Kubernetes 标签

• https://kubernetes.io/docs/reference/kubernetes-api/labels-annotations-taints
• https://kubernetes.io/docs/reference/labels-annotations-taints/

节点标签

• kubernetes.io/ingress.class

label	demo	desc
k3s.io/hostname	node-3
k3s.io/internal-ip	10.10.1.1
kubernetes.io/arch	amd64	+v1.14
kubernetes.io/hostname	node-3
kubernetes.io/os	linux	+v1.14
node-role.kubernetes.io/<role>	true
node-role.kubernetes.io/master	true	Master node
node-role.kubernetes.io/control-plane	true	cp
node.kubernetes.io/instance-type	k3s
topology.kubernetes.io/region		+v1.17
topology.kubernetes.io/zone		+v1.17

# 设置 node role 为 worker
# role 名字任意
# value 不重要，主要是存在该 label
kubectl label node node-2 node-role.kubernetes.io/worker=true
# 规划 region 和 zone
kubectl label node master-1 topology.kubernetes.io/region=sh
kubectl label node master-1 topology.kubernetes.io/zone=sh-dc1

Deprecated

label	demo	desc
beta.kubernetes.io/arch	amd64	!v1.14, -v1.18
beta.kubernetes.io/instance-type	k3s	!v1.17
beta.kubernetes.io/os	linux	!v1.14, -v1.18
failure-domain.beta.kubernetes.io/region		!v1.17
failure-domain.beta.kubernetes.io/zone		!v1.17

资源标签

kind	annotation	demo	desc
StorageClass	storageclass.kubernetes.io/is-default-class	true	默认 StorageClass
VolumeSnapshotClass	snapshot.storage.kubernetes.io/is-default-class	true
Ingress	kubernetes.io/ingress.class	nginx	废弃,spec.ingressClassName
IngressClass	ingressclass.kubernetes.io/is-default-class	true

kind	label	demo	desc
Namespace	kubernetes.io/metadata.name	kube-system	namespace 的名字

kubectl get storageclass

# 取消 sc 的默认值
kubectl patch storageclass local-path -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"false"}}}'
# 设置默认
kubectl patch storageclass longhorn -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'

应用标签

• Recommanded Lables
• Helm Labels

label	example
app.kubernetes.io/name	mysql
app.kubernetes.io/instance	mysql-abcd
app.kubernetes.io/version	5.7
app.kubernetes.io/component	database
app.kubernetes.io/part-of	ghost
app.kubernetes.io/managed-by	helm

podAntiAffinity:
  preferredDuringSchedulingIgnoredDuringExecution:
    - weight: 100
      podAffinityTerm:
        labelSelector:
          matchLabels:
            app.kubernetes.io/component: prometheus
            app.kubernetes.io/instance: kube-prometheus
            app.kubernetes.io/name: kube-prometheus
        topologyKey: kubernetes.io/hostname

Helm 标签

label	example
app.kubernetes.io/managed-by	Helm

# 资源 label
labels:
  app.kubernetes.io/component: controller
  app.kubernetes.io/instance: ingress-nginx
  app.kubernetes.io/managed-by: Helm
  app.kubernetes.io/name: ingress-nginx
  app.kubernetes.io/version: 0.35.0
  helm.sh/chart: ingress-nginx-2.16.0

# selector label
matchLabels:
  app.kubernetes.io/component: controller
  app.kubernetes.io/instance: ingress-nginx
  app.kubernetes.io/name: ingress-nginx

Helm 注解

annotation	value	desc
meta.helm.sh/release-name	linkerd2
meta.helm.sh/release-namespace	linkerd

LabelSelector

• labelSelector - 数组内为 OR 关系
• matchLabels
  • label: value
• matchExpressions - 数组内为 AND 关系
  • key
  • operator: In, NotIn, Exists, DoesNotExist
  • values: []

dashboardLabelSelector: # OR
  - matchExpressions: # AND
      - { key: app, operator: In, values: [grafana] }
      - { key: group, operator: In, values: [grafana] }

FAQ

region vs zone

• region - 区域
  • 地区/zone 集合
  • 同区域 高带宽、低延迟
• zone - 可用区 <region>-<zone>
  • us-central1
  • us-central1-a - zone 内区域
• https://cloud.google.com/compute/docs/regions-zones
• https://kubernetes.io/docs/setup/best-practices/multiple-zones/