实战入门POD

　　pod是k8s中最小的管理单元，程序在容器中，容器在pod中
　　k8s通过管理pod来管理容器，通过管理容器进而管理程序
　　pod可以说是容器的封装，一个pod中可以存在一个或多个容器 [qq@k8snode1 ~]$ kubectl get pods -n kube-system NAME                               READY   STATUS    RESTARTS      AGE coredns-64897985d-bnkbc            1/1     Running   0             45s etcd-minikube                      1/1     Running   1             57s kube-apiserver-minikube            1/1     Running   2             57s kube-controller-manager-minikube   1/1     Running   1             58s kube-proxy-tgbx2                   1/1     Running   0             45s kube-scheduler-minikube            1/1     Running   1             57s storage-provisioner                1/1     Running   2 (40s ago)   54s   APIservice 所有服务的访问统一入口 crontrollerManager：维持副本期望数目 Scheduler：负责介绍任务，选择合适的节点进行分配任务 ETCD：键值对数据库 存储K8s集群所有重要信息持久化，负责存储集群中各种资源对象的信息 Kubelet：直接跟容器引擎交互实现容器的生命周期管理 Kube-proxy：负责写入规则至IPTABLES，IPVS实现服务映射访问 docker：节点上的容器操作  [qq@k8snode1 ~]$ kubectl create ns dev namespace/dev created  《创建命名空间》 [qq@k8snode1 ~]$ kubectl get ns NAME              STATUS   AGE default           Active   7m54s dev               Active   10s kube-node-lease   Active   7m55s kube-public       Active   7m55s kube-system       Active   7m55s 《看一下》 [qq@k8snode1 ~]$  kubectl  run nginxss --image=nginx:1.17.1 --port=80 -n dev pod/nginxss created [qq@k8snode1 ~]$ kubectl get pod -n dev NAME      READY   STATUS    RESTARTS   AGE nginxss   1/1     Running   0          18s [qq@k8snode1 ~]$ kubectl get pod -n dev -o wide NAME      READY   STATUS    RESTARTS   AGE   IP           NODE       NOMINATED NODE   READINESS GATES nginxss   1/1     Running   0          43s   172.17.0.3   minikube                [qq@k8snode1 ~]$ kubectl describe pod nginxss -n dev 《查看详细的pod信息》 Name:         nginxss Namespace:    dev Priority:     0 Node:         minikube/192.168.49.2 Start Time:   Sat, 19 Feb 2022 18:29:18 +0800 Labels:       run=nginxss Annotations:   Status:       Running IP:           172.17.0.3 IPs:   IP:  172.17.0.3 Containers:   nginxss:     Container ID:   docker://386271d32e3a74ac5837c671d177cd2f28ff6ecf5b62c52bee0fbae3b34ae0e1     Image:          nginx:1.17.1     Image ID:       docker-pullable://nginx@sha256:b4b9b3eee194703fc2fa8afa5b7510c77ae70cfba567af1376a573a967c03dbb     Port:           80/TCP     Host Port:      0/TCP     State:          Running       Started:      Sat, 19 Feb 2022 18:29:19 +0800     Ready:          True     Restart Count:  0     Environment:         Mounts:       /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-7hqgp (ro) Conditions:   Type              Status   Initialized       True   Ready             True   ContainersReady   True   PodScheduled      True Volumes:   kube-api-access-7hqgp:     Type:                    Projected (a volume that contains injected data from multiple sources)     TokenExpirationSeconds:  3607     ConfigMapName:           kube-root-ca.crt     ConfigMapOptional:            DownwardAPI:             true QoS Class:                   BestEffort Node-Selectors:               Tolerations:                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s                              node.kubernetes.io/unreachable:NoExecute op=Exists for 300s Events:   Type    Reason     Age    From               Message   ----    ------     ----   ----               -------   Normal  Scheduled  2m50s  default-scheduler  Successfully assigned dev/nginxss to minikube   Normal  Pulled     2m49s  kubelet            Container image ＂nginx:1.17.1＂ already present on machine   Normal  Created    2m49s  kubelet            Created container nginxss   Normal  Started    2m49s  kubelet            Started container nginxss  [qq@k8snode1 ~]$ kubectl delete  pod nginxss  -n dev pod ＂nginxss＂ deleted 《用delete干掉》 [qq@k8snode1 ~]$ kubectl delete ns dev namespace ＂dev＂ deleted   [qq@k8snode1 ~]$ kubectl get pod -A NAMESPACE     NAME                               READY   STATUS    RESTARTS      AGE kube-system   coredns-64897985d-bnkbc            1/1     Running   0             25m kube-system   etcd-minikube                      1/1     Running   1             25m kube-system   kube-apiserver-minikube            1/1     Running   2             25m kube-system   kube-controller-manager-minikube   1/1     Running   1             25m kube-system   kube-proxy-tgbx2                   1/1     Running   0             25m kube-system   kube-scheduler-minikube            1/1     Running   1             25m kube-system   storage-provisioner                1/1     Running   2 (25m ago)   25m
　　命令式对象配置，使用yaml创建pod，上面的是pod的下面的是命名空间的 apiVersion: v1 kind: Pod metadata:   name: nginx   namespace: dev spec:   containers:   - image: nginx:latest     name: pod     ports:     - name: nginx-port       containerPort: 80       protocol: TCPapiVersion: v1 kind: Namespace metadata:   name: dev 命令式对象配置的创建和删除[qq@k8snode1 ~]$ ll 总用量 12 -rw-rw-r--. 1 qq qq  43 2月  11 20:02 2022-02-11 -rw-rw-r--. 1 qq qq  54 2月  14 18:57 devns.yaml -rw-rw-r--  1 qq qq 202 2月  19 18:58 nginx.yaml [qq@k8snode1 ~]$ kubectl create -f devns.yaml namespace/dev created [qq@k8snode1 ~]$ kubectl create -f nginx.yaml pod/nginx created  [qq@k8snode1 ~]$ kubectl delete -f nginx.yaml pod ＂nginx＂ deleted [qq@k8snode1 ~]$ kubectl delete -f devns.yaml namespace ＂dev＂ deleted [qq@k8snode1 ~]$