server --type=json -p='[{"op": "remove", "path": "/spec/selector/matchLabels/chart"}]'