k8s 高级调度 亲和力和反亲和力、绑定标签、污点容忍污点
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文章目录
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1. 通过标签绑定
spec:
nodeSelector:
bigdata-node: bigdata
containers:
- env:
pod只能运行在有bigdata-node: bigdata 标签的node节点
2. 通过node name绑定
spec:
nodeName: test-oc08
containers:
- env:
pod只能运行在名为test-oc08节点上
3. node的亲和力
apiVersion: v1
kind: Pod
metadata:
name: with-node-affinity
spec:
affinity:
nodeAffinity: #节点选择
requiredDuringSchedulingIgnoredDuringExecution: #定义必要规则
nodeSelectorTerms:
- matchExpressions:
- key: e2e-az-NorthSouth #必须匹配的键/值对(标签)
operator: In
values:
- e2e-az-North #必须匹配的键/值对(标签
- e2e-az-South
containers:
- name: with-node-affinity
image: docker.io/ocpqe/hello-pod
该规则要求将pod放置在节点上,且节点的标签的关键字是e2e-az-NorthSouth
,其值是e2e-az-North或者e2e-az-South
- 您可以
In
在示例中看到正在使用的运算符。新的节点亲和力语法支持以下运算符:In,NotIn,Exists,DoesNotExist,Gt,Lt。您可以使用NotIn和DoesNotExist实现节点的反亲和行为,也可以使用节点异味来排斥特定节点的吊舱。 - 如果同时指定
nodeSelector
和nodeAffinity
,则必须同时满足两个条件,才能将Pod调度到候选节点上。 - 如果您指定了多个
nodeSelectorTerms
与nodeAffinity
类型相关联的类型,那么如果
nodeSelectorTerms可以满足其中之一,则可以将Pod调度到一个节点上。 - 如果您指定
matchExpressions
与关联的多个nodeSelectorTerms
,则只有在
matchExpressions满足所有条件后,才能将广告连播安排到一个节点上。 - 如果您删除或更改计划了pod的节点的标签,则pod不会被删除。换句话说,亲和性选择仅在安排豆荚时有效。
-
weight
在preferredDuringSchedulingIgnoredDuringExecution
的范围是从1-100。对于满足所有调度要求(资源请求,RequiredDuringScheduling亲缘关系表达式等)的每个节点,调度程序将通过遍历此字段的元素并在该节点的匹配项中添加“权重”来计算总和MatchExpressions。然后,将该分数与该节点的其他优先级功能的分数合并。总得分最高的节点是最优选的。
apiVersion: v1
kind: Pod
metadata:
name: with-node-affinity
spec:
affinity:
nodeAffinity:
preferredDuringSchedulingIgnoredDuringExecution: #定义首选规则
- weight: 1 #权重
preference:
matchExpressions:
- key: e2e-az-EastWest
operator: In
values:
- e2e-az-East
- e2e-az-West
containers:
- name: with-node-affinity
image: docker.io/ocpqe/hello-pod
该节点具有标签的关键字为e2e-az-EastWest且其值为e2e-az-East或者e2e-az-West是该Pod的首选项的节点
4. pod间亲和性和反亲和性
apiVersion: v1
kind: Pod
metadata:
name: with-pod-affinity
spec:
affinity:
podAffinity: #亲和性
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- key: security
operator: In
values:
- S1
topologyKey: failure-domain.beta.kubernetes.io/zone
containers:
- name: with-pod-affinity
image: docker.io/ocpqe/hello-pod
pod必须部署在一个节点上,这个节点上至少有一个正在运行的pod,这个pod中security=S1
apiVersion: v1
kind: Pod
metadata:
name: with-pod-antiaffinity
spec:
affinity:
podAntiAffinity: #反亲和性
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 100
podAffinityTerm:
labelSelector:
matchExpressions:
- key: security
operator: In
values:
- S2
topologyKey: kubernetes.io/hostname
containers:
- name: with-pod-affinity
image: docker.io/ocpqe/hello-pod
pod不太会部署在一个节点上,这个节点上正在运行的pod中有security=S2
5. node的污点
-
NoSchedule
#新pod不会被调到该节点,已经存在的pod不会影响 -
PreferNoSchedule
#新pod尽量避免不会调度到该节点,已经存在的pod不会影响 -
NoExecute
#新pod不会被调到该节点,已经存在的pod将会被删除
spec:
taints:
- effect: NoSchedule
key: key1
timeAdded: null
value: value1
给节点添加污点
spec:
tolerations:
- key: "key1"
operator: "Equal"
value: "value1"
effect: "NoSchedule"
6. 综合
spec:
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: nginx
operator: Exists
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchLabels:
app.kubernetes.io/instance: nginx
app.kubernetes.io/name: nginx
topologyKey: kubernetes.io/hostname
pod调度对有nginx为key的节点保持亲和,对存在标签app.kubernetes.io/instance: nginx
与app.kubernetes.io/name: nginx
以及存在key为kubernetes.io/hostname
的pod的节点表示反亲和