cloud 07
一、k8s服务管理
创建服务
# 资源清单文件 [root@master ~]# kubectl create service clusterip websvc --tcp=80:80 --dry-run=client -o yaml [root@master ~]# vim websvc.yaml --- kind: Service apiVersion: v1 metadata: name: websvc spec: type: ClusterIP selector: app: web ports: - protocol: TCP port: 80 targetPort: 80 [root@master ~]# kubectl apply -f websvc.yaml service/websvc created [root@master ~]# kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) kubernetes ClusterIP 10.245.0.1 <none> 443/TCP websvc ClusterIP 10.245.5.18 <none> 80/TCP解析域名
# 安装工具软件包 [root@master ~]# dnf install -y bind-utils # 查看 DNS 服务地址 [root@master ~]# kubectl -n kube-system get service kube-dns NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) kube-dns ClusterIP 10.245.0.10 <none> 53/UDP,53/TCP,9153/TCP # 域名解析测试 [root@master ~]# host websvc.default.svc.cluster.local 10.245.0.10 Using domain server: Name: 10.245.0.10 Address: 10.245.0.10#53 Aliases: websvc.default.svc.cluster.local has address 10.245.5.18
创建后端应用
[root@master ~]# vim web1.yaml --- kind: Pod apiVersion: v1 metadata: name: web1 labels: app: web # 服务靠标签寻找后端 spec: containers: - name: apache image: myos:httpd [root@master ~]# kubectl apply -f web1.yaml pod/web1 created [root@master ~]# curl http://10.245.5.18 Welcome to The Apache.负载均衡
[root@master ~]# sed 's,web1,web2,' web1.yaml |kubectl apply -f - pod/web2 created [root@master ~]# sed 's,web1,web3,' web1.yaml |kubectl apply -f - pod/web3 created [root@master ~]# curl -s http://10.245.5.18/info.php |grep php_host php_host: web1 [root@master ~]# curl -s http://10.245.5.18/info.php |grep php_host php_host: web2 [root@master ~]# curl -s http://10.245.5.18/info.php |grep php_host php_host: web3
固定 IP 服务
[root@master ~]# vim websvc.yaml
---
kind: Service
apiVersion: v1
metadata:
name: websvc
spec:
type: ClusterIP
clusterIP: 10.245.1.80 # 可以设置 ClusterIP
selector:
app: web
ports:
- protocol: TCP
port: 80
targetPort: 80
[root@master ~]# kubectl replace --force -f websvc.yaml
service "websvc" deleted
service/websvc replaced
[root@master ~]# kubectl get service
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S)
kubernetes ClusterIP 10.245.0.1 <none> 443/TCP
websvc ClusterIP 10.245.1.80 <none> 80/TCP端口别名
[root@master ~]# vim websvc.yaml --- kind: Service apiVersion: v1 metadata: name: websvc spec: type: ClusterIP clusterIP: 10.245.1.80 selector: app: web ports: - protocol: TCP port: 80 targetPort: myhttp # 使用别名查找后端服务端口 [root@master ~]# kubectl replace --force -f websvc.yaml service "websvc" deleted service/websvc replaced [root@master ~]# kubectl delete pod --all pod "web1" deleted pod "web2" deleted pod "web3" deleted [root@master ~]# vim web1.yaml --- kind: Pod apiVersion: v1 metadata: name: web1 labels: app: web spec: containers: - name: apache image: myos:httpd ports: # 配置端口规范 - name: myhttp # 端口别名 protocol: TCP # 协议 containerPort: 80 # 端口号 [root@master ~]# kubectl apply -f web1.yaml pod/web1 created [root@master ~]# curl http://10.245.1.80 Welcome to The Apache.服务排错
--- kind: Service apiVersion: v1 metadata: name: web123 spec: type: ClusterIP clusterIP: 192.168.1.88 selector: app: apache ports: - protocol: TCP port: 80 targetPort: webnodePort
对外发布服务
[root@master ~]# vim mysvc.yaml --- kind: Service apiVersion: v1 metadata: name: mysvc spec: type: NodePort # 服务类型 selector: app: web ports: - protocol: TCP port: 80 nodePort: 30080 # 映射端口号 targetPort: 80 [root@master ~]# kubectl apply -f mysvc.yaml service/mysvc configured [root@master ~]# kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) kubernetes ClusterIP 10.245.0.1 <none> 443/TCP websvc ClusterIP 10.245.1.80 <none> 80/TCP mysvc NodePort 10.245.3.88 <none> 80:30080/TCP [root@master ~]# curl http://node-0001:30080 Welcome to The Apache. [root@master ~]# curl http://node-0002:30080 Welcome to The Apache. [root@master ~]# curl http://node-0003:30080 Welcome to The Apache. [root@master ~]# curl http://node-0004:30080 Welcome to The Apache. [root@master ~]# curl http://node-0005:30080 Welcome to The Apache.二、lngress 安装与策略配置
安装控制器
[root@master ~]# cd plugins/ingress [root@master ingress]# docker load -i ingress.tar.xz [root@master ingress]# docker images|while read i t _;do [[ "${t}" == "TAG" ]] && continue [[ "${i}" =~ ^"harbor:443/".+ ]] && continue docker tag ${i}:${t} harbor:443/plugins/${i##*/}:${t} docker push harbor:443/plugins/${i##*/}:${t} docker rmi ${i}:${t} harbor:443/plugins/${i##*/}:${t} done [root@master ingress]# sed -ri 's,^(\s*image: )(.*/)?(.+),\1harbor:443/plugins/\3,' deploy.yaml 443: image: registry.k8s.io/ingress-nginx/controller:v1.9.6 546: image: registry.k8s.io/ingress-nginx/kube-webhook-certgen:v20231226-1a7112e06 599: image: registry.k8s.io/ingress-nginx/kube-webhook-certgen:v20231226-1a7112e06 [root@master ingress]# kubectl apply -f deploy.yaml [root@master ingress]# kubectl -n ingress-nginx get pods NAME READY STATUS RESTARTS ingress-nginx-admission-create--1-lm52c 0/1 Completed 0 ingress-nginx-admission-patch--1-sj2lz 0/1 Completed 0 ingress-nginx-controller-5664857866-tql24 1/1 Running 0验证后端服务
[root@master ~]# kubectl get pods,services NAME READY STATUS RESTARTS AGE pod/web1 1/1 Running 0 35m NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) service/kubernetes ClusterIP 10.245.0.1 <none> 443/TCP service/websvc ClusterIP 10.245.1.80 <none> 80/TCP service/mysvc NodePort 10.245.3.88 <none> 80:30080/TCP [root@master ~]# curl http://10.245.1.80 Welcome to The Apache.对外发布服务
# 查询 ingress 控制器类名称 [root@master ~]# kubectl get ingressclasses.networking.k8s.io NAME CONTROLLER PARAMETERS AGE nginx k8s.io/ingress-nginx <none> 5m7s # 资源清单文件 [root@master ~]# kubectl create ingress mying --class=nginx --rule=nsd.tedu.cn/*=mysvc:80 --dry-run=client -o yaml [root@master ~]# vim mying.yaml --- kind: Ingress apiVersion: networking.k8s.io/v1 metadata: name: mying spec: ingressClassName: nginx rules: - host: nsd.tedu.cn http: paths: - path: / pathType: Prefix backend: service: name: websvc port: number: 80 [root@master ~]# kubectl apply -f mying.yaml ingress.networking.k8s.io/mying created [root@master ~]# kubectl get ingress NAME CLASS HOSTS ADDRESS PORTS mying nginx nsd.tedu.cn 192.168.1.51 80 [root@master ~]# curl -H "Host: nsd.tedu.cn" http://192.168.1.51 Welcome to The Apache.
三、Dashboard 安装
#下面给大家介绍下新的k8s插件
web 管理插件
安装 Dashboard
[root@master ~]# cd plugins/dashboard [root@master dashboard]# docker load -i dashboard.tar.xz [root@master dashboard]# docker images|while read i t _;do [[ "${t}" == "TAG" ]] && continue [[ "${i}" =~ ^"harbor:443/".+ ]] && continue docker tag ${i}:${t} harbor:443/plugins/${i##*/}:${t} docker push harbor:443/plugins/${i##*/}:${t} docker rmi ${i}:${t} harbor:443/plugins/${i##*/}:${t} done [root@master dashboard]# sed -ri 's,^(\s*image: )(.*/)?(.+),\1harbor:443/plugins/\3,' recommended.yaml 193: image: kubernetesui/dashboard:v2.7.0 278: image: kubernetesui/metrics-scraper:v1.0.8 [root@master dashboard]# kubectl apply -f recommended.yaml [root@master dashboard]# kubectl -n kubernetes-dashboard get pods NAME READY STATUS RESTARTS dashboard-metrics-scraper-66f6f56b59-b42ng 1/1 Running 0 kubernetes-dashboard-65ff57f4cf-lwtsk 1/1 Running 0发布服务
# 查看服务状态 [root@master dashboard]# kubectl -n kubernetes-dashboard get service NAME TYPE CLUSTER-IP PORT(S) dashboard-metrics-scraper ClusterIP 10.245.205.236 8000/TCP kubernetes-dashboard ClusterIP 10.245.215.40 443/TCP # 获取服务资源对象文件 [root@master dashboard]# sed -n '30,45p' recommended.yaml >dashboard-svc.yaml [root@master dashboard]# vim dashboard-svc.yaml --- kind: Service apiVersion: v1 metadata: labels: k8s-app: kubernetes-dashboard name: kubernetes-dashboard namespace: kubernetes-dashboard spec: type: NodePort ports: - port: 443 nodePort: 30443 targetPort: 8443 selector: k8s-app: kubernetes-dashboard [root@master dashboard]# kubectl apply -f dashboard-svc.yaml service/kubernetes-dashboard configured [root@master dashboard]# kubectl -n kubernetes-dashboard get service NAME TYPE CLUSTER-IP PORT(S) dashboard-metrics-scraper ClusterIP 10.245.205.236 8000/TCP kubernetes-dashboard NodePort 10.245.215.40 443:30443/TCP
- #记得访问下仪表盘dashboard登录页面
四、RBAC 权限管理
服务账号与权限
创建服务账号
# 资源对象模板 [root@master ~]# kubectl -n kubernetes-dashboard create serviceaccount kube-admin --dry-run=client -o yaml [root@master ~]# vim admin-user.yaml --- kind: ServiceAccount apiVersion: v1 metadata: name: kube-admin namespace: kubernetes-dashboard [root@master ~]# kubectl apply -f admin-user.yaml serviceaccount/kube-admin created [root@master ~]# kubectl -n kubernetes-dashboard get serviceaccounts NAME SECRETS AGE default 0 16m kube-admin 0 11s kubernetes-dashboard 0 16m获取用户 token
[root@master ~]# kubectl -n kubernetes-dashboard create token kube-admin <Base64 编码的令牌数据>
角色与鉴权
#类似网游DNF里面的角色管理，GM管理员和玩家的关系。
资源对象 描述 作用域 ServiceAccount 服务账号，为 Pod 中运行的进程提供了一个身份 单一名称空间 Role 角色，包含一组代表相关权限的规则 单一名称空间 ClusterRole 角色，包含一组代表相关权限的规则 全集群 RoleBinding 将权限赋予用户，Role、ClusterRole 均可使用 单一名称空间 ClusterRoleBinding 将权限赋予用户，只可以使用 ClusterRole 全集群 资源对象权限
create delete deletecollection get list patch update watch 创建 删除 删除集合 获取属性 获取列表 补丁 更新 监控 普通角色
[root@master ~]# kubectl cluster-info dump |grep authorization-mode "--authorization-mode=Node,RBAC", # 资源对象模板 [root@master ~]# kubectl -n default create role myrole --resource=pods --verb=get,list --dry-run=client -o yaml [root@master ~]# kubectl -n default create rolebinding kube-admin-role --role=myrole --serviceaccount=kubernetes-dashboard:kube-admin --dry-run=client -o yaml [root@master ~]# vim myrole.yaml --- kind: Role apiVersion: rbac.authorization.k8s.io/v1 metadata: name: myrole namespace: default rules: - apiGroups: - "" resources: - pods verbs: - get - list --- kind: RoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: kube-admin-role namespace: default roleRef: apiGroup: rbac.authorization.k8s.io kind: Role name: myrole subjects: - kind: ServiceAccount name: kube-admin namespace: kubernetes-dashboard [root@master ~]# kubectl apply -f myrole.yaml role.rbac.authorization.k8s.io/myrole created rolebinding.rbac.authorization.k8s.io/kube-admin-role created [root@master ~]# kubectl delete -f myrole.yaml role.rbac.authorization.k8s.io "myrole" deleted rolebinding.rbac.authorization.k8s.io "kube-admin-role" deleted集群管理员
[root@master ~]# kubectl get clusterrole NAME CREATED AT admin 2022-06-24T08:11:17Z cluster-admin 2022-06-24T08:11:17Z ... ... # 资源对象模板 [root@master ~]# kubectl create clusterrolebinding kube-admin-role --clusterrole=cluster-admin --serviceaccount=kubernetes-dashboard:kube-admin --dry-run=client -o yaml [root@master ~]# vim admin-user.yaml --- kind: ServiceAccount apiVersion: v1 metadata: name: kube-admin namespace: kubernetes-dashboard --- kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: kube-admin-role roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: cluster-admin subjects: - kind: ServiceAccount name: kube-admin namespace: kubernetes-dashboard [root@master ~]# kubectl apply -f admin-user.yaml serviceaccount/kube-admin unchanged clusterrolebinding.rbac.authorization.k8s.io/kube-admin-role created
cloud 08
#上一小节讲过K8S的有控制组件和计算组件。现在我们一起来深入研究K8S的控制组件。
一、Deployment
资源清单文件
[root@master ~]# kubectl create deployment myweb --image=myos:httpd --dry-run=client -o yaml
[root@master ~]# vim mydeploy.yaml
---
kind: Deployment # 资源对象类型
apiVersion: apps/v1 # 版本
metadata: # 元数据
name: mydeploy # 名称
spec: # 详细定义
replicas: 3 # 副本数量
selector: # 定义标签选择器
matchLabels: # 支持 matchExpressions 表达式语法
app: deploy-httpd # 通过标签来确定那个 Pod 由它来管理
template: # 定义用来创建 Pod 的模板,以下为 Pod 定义
metadata:
labels:
app: deploy-httpd
spec:
containers:
- name: apache
image: myos:httpd
配置案例
# 创建控制器
[root@master ~]# kubectl apply -f mydeploy.yaml
deployment.apps/mydeploy created
[root@master ~]# kubectl get deployments
NAME READY UP-TO-DATE AVAILABLE AGE
mydeploy 3/3 3 3 1s
# 控制器自动创建 ReplicaSet
[root@master ~]# kubectl get replicasets
NAME DESIRED CURRENT READY AGE
mydeploy-76f96b85df 3 3 3 2s
# 控制器自动创建 Pod
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
mydeploy-76f96b85df-5gng9 1/1 Running 0 3s
mydeploy-76f96b85df-vsfrw 1/1 Running 0 3s
mydeploy-76f96b85df-z9x95 1/1 Running 0 3s
# 集群自维护自治理
[root@master ~]# kubectl delete pod --all
pod "mydeploy-76f96b85df-5gng9" deleted
pod "mydeploy-76f96b85df-vsfrw" deleted
pod "mydeploy-76f96b85df-z9x95" deleted
# 删除后自动重新创建
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
mydeploy-76f96b85df-7dvwh 1/1 Running 0 7s
mydeploy-76f96b85df-kpbz4 1/1 Running 0 7s
mydeploy-76f96b85df-kr2zq 1/1 Running 0 7s集群服务
# 创建集群服务 [root@master ~]# vim websvc.yaml --- kind: Service apiVersion: v1 metadata: name: websvc spec: type: ClusterIP clusterIP: 10.245.1.80 selector: app: deploy-httpd ports: - protocol: TCP port: 80 targetPort: 80 [root@master ~]# kubectl replace --force -f websvc.yaml service/websvc replaced [root@master ~]# curl -m 3 http://10.245.1.80 Welcome to The Apache.集群扩缩容
#抽象来说，扩容就是在基础存储设备上，添加新的设备，然后挂载到新的设备上。达到扩容结果， 类似吃鸡游戏里的扩容弹夹。
而缩容就是为了达到更佳的运行效率，减少存储设备上的存储空间，达到缩容目的。古代的增兵减灶
# 集群扩容 [root@master ~]# kubectl scale deployment mydeploy --replicas 10 deployment.apps/mydeploy scaled [root@master ~]# kubectl get pods NAME READY STATUS RESTARTS AGE mydeploy-76f96b85df-kg27l 1/1 Running 0 6s mydeploy-76f96b85df-q5fzb 1/1 Running 0 6s mydeploy-76f96b85df-rxhp4 1/1 Running 0 6s mydeploy-76f96b85df-szf69 1/1 Running 0 6s mydeploy-76f96b85df-tp2xj 1/1 Running 0 6s ...... # 集群缩容 [root@master ~]# kubectl scale deployment mydeploy --replicas=2 deployment.apps/mydeploy scaled [root@master ~]# kubectl get pods NAME READY STATUS RESTARTS AGE mydeploy-76f96b85df-7dvwh 1/1 Running 0 51s mydeploy-76f96b85df-kr2zq 1/1 Running 0 51s历史版本信息
# 查看历史版本 [root@master ~]# kubectl rollout history deployment mydeploy deployment.apps/mydeploy REVISION CHANGE-CAUSE 1 <none> # 添加注释信息 [root@master ~]# kubectl annotate deployments mydeploy kubernetes.io/change-cause="httpd.v1" deployment.apps/mydeploy annotated [root@master ~]# kubectl rollout history deployment mydeploy deployment.apps/mydeploy REVISION CHANGE-CAUSE 1 httpd.v1 # 更新资源清单文件 [root@master ~]# vim mydeploy.yaml # 在创建容器的镜像下面添加 imagePullPolicy: Always [root@master ~]# kubectl apply -f mydeploy.yaml deployment.apps/mydeploy patched # 更新版本信息 [root@master ~]# kubectl annotate deployments mydeploy kubernetes.io/change-cause="httpd.v2" deployment.apps/mydeploy annotated [root@master ~]# kubectl rollout history deployment mydeploy deployment.apps/mydeploy REVISION CHANGE-CAUSE 1 httpd.v1 2 httpd.v2滚动更新
# 修改镜像，滚动更新集群 [root@master ~]# kubectl set image deployment mydeploy apache=myos:nginx deployment.apps/mydeploy image updated # 给新版本添加注释信息 [root@master ~]# kubectl annotate deployments mydeploy kubernetes.io/change-cause="nginx.v1" deployment.apps/mydeploy annotated # 查看历史版本信息 [root@master ~]# kubectl rollout history deployment mydeploy deployment.apps/mydeploy REVISION CHANGE-CAUSE 1 httpd.v1 2 httpd.v2 3 nginx.v1 # 访问验证服务 [root@master ~]# curl -m 3 http://10.245.1.80 Nginx is running !版本回滚
#类似游戏里面的怀旧服，而这里的版本回滚是用于恢复数据
# 历史版本与回滚 [root@master ~]# kubectl rollout undo deployment mydeploy --to-revision 1 deployment.apps/mydeploy rolled back [root@master ~]# kubectl rollout history deployment mydeploy deployment.apps/mydeploy REVISION CHANGE-CAUSE 2 httpd.v2 3 nginx.v1 4 httpd.v1 [root@master ~]# curl -m 3 http://10.245.1.80 Welcome to The Apache.
清理资源对象
# 删除控制器时会自动回收自己创建的 Pod
[root@master ~]# kubectl delete deployments mydeploy
deployment.apps "mydeploy" deleted二、DaemonSet
配置案例
[root@master ~]# cp -a mydeploy.yaml myds.yaml [root@master ~]# vim myds.yaml --- kind: DaemonSet # 资源对象类型 apiVersion: apps/v1 metadata: name: myds # 控制器名称 spec: # replicas: 2 # 删除副本参数 selector: matchLabels: app: ds-httpd # 修改标签防止冲突 template: metadata: labels: app: ds-httpd # 修改标签防止冲突 spec: containers: - name: apache image: myos:httpd imagePullPolicy: Always [root@master ~]# kubectl apply -f myds.yaml daemonset.apps/myds created [root@master ~]# kubectl get pods -o wide NAME READY STATUS RESTARTS IP NODE myds-msrcx 1/1 Running 0 10.244.1.11 node-0001 myds-lwq8l 1/1 Running 0 10.244.2.17 node-0002 myds-4wt72 1/1 Running 0 10.244.3.14 node-0003 myds-6k82t 1/1 Running 0 10.244.4.15 node-0004 myds-9c6wc 1/1 Running 0 10.244.5.19 node-0005
清理资源对象
# 删除控制器
[root@master ~]# kubectl delete daemonsets myds
daemonset.apps "myds" deleted三、Job、CronJob
Job 控制器
# 资源文件模板
[root@master ~]# kubectl create job myjob --image=myos:8.5 --dry-run=client -o yaml -- sleep 3
[root@master ~]# vim myjob.yaml
---
kind: Job
apiVersion: batch/v1
metadata:
name: myjob
spec:
template: # 以下定义 Pod 模板
metadata: {}
spec:
restartPolicy: OnFailure
containers:
- name: myjob
image: myos:8.5
command: ["/bin/sh"]
args:
- -c
- |
sleep 3
exit $((RANDOM%2))
[root@master ~]# kubectl apply -f myjob.yaml
job.batch/myjob created
# 失败了会重启
[root@master ~]# kubectl get pods -l job-name=myjob -w
NAME READY STATUS RESTARTS AGE
myjob--1-lrtbk 1/1 Running 0 2s
myjob--1-lrtbk 0/1 Error 0 4s
myjob--1-lrtbk 1/1 Running 1 (1s ago) 5s
myjob--1-lrtbk 0/1 Completed 1 9s
[root@master ~]# kubectl get jobs.batch
NAME COMPLETIONS DURATION AGE
myjob 1/1 8s 12s
# 删除Job控制器
[root@master ~]# kubectl delete -f myjob.yaml
job.batch "myjob" deleted#pod控制器创建失败，任务会确保创建成功而重启，避免失败
Cronjob
#类似ansible中的crontab模块，可以定时执行某一任务
配置案例
# 资源对象模板 [root@master ~]# kubectl create cronjob mycj --image=myos:8.5 --schedule='* * * * *' --dry-run=client -o yaml -- sleep 3 [root@master ~]# vim mycj.yaml --- kind: CronJob apiVersion: batch/v1 metadata: name: mycj spec: schedule: "* * * * *" jobTemplate: # 以下定义 Job 模板 metadata: {} spec: template: metadata: {} spec: restartPolicy: OnFailure containers: - name: myjob image: myos:8.5 command: ["/bin/sh"] args: - -c - | sleep 3 exit $((RANDOM%2)) [root@master ~]# kubectl apply -f mycj.yaml cronjob.batch/mycj created [root@master ~]# kubectl get cronjobs NAME SCHEDULE SUSPEND ACTIVE LAST SCHEDULE AGE mycj * * * * 1-5 False 0 <none> 4s # 按照时间周期，每分钟触发一个任务 [root@master ~]# kubectl get jobs -w NAME READY STATUS RESTARTS mycj-27808172--1-w6sbx 0/1 Pending 0 mycj-27808172--1-w6sbx 0/1 ContainerCreating 0 mycj-27808172--1-w6sbx 1/1 Running 0 mycj-27808172--1-w6sbx 0/1 Completed 1 # 保留三次结果，多余的会被删除 [root@master ~]# kubectl get jobs NAME COMPLETIONS DURATION AGE mycj-27605367 1/1 31s 3m30s mycj-27605368 1/1 31s 2m30s mycj-27605369 1/1 31s 90s mycj-27605370 0/1 30s 30s [root@master ~]# kubectl get jobs NAME COMPLETIONS DURATION AGE mycj-27605368 1/1 31s 2m33s mycj-27605369 1/1 31s 93s mycj-27605370 1/1 31s 33s # 删除CJ控制器 [root@master ~]# kubectl delete -f mycj.yaml cronjob.batch "mycj" deleted
四、StatefulSet
Headless 服务
[root@master ~]# cp websvc.yaml stssvc.yaml [root@master ~]# vim stssvc.yaml --- kind: Service apiVersion: v1 metadata: name: stssvc # 服务名称 spec: type: ClusterIP clusterIP: None # 设置 IP 为 None selector: app: sts-httpd # 设置 Pod 标签 ports: - protocol: TCP port: 80 targetPort: 80 [root@master ~]# kubectl apply -f stssvc.yaml service/stssvc created [root@master ~]# kubectl get services stssvc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE stssvc ClusterIP None <none> 80/TCP 51s资源清单文件
[root@master ~]# cp -a mydeploy.yaml mysts.yaml [root@master ~]# vim mysts.yaml --- kind: StatefulSet # 资源对象类型 apiVersion: apps/v1 metadata: name: mysts # 控制器名称 spec: serviceName: stssvc # 新增 headless 服务名称 replicas: 3 selector: matchLabels: app: sts-httpd # 修改标签防止冲突 template: metadata: labels: app: sts-httpd # 修改标签防止冲突 spec: containers: - name: apache image: myos:httpd配置案例
# statefulset 主要解决了 Pod 创建顺序的问题 # statefulset 主要解决了访问指定 Pod 的问题 [root@master ~]# kubectl apply -f mysts.yaml statefulset.apps/mysts created [root@master ~]# kubectl get pods NAME READY STATUS RESTARTS AGE mysts-0 1/1 Running 0 3s mysts-1 1/1 Running 0 2s mysts-2 1/1 Running 0 1s # 所有 Pod IP 地址 [root@master ~]# host stssvc.default.svc.cluster.local 10.245.0.10 Using domain server: Name: 10.245.0.10 Address: 10.245.0.10#53 Aliases: stssvc.default.svc.cluster.local has address 10.244.1.81 stssvc.default.svc.cluster.local has address 10.244.2.82 stssvc.default.svc.cluster.local has address 10.244.3.83 # 单个 Pod IP 地址 [root@master ~]# host mysts-0.stssvc.default.svc.cluster.local 10.245.0.10 Using domain server: Name: 10.245.0.10 Address: 10.245.0.10#53 Aliases: mysts-0.stssvc.default.svc.cluster.local has address 10.244.1.81 # 删除sts控制器 [root@master ~]# kubectl delete -f mysts.yaml -f stssvc.yaml statefulset.apps "mysts" deleted service "stssvc" deleted 弹性云服务五、HorizontalPodAutoscaler
配置后端服务
# 为 Deploy 模板添加资源配额
[root@master ~]# cat mydeploy.yaml websvc.yaml >mycluster.yaml
[root@master ~]# vim mycluster.yaml
---
kind: Deployment
apiVersion: apps/v1
metadata:
name: mydeploy
spec:
replicas: 1
selector:
matchLabels:
app: deploy-httpd
template:
metadata:
labels:
app: deploy-httpd
spec:
containers:
- name: apache
image: myos:httpd
resources: # 为该资源设置配额
requests: # HPA 控制器会根据配额使用情况伸缩集群
cpu: 300m # CPU 配额
---
kind: Service
apiVersion: v1
metadata:
name: websvc
spec:
type: ClusterIP
clusterIP: 10.245.1.80
selector:
app: deploy-httpd
ports:
- protocol: TCP
port: 80
targetPort: 80
[root@master ~]# kubectl replace --force -f mycluster.yaml
deployment.apps/mydeploy replaced
service/websvc replaced
# 验证服务
[root@master ~]# kubectl top pods
NAME CPU(cores) MEMORY(bytes)
mydeploy-b4f9dc786-w4x2z 6m 18Mi
[root@master ~]# curl -s http://10.245.1.80/info.php
<pre>
Array
(
[REMOTE_ADDR] => 10.244.219.64
[REQUEST_METHOD] => GET
[HTTP_USER_AGENT] => curl/7.61.1
[REQUEST_URI] => /info.php
)
php_host: mydeploy-b4f9dc786-w4x2z
1229HPA 控制器
[root@master ~]# vim myhpa.yaml --- kind: HorizontalPodAutoscaler apiVersion: autoscaling/v2 metadata: name: myhpa spec: behavior: scaleDown: stabilizationWindowSeconds: 60 scaleTargetRef: kind: Deployment apiVersion: apps/v1 name: mydeploy minReplicas: 1 maxReplicas: 5 metrics: - type: Resource resource: name: cpu target: type: Utilization averageUtilization: 50 [root@master ~]# kubectl apply -f myhpa.yaml horizontalpodautoscaler.autoscaling/myhpa created # 刚刚创建 unknown 是正常现象，最多等待 60s 就可以正常获取数据 [root@master ~]# kubectl get horizontalpodautoscalers NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS myhpa Deployment/mydeploy <unknown>/50% 1 5 0 [root@master ~]# kubectl get horizontalpodautoscalers NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS myhpa Deployment/mydeploy 0%/50% 1 5 3配置案例
# 终端 1 访问提高负载 [root@master ~]# while sleep 1;do curl -s "http://10.245.1.80/info.php?id=100000" -o /dev/null; done & # 终端 2 监控 HPA 变化 [root@master ~]# kubectl get hpa -w NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE myhpa Deployment/mydeploy 0%/50% 1 5 1 1m myhpa Deployment/mydeploy 31%/50% 1 5 1 2m myhpa Deployment/mydeploy 70%/50% 1 5 1 2m15s myhpa Deployment/mydeploy 72%/50% 1 5 2 2m30s myhpa Deployment/mydeploy 36%/50% 1 5 2 2m45s myhpa Deployment/mydeploy 55%/50% 1 5 2 3m myhpa Deployment/mydeploy 58%/50% 1 5 3 3m15s myhpa Deployment/mydeploy 39%/50% 1 5 3 3m30s ... ... myhpa Deployment/mydeploy 66%/50% 1 5 4 5m myhpa Deployment/mydeploy 68%/50% 1 5 5 5m15s myhpa Deployment/mydeploy 55%/50% 1 5 5 5m30s myhpa Deployment/mydeploy 58%/50% 1 5 5 5m45s myhpa Deployment/mydeploy 62%/50% 1 5 5 6m # 如果 60s 内平均负载小于标准值，就会自动缩减集群规模 [root@master ~]# kubectl get hpa -w NAME REFERENCE TARGETS MINPODS MAXPODS REPLICAS AGE myhpa Deployment/mydeploy 52%/50% 1 5 5 13m myhpa Deployment/mydeploy 44%/50% 1 5 5 13m15s myhpa Deployment/mydeploy 38%/50% 1 5 5 13m30s myhpa Deployment/mydeploy 35%/50% 1 5 5 13m45s myhpa Deployment/mydeploy 28%/50% 1 5 5 14m ... ... myhpa Deployment/mydeploy 8%/50% 1 5 5 18m30s myhpa Deployment/mydeploy 9%/50% 1 5 4 18m45s myhpa Deployment/mydeploy 9%/50% 1 5 4 19m myhpa Deployment/mydeploy 12%/50% 1 5 3 19m15s myhpa Deployment/mydeploy 15%/50% 1 5 3 19m30s myhpa Deployment/mydeploy 18%/50% 1 5 2 19m45s myhpa Deployment/mydeploy 33%/50% 1 5 1 20m
课后总结:
#我们本节学的好多控制器，都有差异和区别，可以按照类似以下的提示词，来对AI提问，得到更加符合工作使用环境的回答。
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