a.用户期望的pod副本数量; b.标签选择器,判断哪个pod归自己管理; c.pod资源模板,当现存的pod数量不足,会根据pod资源模板进行新建.
cat rs-demo.yaml apiVersion: apps/v1 kind: ReplicaSet metadata: name: rs-myapp namespace: default spec: replicas: 2 selector: matchLabels: run: myapp release: canary template: metadata: name: whatever labels: run: myapp release: canary env: test spec: containers: - name: nginx-web image: ikubernetes/myapp:v1 ports: - name: http containerPort: 80 template:资源模板中定义的name其实不生效,pod运行起来之后,真正的名字是控制器名+随机字符串 kubectl create -f rs-demo.yaml kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE rs-myapp-2hxc9 1/1 Running 0 74s 10.244.2.7 k8s-node2 rs-myapp-d6845 1/1 Running 0 74s 10.244.1.9 k8s-node1 curl 10.244.2.7 Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a> # 编辑replicatset的配置文件,这个文件不是我们手工创建的,而是apiserver维护的,修改副本数 kubectl edit rs myapp # 也可以升级版本,将v1改成v2,但只有pod重建后,比如增加或删除Pod,才会更新成v2版本
kubectl explain deploy # 文档是落后于k8s版本的 deploy示例: cat 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:v1 ports: - name: http containerPort: 80 # apply:声明式更新和创建,可以应用多次,create只能用一次 kubectl apply -f deploy-demo.yaml kubectl get deploy # 会看见一个名为myapp-deploy的deploy生成 kubectl get rs NAME DESIRED CURRENT READY AGE myapp-deploy-574965d786 2 2 2 93s kubectl get pods NAME READY STATUS RESTARTS AGE myapp-deploy-574965d786-5x42g 1/1 Running 0 70s myapp-deploy-574965d786-dqzpd 1/1 Running 0 70s # 默认滚动策略是RollingUpdate,查看滚动更新的历史 kubectl rollout history deployment myapp-deploy # 如果要修改副本数,则编辑deploy-demo.yaml修改副本数,或者: kubectl patch deployment myapp-deploy -p '{"spec":{"replicas":5}}' # 给更新策略打补丁: kubectl patch deployment myapp-deploy -p '{"spec":{"strategy":{"rollingUpdate":{"maxSurge":1,"maxUnavailable":0}}}}' # maxSurge:pod的数量最多可超出期望值多少个;maxUnavailable:最多不可用的pod有多少个. # 金丝雀发布,先发布一个,此时多了一个pod,现在有6个 # 用set image命令将镜像myapp升级为v3版本,并且将myapp-deploy控制器标记为暂停, # 被暂停的资源不会被控制器使用,可以使"kubectl rollout resume"命令恢复已暂停资源 kubectl set image deployment myapp-deploy myapp=ikubernetes/myapp:v3 && kubectl rollout pause deployment myapp-deploy kubectl get pods -l app=myapp -w # resume:继续,重新开始,可以看到继续更新,删一个更新一个 kubectl rollout status deployment myapp-deploy kubectl rollout resume deployment myapp-deploy # 查看副本集的详细信息 kubectl get rs -o wide # 版本回滚 kubectl rollout history deployment myapp-deploy kubectl rollout undo deployment myapp-deploy --to-revision=1 # node1、node2下载filebeat镜像 docker pull ikubernetes/filebeat:5.6.5-alpine cat ds-demo.yaml apiVersion: apps/v1 kind: Deployment metadata: name: redis namespace: default spec: replicas: 1 selector: matchLabels: app: redis role: logstor template: metadata: labels: app: redis role: logstor spec: containers: - name: redis image: redis:4.0-alpine ports: - name: redis containerPort: 6379 --- # 减号隔离不同资源定义 apiVersion: apps/v1 kind: DaemonSet metadata: name: filebeat-ds namespace: default spec: selector: matchLabels: app: filebeat release: stable template: metadata: labels: app: filebeat release: stable spec: containers: - name: filebeat image: ikubernetes/filebeat:5.6.5-alpine env: - name: REDIS_HOST value: redis.default.svc.cluster.local - name: REDIS_LOG_LEVEL value: info # REDIS_HOST这个键值对是filebeat-ds向filebeat配置文件传的环境变量 kubectl apply -f ds-demo.yaml # 暴露redis端口 kubectl expose deployment redis --port=6379 # 进入redis kubectl exec -it redis-664bbc646b-sg6wk -- /bin/sh /data # redis-cli -h redis.default.svc.cluster.local # 进入filebeat kubectl exec -it filebeat-ds-bszfz -- /bin/sh nslookup redis.default.svc.cluster.local # daemon-set也支持滚动更新 kubectl set image daemonsets filebeat-ds filebeat=ikubernetes/filebeat:5.5.7-alpine kubectl explain pods.spec # 有一个字段hostNetwork,可以让容器直接共享宿主机的网络 注:不同pod之间通信,filebeat向redis发送日志靠的是service
