K8s（二）Pod资源 |
您所在的位置：网站首页 › k8s节点亲和权重 › K8s（二）Pod资源 |
K8s（二）Pod资源
|
目录 node调度策略nodeName和nodeSelector 指定nodeName 指定nodeSelector node亲和性 node节点亲和性 硬亲和性 软亲和性 污点与容忍度 本文主要介绍了在pod中，与node相关的调度策略，亲和性，污点与容忍度等的内容 node调度策略nodeName和nodeSelector在创建pod等资源时，可以通过调整字段进行node调度，指定资源调度到满足何种条件的node 指定nodeName vim testpod1.yaml apiVersion: v1 kind: Pod metadata: name: testpod1 namespace: default labels: app: tomcat spec: nodeName: ws-k8s-node1 #增加字段，将这个pod调度到node1 containers: - name: test image: docker.io/library/tomcat imagePullPolicy: IfNotPresent kubectl apply -f testpod1.yaml kubectl get pods #可以看到已经调度到node1上了 testpod1 1/1 Running 0 116s 10.10.179.9 ws-k8s-node1 指定nodeSelector vim testpod2.yaml apiVersion: v1 kind: Pod metadata: name: testpod2 namespace: default labels: app: tomcat spec: nodeSelector: #添加nodeSelector选项， admin: ws #调度到具有admin=ws标签的node上 containers: - name: test image: docker.io/library/tomcat imagePullPolicy: IfNotPresent kubectl apply -f testpod2.yaml 但因为我没有admin=ws标签的node，所以应用后pod处于pending状态 #现在我给node1的节点打个标签 #kubectl --help | grep -i label #kubectl label --help Examples: # Update pod 'foo' with the label 'unhealthy' and the value 'true' #kubectl label pods foo unhealthy=true kubectl label nodes ws-k8s-node1 admin=ws #node/ws-k8s-node1 labeled #调度情况恢复正常 kubectl get pods | grep testpod2 testpod2 1/1 Running 0 11m #删除node标签 kubectl label nodes ws-k8s-node1 admin- #删除testpod2 kubectl delete pods testpod2
如果同时使用nodeName和nodeSelector，则会报错亲和性错误，无法正常部署； 如果nodeName和nodeSelector指定的node同时满足这两项的条件，就可以部署 node亲和性亲和性在Kubernetes中起着重要作用，通过定义规则和条件，它允许我们实现精确的Pod调度、资源优化、高性能计算以及容错性和可用性的增强。通过利用亲和性，我们可以更好地管理和控制集群中的工作负载，并满足特定的业务需求。 #查看帮助 kubectl explain pods.spec.affinity RESOURCE: affinity DESCRIPTION: If specified, the pod's scheduling constraints Affinity is a group of affinity scheduling rules. FIELDS: nodeAffinity #node亲和性 Describes node affinity scheduling rules for the pod. podAffinity #pod亲和性 Describes pod affinity scheduling rules (e.g. co-locate this pod in the same node, zone, etc. as some other pod(s)). podAntiAffinity #pod反亲和性 Describes pod anti-affinity scheduling rules (e.g. avoid putting this pod in the same node, zone, etc. as some other pod(s)). node节点亲和性在创建pod时，会根据nodeaffinity来寻找最适合该pod的条件的node #查找帮助 kubectl explain pods.spec.affinity.nodeAffinity KIND: Pod VERSION: v1 RESOURCE: nodeAffinity DESCRIPTION: Describes node affinity scheduling rules for the pod. Node affinity is a group of node affinity scheduling rules. FIELDS: preferredDuringSchedulingIgnoredDuringExecution requiredDuringSchedulingIgnoredDuringExecution #软亲和性，如果所有都不满足条件，也会找一个节点将就 preferredDuringSchedulingIgnoredDuringExecution #硬亲和性，必须满足，如果不满足则不找节点，宁缺毋滥 requiredDuringSchedulingIgnoredDuringExecution 硬亲和性 kubectl explain pods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution #nodeSelectorTerms -required- # Required. A list of node selector terms. The terms are ORed. kubectl explain pods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms FIELDS: matchExpressions #匹配表达式 A list of node selector requirements by node's labels. matchFields #匹配字段 A list of node selector requirements by node's fields. #匹配表达式 kubectl explain pods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms.matchExpressions key -required- operator -required- values #可用operator - `"DoesNotExist"` - `"Exists"` - `"Gt"` - `"In"` - `"Lt"` - `"NotIn"` # vim ying-pod.yaml apiVersion: v1 kind: Pod metadata: name: ying-pod labels: app: tomcat user: ws spec: affinity: nodeAffinity: requiredDuringSchedulingIgnoredDuringExecution: nodeSelectorTerms: - matchExpressions: - key: name #去找key=name opertor: In # name = ws或=wws values: - ws - wss containers: - name: test1 namespace: default image: docker.io/library/tomcat imagePullPolicy: IfNotPresent kubectl apply -f ying-pod.yaml #需要name=ws或name=wws，但是没有节点有标签，而且是硬亲和 #所以pod会处于pending状态 kubectl get pods | grep ying ying-pod 0/1 Pending 0 15m #修改node标签 kubectl label nodes ws-k8s-node1 name=ws #开始构建，并且已经到node1节点了 kubectl get pod -owide | grep ying ying-pod 0/1 ContainerCreating 0 80s ws-k8s-node1 #删除标签 kubectl label nodes ws-k8s-node1 name- 软亲和性 vim ruan-pod.yaml apiVersion: v1 kind: Pod metadata: name: ruan-pod namespace: default spec: containers: - name: test image: docker.io/library/alpine imagePullPolicy: IfNotPresent affinity: nodeAffinity: preferredDuringSchedulingIgnoredDuringExecution: #必选preference和weight - preference: matchExpressions: - key: name operate: In #还有Exists，Gt，Lt，NotIn等 values: - ws weight: 50 #软亲和性有“权重”说法，权重更高的更优先，范围1-100 - preference: matchExpressions: - key: name operate: In values: - wws weight: 70 #设置的比上面的高，用以做测试 kubectl apply -f ruan-pod.yaml #不满足条件，所以随机找一个进行调度，能看到调度到了node2上 kubectl get pod -owide | grep ruan ruan-pod 0/1 ContainerCreating 0 3m24s ws-k8s-node2 #修改node1的标签name=ws kubectl label nodes ws-k8s-node1 name=ws kubectl delete -f ruan-pod.yaml #删除再重新创建 kubectl apply -f ruan-pod.yaml kubectl get pods -owide | grep ruan #调整到了node1上 ruan-pod 0/1 ContainerCreating 0 2s ws-k8s-node1 #修改node2的标签name=wws，此时node2权重比node1高 kubectl label nodes ws-k8s-node2 name=wss kubectl delete -f ruan-pod.yaml kubectl apply -f ruan-pod.yaml kubectl get pods -owide | grep ruan #没有变化，还在node1 ruan-pod 0/1 ContainerCreating 0 4m29s ws-k8s-node1 #因为yaml的匹配顺序，已经匹配到了name=ws，如果没有另外标签不同的则不会变化 #修改ruan-pod.yaml ... - preference: matchExpressions: - key: name operator: In values: - ws weight: 50 - preference: matchExpressions: - key: names operator: In values: - wws weight: 70 ... #添加node2标签name1=wws，权重比node1高，且标签key不同 kubectl label nodes ws-k8s-node2 names=wws kubectl delete -f ruan-pod.yaml kubectl apply -f ruan-pod.yaml kubectl get po -owide | grep ruan #可以看到ruan-pod已经回到了node2上 ruan-pod 0/1 ContainerCreating 0 3m47s ws-k8s-node2 #清理环境 kubectl label nodes ws-k8s-node1 name- kubectl label nodes ws-k8s-node2 names- kubectl delete -f ruan-pod.yaml kubectl delete -f ying-pod.yaml --fore --grace-period=0 #强制删除 污点与容忍度污点类似于标签，可以给node打taints，如果pod没有对node上的污点有容忍，那么就不会调度到该node上。 在创建pod时可以通过tolerations来定义pod对于污点的容忍度 #查看node上的污点 #master节点是默认有污点 kubectl describe node ws-k8s-master1 | grep -i taint Taints: node-role.kubernetes.io/control-plane:NoSchedule #node默认没有污点 kubectl describe node ws-k8s-node1 | grep -i taint Taints: #kubectl explain nodes.spec.taints查看帮助 kubectl explain nodes.spec.taints.effect 1.NoExecute 对已调度的pod不影响，仅对新需要调度的pod进行影响 2.NoSchedule 对已调度和新调度的pod都会有影响 3.PreferNoSchedule 软性的NoSchedule，就算不满足条件也可以调度到不容忍的node上 #查看当前master节点pod容忍情况 kubectl get pods -n kube-system -owide kubectl describe pods kube-proxy-bg7ck -n kube-system | grep -i tolerations -A 10 Tolerations: op=Exists node.kubernetes.io/disk-pressure:NoSchedule op=Exists node.kubernetes.io/memory-pressure:NoSchedule op=Exists node.kubernetes.io/network-unavailable:NoSchedule op=Exists node.kubernetes.io/not-ready:NoExecute op=Exists node.kubernetes.io/pid-pressure:NoSchedule op=Exists node.kubernetes.io/unreachable:NoExecute op=Exists node.kubernetes.io/unschedulable:NoSchedule op=Exists Events: #给node1打一个污点，使其不接受 kubectl taint node ws-k8s-node1 user=ws:NoSchedule #创建wudian.yaml进行测试 cat > wudian.yaml wudian2.yaml wudian3.yaml |
【本文地址】
今日新闻 |
推荐新闻 |