文章目录
前言
一：kubectl管理
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kubectl是管理k8s的命令行工具，通过生成json格式传递给apiserver进行一些操作
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更全的kubectl命令请查看
kubectl --help，以下仅列出常用的命令[root@master ~]# kubectl --help kubectl controls the Kubernetes cluster manager. Find more information at: https://kubernetes.io/docs/reference/kubectl/overview/ Basic Commands (Beginner): create Create a resource from a file or from stdin. expose 使用 replication controller, service, deployment 或者 pod 并暴露它作为一个 新的 Kubernetes Service run 在集群中运行一个指定的镜像 set 为 objects 设置一个指定的特征 Basic Commands (Intermediate): explain 查看资源的文档 get 显示一个或更多 resources edit 在服务器上编辑一个资源 delete Delete resources by filenames, stdin, resources and names, or by resources and label selector Deploy Commands: rollout Manage the rollout of a resource scale 为 Deployment, ReplicaSet, Replication Controller 或者 Job 设置一个新的副本数量 autoscale 自动调整一个 Deployment, ReplicaSet, 或者 ReplicationController 的副本数量 Cluster Management Commands: certificate 修改 certificate 资源. cluster-info 显示集群信息 top Display Resource (CPU/Memory/Storage) usage. cordon 标记 node 为 unschedulable uncordon 标记 node 为 schedulable drain Drain node in preparation for maintenance taint 更新一个或者多个 node 上的 taints Troubleshooting and Debugging Commands: describe 显示一个指定 resource 或者 group 的 resources 详情 logs 输出容器在 pod 中的日志 attach Attach 到一个运行中的 container exec 在一个 container 中执行一个命令 port-forward Forward one or more local ports to a pod proxy 运行一个 proxy 到 Kubernetes API server cp 复制 files 和 directories 到 containers 和从容器中复制 files 和 directories. auth Inspect authorization Advanced Commands: apply 通过文件名或标准输入流(stdin)对资源进行配置 patch 使用 strategic merge patch 更新一个资源的 field(s) replace 通过 filename 或者 stdin替换一个资源 wait Experimental: Wait for a specific condition on one or many resources. convert 在不同的 API versions 转换配置文件 Settings Commands: label 更新在这个资源上的 labels annotate 更新一个资源的注解 completion Output shell completion code for the specified shell (bash or zsh) Other Commands: alpha Commands for features in alpha api-resources Print the supported API resources on the server api-versions Print the supported API versions on the server, in the form of "group/version" config 修改 kubeconfig 文件 plugin Provides utilities for interacting with plugins. version 输出 client 和 server 的版本信息 Usage: kubectl [flags] [options] Use "kubectl <command> --help" for more information about a given command. Use "kubectl options" for a list of global command-line options (applies to all commands).
1.1：使用kubectl命令管理项目的生命周期
- 项目的生命周期：创建、发布、更新、回滚、删除
1.1.1：创建
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创建一个nginx的pod
[root@master ~]# kubectl run nginx-test --image=nginx:latest --port=80 --replicas=3 kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead. deployment.apps/nginx-test created [root@master ~]# kubectl get pods -w '//-w：动态查看' [root@master ~]# kubectl get pods -o wide '//查看资源创建在那个节点上' [root@master ~]# kubectl get all '//查看更详细信息：副本资源和控制器资源' [root@master ~]# kubectl get deployment,replicaset '//仅查询pod资源的两个项'
1.1.2、发布
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[root@master ~]# kubectl get svc '//查看原有的service服务' NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 92m [root@master ~]# kubectl expose deployment nginx-test --port=80 --target-port=80 --name=nginx-service --type=NodePort '//将刚刚创建的暴露出来' service/nginx-service exposed [root@master ~]# kubectl get svc '//再次查看' NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 92m nginx-service NodePort 10.0.0.176 <none> 80:36355/TCP 3s [root@master ~]# kubectl get pods -o wide '//查看pods在哪个节点上' NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE nginx-dbddb74b8-5s6h7 1/1 Running 0 7d10h 172.17.26.2 192.168.233.132 <none> nginx-test-59f87d55d6-4rvpl 1/1 Running 0 9m55s 172.17.4.3 192.168.233.133 <none> nginx-test-59f87d55d6-qwrc6 1/1 Running 0 9m55s 172.17.4.2 192.168.233.133 <none> nginx-test-59f87d55d6-xhtpb 1/1 Running 0 9m55s 172.17.26.4 192.168.233.132 <none> [root@master ~]# kubectl get endpoints '//查看pod资源的endpoint' NAME ENDPOINTS AGE kubernetes 192.168.233.130:6443,192.168.233.131:6443 93m nginx-service 172.17.26.4:80,172.17.4.2:80,172.17.4.3:80 38s -
可以查看资源对象的缩写
[root@master dashboard]# kubectl api-resources -
pod资源的调度
当我们创建多个pod、service资源时，kube-proxy会做负载均衡，此时我们通过访问任意node节点ip可以访问所有的资源
kubernetes中kube-proxy支持三种模式，在v1.8之前我们使用的是iptables以及userspace两种模式，在kubernetes1.8之后加入了ipvs
[root@node01 ~]# yum -y install ipvsadm [root@node01 ~]# ipvsadm -L -n '//查看调度' IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddress:Port Scheduler Flags -> RemoteAddress:Port Forward Weight ActiveConn InActConn TCP 127.0.0.1:30005 rr -> 172.17.26.3:8443 Masq 1 0 0 TCP 127.0.0.1:36355 rr '//发现可以访问本地地址可以自动轮询给三个pod资源，node02也是一样的' -> 172.17.4.2:80 Masq 1 0 0 -> 172.17.4.3:80 Masq 1 0 0 -> 172.17.26.4:80 Masq 1 0 0 -
访问网页，查看日志
[root@master ~]# kubectl logs nginx-test-59f87d55d6-4rvpl
[root@master ~]# kubectl logs nginx-test-59f87d55d6-qwrc6
[root@master ~]# kubectl logs nginx-test-59f87d55d6-xhtpb '//网页只访问了一次，所以只有一个pod资源有日志'
...省略内容
172.17.26.1 - - [08/May/2020:04:03:06 +0000] "GET /favicon.ico HTTP/1.1" 404 556 "http://192.168.233.132:36355/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36" "-"
1.1.3：更新
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开发者模式查看版本号（我使用的是谷歌浏览器）
[root@master ~]# kubectl set image deployment/nginx-test nginx-test=nginx:1.13 '//更新版本' deployment.extensions/nginx-test image updated [root@master ~]# kubectl get pods -w '//动态查看' '//容器的更新：滚动更新，容器只有删除和创建，没有重启的' -
重新访问网页，再次查看版本
1.1.4：回滚
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查看历史状态
[root@master ~]# kubectl rollout history deployment/nginx-test deployment.extensions/nginx-test REVISION CHANGE-CAUSE 1 <none> 2 <none> -
执行回滚
[root@master ~]# kubectl rollout undo deployment/nginx-test deployment.extensions/nginx-test [root@master ~]# kubectl get pods -w '//动态查看' -
检查回滚状态
1.1.5：删除
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删除不仅仅是pod，还有service
[root@master ~]# kubectl delete deployment/nginx-test deployment.extensions "nginx-test" deleted [root@master ~]# kubectl get pods -w NAME READY STATUS RESTARTS AGE nginx-dbddb74b8-5s6h7 1/1 Running 0 7d10h nginx-test-59f87d55d6-xgbrd 0/1 Terminating 0 3m13s nginx-test-59f87d55d6-zs5nf 0/1 Terminating 0 2m59s nginx-test-59f87d55d6-zs5nf 0/1 Terminating 0 3m4s nginx-test-59f87d55d6-zs5nf 0/1 Terminating 0 3m4s nginx-test-59f87d55d6-xgbrd 0/1 Terminating 0 3m18s nginx-test-59f87d55d6-xgbrd 0/1 Terminating 0 3m18s ^C[root@master ~]# kubectl get pods '//再次查看pod资源' NAME READY STATUS RESTARTS AGE nginx-dbddb74b8-5s6h7 1/1 Running 0 7d10h [root@master ~]# kubectl get svc '//查看service' NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 137m nginx-service NodePort 10.0.0.176 <none> 80:36355/TCP 44m [root@master ~]# kubectl delete svc/nginx-service '//删除service' service "nginx-service" deleted [root@master ~]# kubectl get svc '//重新查看' NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 137m
1.2：其他常规操作
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查看资源的详细信息
[root@master ~]# kubectl get all NAME READY STATUS RESTARTS AGE pod/nginx-dbddb74b8-5s6h7 1/1 Running 0 7d11h NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE service/kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 163m NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE deployment.apps/nginx 1 1 1 1 7d11h NAME DESIRED CURRENT READY AGE replicaset.apps/nginx-dbddb74b8 1 1 1 7d11h -
查看service资源
[root@master ~]# kubectl describe service/kubernetes Name: kubernetes Namespace: default Labels: component=apiserver provider=kubernetes Annotations: <none> Selector: <none> Type: ClusterIP IP: 10.0.0.1 Port: https 443/TCP TargetPort: 6443/TCP Endpoints: 192.168.233.130:6443,192.168.233.131:6443 Session Affinity: None Events: <none> -
查看deployment资源
[root@master ~]# kubectl describe deployment.apps/nginx Name: nginx Namespace: default CreationTimestamp: Fri, 01 May 2020 01:31:30 +0800 Labels: run=nginx Annotations: deployment.kubernetes.io/revision: 1 Selector: run=nginx Replicas: 1 desired | 1 updated | 1 total | 1 available | 0 unavailable StrategyType: RollingUpdate MinReadySeconds: 0 RollingUpdateStrategy: 25% max unavailable, 25% max surge Pod Template: Labels: run=nginx Containers: nginx: Image: nginx Port: <none> Host Port: <none> Environment: <none> Mounts: <none> Volumes: <none> Conditions: Type Status Reason ---- ------ ------ Available True MinimumReplicasAvailable Progressing True NewReplicaSetAvailable OldReplicaSets: <none> NewReplicaSet: nginx-dbddb74b8 (1/1 replicas created) Events: <none> -
进入pod
[root@master ~]# kubectl exec -it nginx-dbddb74b8-5s6h7 bash root@nginx-dbddb74b8-5s6h7:/# ls bin dev home lib64 mnt proc run srv tmp var boot etc lib media opt root sbin sys usr root@nginx-dbddb74b8-5s6h7:/# exit exit