26Kubernetes资源pod污点和容忍度1

Kubernetes资源Pod污点和容忍度1目录Node节点亲和性01任务Node节点选择器02任务学习目标【知识目标】掌握Kubernetes资源对象pod的基本使用。【技能目标】能够掌握Kubernetes资源对象pod污点和容忍度。1node节点选择器1默认pod会根据schduler默认调度到随机的一个工作节点，使用pod中的nodeName或者nodeSelector字段指定要调度到的node节点。node节点选择器1nodeName指定pod节点运行在哪个具体node上把tomcat.tar.gz上传到node1和node2，手动解压：[root@node1~]#dockerload-itomcat.tar.gzLoadedimage:tomcat:8.5-jre8-alpine[root@node2~]#dockerload-itomcat.tar.gzLoadedimage:tomcat:8.5-jre8-alpine#把busybox.tar.gz上传到node1和node2，手动解压：[root@node1~]#dockerload-ibusybox.tar.gz[root@node2~]#dockerload-ibusybox.tar.gznode节点选择器nodeName1[root@master1~]#catpod-node.yamlspec:

nodeName:node1containers:-name:tomcat-pod-javaports:-containerPort:8080image:tomcat:8.5-jre8-alpineimagePullPolicy:IfNotPresent-name:busyboximage:busybox:latestcommand:-"/bin/sh"-"-c"-"sleep3600"node节点选择器nodeName1[root@master1~]#kubectlapply-fpod-node.yaml查看pod调度到哪个节点：[root@master1~]#kubectlgetpods-owideNAME

READY

STATUSRESTARTSAGEIP

NODE

NOMINATEDNODEREADINESSGATESdemo-pod1/1Running015m10.244.0.34node1<none>

<none>node节点选择器nodeName1nodeSelector指定pod调度到具有哪些标签的node节点上给node节点打标签，打个具有disk=ceph的标签：[root@master1~]#kubectllabelnodesnode2disk=cephnode/node2labelednode节点选择器nodeSelector1定义pod的时候指定要调度到具有disk=ceph标签的node上：[root@master1~]#catpod-1.yaml。。。spec:

nodeSelector:disk:cephcontainers:-name:tomcat-pod-javaports:-containerPort:8080image:tomcat:8.5-jre8-alpineimagePullPolicy:IfNotPresentnode节点选择器nodeSelector1[root@master1~]#kubectlapply-fpod-1.yaml查看pod调度到哪个节点：[root@master1~]#kubectlgetpods-owideNAME

READY

STATUSRESTARTSAGEIP

NODE

NOMINATEDNODEREADINESSGATESdemo-pod-11/1Running018m10.244.0.35node2

<none>

<none>node节点选择器nodeSelector2node节点亲和性2affinity：指定Pod亲和性调度规则节点亲和性nodeAffinity：用来控制Pod要部署在哪些节点上，以及不能部署在哪些节点上node节点亲和性2在Pod上定义节点亲和规则时有两种类型的节点亲和关系：强制required亲和和首选preferred亲和，或分别称为硬亲和与软亲和。硬亲和：限定调度Pod资源时必须要满足的规则，无可用节点时Pod对象会被置为Pending状态，直到满足规则的节点出现。软亲和：将Pod运行在某类特定的节点之上，但无法满足调度需求时，调度器将选择一个无法匹配规则的节点，而非将Pod置于Pending状态。node节点亲和性2查看node节点亲和性调度字段[root@master1~]#kubectlexplainpods.spec.affinity。。。FIELDS:

nodeAffinity <Object>podAffinity <Object>podAntiAffinity <Object>[root@master1~]#kubectlexplainpods.spec.affinity.nodeAffinity。。。FIELDS:

preferredDuringSchedulingIgnoredDuringExecution <[]Object>

requiredDuringSchedulingIgnoredDuringExecution <Object>node节点亲和性nodeAffinity2软亲和preferredDuringSchedulingIgnoredDuringExecution 硬亲和requiredDuringSchedulingIgnoredDuringExecution 字段名字中的后半段符串IgnoredDuringExecution表示亲和调度仅在调度执行的过程中进行一次即时的判断，而非持续地监视亲和规则是否能够得以满足。node节点亲和性nodeAffinity2查看硬亲和字段[root@master1~]#kubectlexplainpods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution。。。FIELDS:

nodeSelectorTerms <[]Object>-required-Required.Alistofnodeselectorterms.ThetermsareORed.[root@master1~]#kubectlexplainpods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms。。。FIELDS:

matchExpressions <[]Object>#匹配表达式

matchFields <[]Object>#匹配字段node节点亲和性nodeAffinity2matchExpressions：标签选择器表达式，基于节点标签进行过滤；可重复使用以表达不同的匹配条件，各条件间为“或”关系。matchFields：以字段选择器表达的节点选择器；可重复使用以表达不同的匹配条件，各条件间为“或”关系。node节点亲和性nodeAffinity2注意：每个匹配条件可由一到多个匹配规则组成，同一条件下的各条规则彼此间为“逻辑与”关系。这意味着某节点满足nodeSelectorTerms中的任意一个条件即可，但满足某个条件指的是可完全匹配该条件下定义的所有规则。node节点亲和性nodeAffinity2查看matchFields和matchExpressions字段[root@master1~]#kubectlexplainpods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms.matchFields。。。FIELDS:

key <string>-required-

values <[]string>[root@master1~]#kubectlexplainpods.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms.matchExpressions。。。FIELDS:

key <string>-required-#检查label

operator <string>-required-#做等值选则还是不等值选则

values <[]string>#给定值node节点亲和性nodeAffinity2node节点亲和性硬亲和示例使用requiredDuringSchedulingIgnoredDuringExecution硬亲和性把myapp-v1.tar.gz上传到node2和node1上，手动解压：[root@node1~]#dockerload-imyapp-v1.tar.gzLoadedimage:iKubernetes/myapp:v1[root@node2~]#dockerload-imyapp-v1.tar.gzLoadedimage:iKubernetes/myapp:v12node节点亲和性硬亲和示例编辑yaml文件，设置node亲和度[root@master1~]#catpod-nodeaffinity-demo.yaml。。。spec:containers:-name:myappimage:iKubernetes/myapp:v1affinity:nodeAffinity:requiredDuringSchedulingIgnoredDuringExecution:nodeSelectorTerms:-matchExpressions:-key:zoneoperator:Invalues:-foo-bar2node节点亲和性硬亲和示例部署应用检查调度，结果不成功[root@master1~]#kubectlapply-fpod-nodeaffinity-demo.yaml[root@master1~]#kubectlgetpods-owide|greppod-nodepod-node-affinity-demo0/1Pending0node12node节点亲和性硬亲和示例给节点打标签，检查调度，成功[root@master1~]#kubectllabelnodesnode1zone=foo[root@master1~]#kubectlgetpods-owidepod-node-affinity-demo1/1Running0node12node节点亲和性软亲和多个柔性亲和条件并存时，支持为每个条件定义weight属性以区别它们优先级，取值范围是1～100，数字越大优先级越高。2node节点亲和性软亲和示例使用preferredDuringSchedulingIgnoredDuringExecution软亲和性[root@master1~]#catpod-nodeaffini