K8S 高级调度方式
可以使用高级调度分为：
- 节点选择器： nodeSelector、nodeName
- 节点亲和性调度： nodeAffinity
- Pod亲和性调度：PodAffinity
- Pod反亲和性调度：podAntiAffinity
nodeSelector, nodeName
cd; mkdir schedule; cd schedule/
vi pod-demo.yaml
# 内容为
apiVersion: v1
kind: Pod
metadata:
name: pod-demo
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
nodeSelector:
disktype: harddisk
kubectl apply -f pod-demo.yaml
kubectl get pods
kubectl describe pod pod-demo
# 运行结果:
Warning FailedScheduling 2m3s (x25 over 3m15s) default-scheduler 0/3 nodes are available: 3 node(s) didn't match node selector.
# 打上标签
kubectl label node node2 disktype=harddisk
# 正常启动
kubectl get pods
nodeAffinity
requiredDuringSchedulingIgnoredDuringExecution 硬亲和性 必须满足亲和性。
preferredDuringSchedulingIgnoredDuringExecution 软亲和性 能满足最好，不满足也没关系。
硬亲和性：
matchExpressions : 匹配表达式,这个标签可以指定一段，例如pod中定义的key为zone，operator为In(包含那些)，values为 foo和bar。就是在node节点中包含foo和bar的标签中调度
matchFields : 匹配字段 和上面的意思 不过他可以不定义标签值，可以定义
# 选择在 node 有 zone 标签值为 foo 或 bar 值的节点上运行 pod
vi pod-nodeaffinity-demo.yaml
# 内容为
apiVersion: v1
kind: Pod
metadata:
name: pod-node-affinity-demo
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: zone
operator: In
values:
- foo
- bar
kubectl apply -f pod-nodeaffinity-demo.yaml
kubectl describe pod pod-node-affinity-demo
# 运行结果:
Warning FailedScheduling 2s (x8 over 20s) default-scheduler 0/3 nodes are available: 3 node(s) didn't match node selector.
# 给其中一个node打上foo的标签
kubectl label node node1 zone=foo
# 正常启动
kubectl get pods
软亲和性 :
cp pod-nodeaffinity-demo.yaml pod-nodeaffinity-demo-2.yaml
vi pod-nodeaffinity-demo-2.yaml
# 内容为
apiVersion: v1
kind: Pod
metadata:
name: pod-node-affinity-demo-2
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
affinity:
nodeAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- preference:
matchExpressions:
- key: zone
operator: In
values:
- foo
- bar
weight: 60
kubectl apply -f pod-nodeaffinity-demo-2.yaml
podAffinity
Pod亲和性场景，我们的k8s集群的节点分布在不同的区域或者不同的机房，当服务A和服务B要求部署在同一个区域或者同一机房的时候，我们就需要亲和性调度了。
labelSelector : 选择跟那组Pod亲和
namespaces : 选择哪个命名空间
topologyKey : 指定节点上的哪个键
kubectl get pods
kubectl delete pod pod-node-affinity-demo pod-node-affinity-demo-2 pod-demo
cd ~/schedule/
vi pod-required-affinity-demo.yaml
# 内容为：
apiVersion: v1
kind: Pod
metadata:
name: pod-first
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
---
apiVersion: v1
kind: Pod
metadata:
name: pod-second
labels:
app: db
tier: db
spec:
containers:
- name: busybox
image: busybox
imagePullPolicy: IfNotPresent
command: ["sh","-c","sleep 3600"]
affinity:
podAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- {key: app, operator: In, values: ["myapp"]}
topologyKey: kubernetes.io/hostname
kubectl apply -f pod-required-affinity-demo.yaml
kubectl get pods -o wide
# 运行结果，两个 pod 在同一 node 节点上
NAME READY STATUS RESTARTS AGE IP NODE
pod-first 1/1 Running 0 11s 10.244.1.6 node1
pod-second 1/1 Running 0 11s 10.244.1.5 node1
podAntiAffinity
Pod反亲和性场景，当应用服务A和数据库服务B要求尽量不要在同一台节点上的时候。
kubectl delete -f pod-required-affinity-demo.yaml
cp pod-required-affinity-demo.yaml pod-required-anti-affinity-demo.yaml
vi pod-required-anti-affinity-demo.yaml
# 内容为
apiVersion: v1
kind: Pod
metadata:
name: pod-first
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
---
apiVersion: v1
kind: Pod
metadata:
name: pod-second
labels:
app: backend
tier: db
spec:
containers:
- name: busybox
image: busybox:latest
imagePullPolicy: IfNotPresent
command: ["sh","-c","sleep 3600"]
affinity:
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- {key: app, operator: In, values: ["myapp"]}
topologyKey: kubernetes.io/hostname
kubectl apply -f pod-required-anti-affinity-demo.yaml
kubectl get pods -o wide
# 运行结果，两个 pod 不在同一个 node
NAME READY STATUS RESTARTS AGE IP NODE
pod-first 1/1 Running 0 5s 10.244.2.4 node2
pod-second 1/1 Running 0 5s 10.244.1.7 node1
kubectl delete -f pod-required-anti-affinity-demo.yaml
# 如果硬反亲和性定义的标签两个节点都有，则第二个 Pod 没法进行调度，如下面的的 zone=foo
# 给两个 node 打上同一个标签 zone=foo
kubectl label nodes node2 zone=foo
kubectl label nodes node1 zone=foo
vi pod-required-anti-affinity-demo.yaml
# 内容为：
apiVersion: v1
kind: Pod
metadata:
name: pod-first
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
---
apiVersion: v1
kind: Pod
metadata:
name: pod-second
labels:
app: backend
tier: db
spec:
containers:
- name: busybox
image: busybox:latest
imagePullPolicy: IfNotPresent
command: ["sh","-c","sleep 3600"]
affinity:
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- {key: app, operator: In, values: ["myapp"]}
topologyKey: zone
kubectl apply -f pod-required-anti-affinity-demo.yaml
kubectl get pods -o wide
# 结果如下，pod-second 没法启动
NAME READY STATUS RESTARTS AGE IP NODE
pod-first 1/1 Running 0 12s 10.244.1.8 node1
pod-second 0/1 Pending 0 12s <none> <none>
kubectl delete -f pod-required-anti-affinity-demo.yaml
污点容忍调度（Taint和Toleration）
taints and tolerations 允许将某个节点做标记，以使得所有的pod都不会被调度到该节点上。但是如果某个pod明确制定了 tolerates 则可以正常调度到被标记的节点上。
# 可以使用命令行为 Node 节点添加 Taints：
kubectl taint nodes node1 key=value:NoSchedule
operator可以定义为：
Equal：表示key是否等于value，默认
Exists：表示key是否存在，此时无需定义value
tain 的 effect 定义对 Pod 排斥效果:
NoSchedule：仅影响调度过程，对现存的Pod对象不产生影响；
NoExecute：既影响调度过程，也影响显著的Pod对象；不容忍的Pod对象将被驱逐
PreferNoSchedule: 表示尽量不调度
# 查看节点的 taint
kubectl describe node master
kubectl get pods -n kube-system
kubectl describe pods kube-apiserver-master -n kube-system
# 为 node1 打上污点
kubectl taint node node1 node-type=production:NoSchedule
vi deploy-demo.yaml
# 内容为：
apiVersion: apps/v1
kind: Deployment
metadata:
name: myapp-deploy
namespace: default
spec:
replicas: 2
selector:
matchLabels:
app: myapp
release: canary
template:
metadata:
labels:
app: myapp
release: canary
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
ports:
- name: http
containerPort: 80
kubectl apply -f deploy-demo.yaml
kubectl get pods -o wide
# 运行结果：
NAME READY STATUS RESTARTS AGE IP NODE
myapp-deploy-69b47bc96d-cwt79 1/1 Running 0 5s 10.244.2.6 node2
myapp-deploy-69b47bc96d-qqrwq 1/1 Running 0 5s 10.244.2.5 node2
# 为 node2 打上污点
kubectl taint node node2 node-type=dev:NoExecute
# NoExecute 将会驱逐没有容忍该污点的 pod，因两个node节点都有污点，pod没有定义容忍，导致没有节点可以启动pod
kubectl get pods -o wide
# 运行结果：
NAME READY STATUS RESTARTS AGE IP NODE
myapp-deploy-69b47bc96d-psl8f 0/1 Pending 0 14s <none> <none>
myapp-deploy-69b47bc96d-q296k 0/1 Pending 0 14s <none> <none>
# 定义Toleration(容忍)
vi deploy-demo.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: myapp-deploy
namespace: default
spec:
replicas: 2
selector:
matchLabels:
app: myapp
release: canary
template:
metadata:
labels:
app: myapp
release: canary
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v2
ports:
- name: http
containerPort: 80
tolerations:
- key: "node-type"
operator: "Equal"
value: "production"
effect: "NoSchedule"
kubectl apply -f deploy-demo.yaml
# pod 容忍 node1 的 tain ，可以在 node1 上运行
ubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
myapp-deploy-65cc47f858-tmpnz 1/1 Running 0 10s 10.244.1.10 node1
myapp-deploy-65cc47f858-xnklh 1/1 Running 0 13s 10.244.1.9 node1
# 定义Toleration，是否存在 node-type 这个key 且 effect 值为 NoSchedule
vi deploy-demo.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: myapp-deploy
namespace: default
spec:
replicas: 2
selector:
matchLabels:
app: myapp
release: canary
template:
metadata:
labels:
app: myapp
release: canary
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v2
ports:
- name: http
containerPort: 80
tolerations:
- key: "node-type"
operator: "Exists"
value: ""
effect: "NoSchedule"
kubectl apply -f deploy-demo.yaml
kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
myapp-deploy-559f559bcc-6jfqq 1/1 Running 0 10s 10.244.1.11 node1
myapp-deploy-559f559bcc-rlwp2 1/1 Running 0 9s 10.244.1.12 node1
##定义Toleration，是否存在 node-type 这个key 且 effect 值为空，则包含所有的值
vi deploy-demo.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: myapp-deploy
namespace: default
spec:
replicas: 2
selector:
matchLabels:
app: myapp
release: canary
template:
metadata:
labels:
app: myapp
release: canary
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v2
ports:
- name: http
containerPort: 80
tolerations:
- key: "node-type"
operator: "Exists"
value: ""
effect: ""
kubectl apply -f deploy-demo.yaml
# 两个 pod 均衡调度到两个节点
kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE
myapp-deploy-5d9c6985f5-hn4k2 1/1 Running 0 2m 10.244.1.13 node1
myapp-deploy-5d9c6985f5-lkf9q 1/1 Running 0 2m 10.244.2.7 node2
K8S 高级调度方式的更多相关文章
- k8s的高级调度方式
默认的scheduler的调度过程:1.预选策略:从所有节点当中选择基本符合选择条件的节点.2.优选函数:在众多符合基本条件的节点中使用优选函数,计算节点各自的得分,通过比较进行排序.3.从最高得分的 ...
- k8s 高级调度 亲和力和反亲和力、绑定标签、污点容忍污点
通过标签绑定 spec: nodeSelector: bigdata-node: bigdata containers: - env: pod只能运行在有bigdata-node: bigdata 标 ...
- k8s之调度器、预选策略及优选函数
1.调度器(scheduler) 调度器的功能是调度Pod在哪个Node上运行,这些调度信息存储在master上的etcd里面,能够和etcd打交道的只有apiserver; kubelet运行在no ...
- Kubernetes之调度器和调度过程
scheduler 当Scheduler通过API server 的watch接口监听到新建Pod副本的信息后,它会检查所有符合该Pod要求的Node列表,开始执行Pod调度逻辑.调度成功后将Pod绑 ...
- kubernetes集合
kubernetes集合 kubernetes(1):kubernetes简介和组件 kubernetes(2):yum安装kubernetes kubernetes(3):kubeadm安装k8s1 ...
- Linux 系统化学习系列文章总目录（持续更新中）
本页内容都是本人系统化学习Linux 时整理出来的.这些文章中,绝大多数命令类内容都是翻译.整理man或info文档总结出来的,所以相对都比较完整. 本人的写作方式.风格也可能会让朋友一看就恶心到直接 ...
- k8s调度器、预选策略及调度方式
一.k8s调度流程 1.(预选)先排除完全不符合pod运行要求的节点2.(优先)根据一系列算法,算出node的得分,最高没有相同的,就直接选择3.上一步有相同的话,就随机选一个 二.调度方式 1.no ...
- Kubernetes/K8s架构师实战集训营【中、高级班】-2020
下载地址: [中级班] 链接:https://pan.baidu.com/s/1FWAz2V7BPsObixlZyW93sw提取码:mvu0 [高级班] 链接:https://pan.baidu.co ...
- K8S之traefik高级特性
Traefik Traefik是一个用Golang开发的轻量级的Http反向代理和负载均衡器.由于可以自动配置和刷新backend节点,目前可以被绝大部分容器平台支持,例如Kubernetes,Swa ...
随机推荐
- python 77种常用的基础函数
Python: 1. print()函数:打印字符串 2. raw_input()函数:从用户键盘捕获字符 3. len()函数:计算字符长度 4. format(12.3654,’ ...
- 第64节:Java中的Spring Boot 2.0简介笔记
Java中的Spring Boot 2.0简介笔记 spring boot简介 依赖java8的运行环境 多模块项目 打包和运行 spring boot是由spring framework构建的,sp ...
- Kali学习笔记3：TCPDUMP详细使用方法
Kali自带Wireshark,但一般的Linux系统是不带的,需要自行下载,并且过程略复杂 而纯字符界面的Linux系统无法使用Wireshark 但是,所有Linux系统都会安装TCPDUMP:一 ...
- eureka相关异常
1. eureka相关异常 1.1. 异常信息 Error creating bean with name 'eurekaAutoServiceRegistration': Singleton bea ...
- Jdk_API——1.8和Jdk_API1.6下载分享
1.JDK API 1.6 链接:https://pan.baidu.com/s/1bZKfldtqjCOsaYaT1Q9RcQ 提取码:t9ad 2.JDK API 1.8 链接:https ...
- Ansible工具原理一
ansible是新出现的自动化运维工具,基于Python开发,集合了众多运维工具(puppet.cfengine.chef.func.fabric)的优点,实现了批量系统配置.批量程序部署.批量运行命 ...
- git小技巧
1 git提交时如何忽略一些文件: 在git根目录下添加,然后提交,就可以使用了,详细的语法详见 https://github.com/github/gitignore github提供了一个通用的. ...
- Robot Framework - 建立本地测试环境
注意:本文内容是以“在Window7系统中安装本地RobotFrmamework自动化测试环境”为例. Robot Framework简介 HomePage:http://robotframework ...
- 史上最全阿里 Java 面试题总结
以下为大家整理了阿里巴巴史上最全的 Java 面试题,涉及大量 Java 面试知识点和相关试题. JAVA基础 JAVA中的几种基本数据类型是什么,各自占用多少字节. String类能被继承吗,为什么 ...
- leetcode — climbing-stairs
/** * * Source : https://oj.leetcode.com/problems/climbing-stairs/ * * * You are climbing a stair ca ...