README.md

ntp-exporter

Prometheus exporter that checks the drift of Kubernetes node's clock against a given NTP server or servers

TL;DR;

helm repo add christianhuth https://charts.christianhuth.de
helm repo update
helm install my-release christianhuth/ntp-exporter

Introduction

This chart bootstraps a NTP-Exporter for Prometheus using the Helm package manager.

Prerequisites

• Kubernetes 1.19+
• Prometheus

Installing the Chart

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

helm repo add christianhuth https://charts.christianhuth.de
helm repo update
helm install my-release christianhuth/ntp-exporter

These commands deploy the NTP-Exporter on the Kubernetes cluster in the default configuration. The Values section lists the values that can be configured during installation.

Tip: List all releases using helm list

Uninstalling the Chart

To uninstall the my-release deployment:

helm uninstall my-release

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

Values

Key	Type	Default	Description
affinity	object	{}	Affinity settings for pod assignment
fullnameOverride	string	""	String to fully override "ntp-exporter.fullname"
image.pullPolicy	string	"Always"	image pull policy
image.registry	string	"ghcr.io"	image registry
image.repository	string	"sapcc/ntp_exporter"	image repository
image.tag	string	"v2.9.0"	Overrides the image tag
imagePullSecrets	list	[]	If defined, uses a Secret to pull an image from a private Docker registry or repository.
ingress.annotations	object	{}
ingress.className	string	""
ingress.enabled	bool	false
ingress.hosts[0].host	string	"chart-example.local"
ingress.hosts[0].paths[0].path	string	"/"
ingress.hosts[0].paths[0].pathType	string	"ImplementationSpecific"
ingress.tls	list	[]
nameOverride	string	""	Provide a name in place of ntp-exporter
nodeSelector	object	{}	Node labels for pod assignment
ntp.config.highDriftThreshold	string	"10ms"	High drift threshold
ntp.config.measurementDuration	string	"30s"	Duration of measurements in case of high (>10ms) drift
ntp.config.protocolVersion	string	"4"	NTP protocol version to use
ntp.exporter.path	string	"/metrics"	Path under which to expose metrics
ntp.exporter.port	int	9559	The port the exporter will listen on
ntp.server	string	""	NTP server to query for time
ntp.source	string	"cli"	source of information about ntp server. Valid options are cli and http
podAnnotations	object	{}	Annotations to be added to pods
podMonitor.additionalLabels	object	{}	Prometheus PodMonitor labels
podMonitor.enabled	bool	false	Enable a prometheus PodMonitor
podMonitor.interval	string	"30s"	Prometheus PodMonitor interval
podMonitor.metricRelabelings	list	[]	Prometheus [MetricRelabelConfigs] to apply to samples before ingestion
podMonitor.namespace	string	""	Prometheus PodMonitor namespace
podMonitor.relabelings[0].action	string	"replace"
podMonitor.relabelings[0].sourceLabels[0]	string	"__meta_kubernetes_pod_node_name"
podMonitor.relabelings[0].targetLabel	string	"node"
podMonitor.scrapeTimeout	string	""	Prometheus PodMonitor scrapeTimeout, cannot be longer than the scrape interval
podMonitor.selector	object	{}	Prometheus PodMonitor selector
podSecurityContext	object	see values.yaml	pod-level security context
prometheusRule.defaultRules.absence.enabled	bool	true	Enable the rule that alerts if no metrics are scraped from ntp-exporter
prometheusRule.defaultRules.absence.rule	object	see values.yaml for definition	The rule definition for clock drift alerting
prometheusRule.defaultRules.clockDrift.enabled	bool	true	Enable the rule that alerts on high clock drift
prometheusRule.defaultRules.clockDrift.rule	object	see values.yaml for definition	The rule definition for clock drift alerting
prometheusRule.defaultRules.enabled	bool	true	Enable the default rules that alert on clock drift and metrics absence
prometheusRule.enabled	bool	false	Enable a PrometheusRule
prometheusRule.rules	list	[]	List of additional rules
resources	object	see values.yaml	Resource limits and requests for the headwind pods.
route.main.additionalRules	list	[]	Additional custom rules that can be added to the route
route.main.annotations	object	{}	Add annotations to the route
route.main.apiVersion	string	"gateway.networking.k8s.io/v1"	Set the route apiVersion, e.g. gateway.networking.k8s.io/v1 or gateway.networking.k8s.io/v1alpha2
route.main.enabled	bool	false	Enables or disables the route
route.main.filters	list	[]	Filters define the filters that are applied to requests that match this rule.
route.main.hostnames	list	[]	Hostnames to be matched
route.main.httpsRedirect	bool	false	adds a filter for redirecting to https (HTTP 301 Moved Permanently). To redirect HTTP traffic to HTTPS, you need to have a Gateway with both HTTP and HTTPS listeners. Matches and filters do not take effect if enabled. Ref. https://gateway-api.sigs.k8s.io/guides/http-redirect-rewrite/
route.main.kind	string	"HTTPRoute"	Set the route kind Valid options are GRPCRoute, HTTPRoute, TCPRoute, TLSRoute, UDPRoute
route.main.labels	object	{}	Add labels to the route
route.main.matches	list	see values.yaml	define conditions used for matching the rule against incoming HTTP requests.
route.main.parentRefs	list	[]	Parent references (Gateway)
route.main.timeouts	object	{}	defines the timeouts that can be configured for an HTTP request
securityContext	object	see values.yaml	container-level security context
service.port	int	80	Kubernetes port where service is exposed
service.type	string	"ClusterIP"	Kubernetes service type
serviceAccount.annotations	object	{}	Annotations to add to the service account
serviceAccount.create	bool	true	Specifies whether a service account should be created
serviceAccount.name	string	""	The name of the service account to use. If not set and create is true, a name is generated using the fullname template
tolerations	list	see values.yaml	Toleration labels for pod assignment

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

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 christianhuth/ntp-exporter