k8s常用资源管理

Pod（容器组）：Pod是Kubernetes中最小的部署单元，可以包含一个或多个容器。Pod提供了一种逻辑上的封装，使得容器可以一起共享网络和存储资源

1、创建一个pod

1）创建yuml文件

$root@k8s-master \~\]# mkdir k8s \[root@k8s-master \~\]# vim ./k8s/nginx.yaml piVersion: v1 kind: Pod metadata: name: nginx labels: app: web spec: containers: - name: nginx image: nginx:1.13 ports: - containerPort: 80$

2）创建容器

方法一. yum安装
$root@k8s-master \~\]#yum install \*rhsm\* 方法二执行命令： \[root@k8s-master \~\]#wget [http://mirror.centos.org/centos/7/os/x86_64/Packages/python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm](http://mirror.centos.org/centos/7/os/x86_64/Packages/python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm "http://mirror.centos.org/centos/7/os/x86_64/Packages/python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm") \[root@k8s-master \~\]# yum -y install \*rhsm\* \[root@k8s-master \~\]# wget http://mirror.centos.org/centos/7/os/x86_64/Packages/python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm \[root@k8s-master \~\]# rpm2cpio python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm \| cpio -iv --to-stdout ./etc/rhsm/ca/redhat-uep.pem \| tee /etc/rhsm/ca/redhat-uep.pem 前两个命令会生成/etc/rhsm/ca/redhat-uep.pem文件. ![](https://file.jishuzhan.net/article/1689802704638971905/8726a88a780a4fd19f060bb7af904dd7.png) \[root@k8s-master \~\]# docker pull registry.access.redhat.com/rhel7/pod-infrastructure:latest Trying to pull repository registry.access.redhat.com/rhel7/pod-infrastructure ... latest: Pulling from registry.access.redhat.com/rhel7/pod-infrastructure 26e5ed6899db: Downloading 34.95 MB/74.87 MB 66dbe984a319: Download complete 9138e7863e08: Download complete$

创建pod

$root@k8s-master \~\]# kubectl create -f ./k8s/nginx.yaml pod "nginx" created$

3）查看所有pod创建运行状态

$root@k8s-master \~\]# kubectl get pod NAME READY STATUS RESTARTS AGE nginx 0/1 ContainerCreating 0 17s$

4）查看指定pod资源

$root@k8s-master \~\]# kubectl get pod nginx NAME READY STATUS RESTARTS AGE nginx 0/1 ContainerCreating 0 41s$

5）查看pod运行的详细信息

root@k8s-master \~\]# kubectl describe pod nginx > Name: nginx > > Namespace: default > > Node: k8s-node2/192.168.50.51 > > Start Time: Thu, 10 Aug 2023 20:33:09 +0800 > > Labels: app=web > > Status: Pending > > IP: > > Controllers: \ > > Containers: > > nginx: > > Container ID: > > Image: nginx:1.13 > > Image ID: > > Port: 80/TCP > > State: Waiting > > Reason: ContainerCreating > > Ready: False > > Restart Count: 0 > > Volume Mounts: \ > > Environment Variables: \ > > Conditions: > > Type Status > > Initialized True > > Ready False > > PodScheduled True > > No volumes. > > QoS Class: BestEffort > > Tolerations: \ > > Events: > > FirstSeen LastSeen Count From SubObjectPath Type ReasonMessage > > --------- -------- ----- ---- ------------- -------- ------------- > > 1m 1m 1 {default-scheduler } Normal Scheduled Successfully assigned nginx to k8s-node2 > > 25s 25s 1 {kubelet k8s-node2} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \\"registry.access.redhat.com/rhel7/pod-infrastructure:latest\\"" > > 1m 4s 3 {kubelet k8s-node2} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull failed for registry.access.redhat.com/rhel7/pod-infrastructure:latest, this may be because there are no credentials on this request. details: (open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory)" 显示调度节点 验证运行的pod \[root@k8s-master \~\]# kubectl get pod nginx -o wide NAME READY STATUS RESTARTS AGE IP NODE nginx 0/1 ContainerCreating 0 2m \ k8s-node2 ### ******2、pod管理****** 1）删除pod > \[root@k8s-master \~\]# kubectl delete pod nginx > > pod "nginx" deleted 2）查看删除pod无法找到 > \[root@k8s-master \~\]# kubectl get pod nginx -o wide > > Error from server (NotFound): pods "nginx" not found 3）创建pod > \[root@k8s-master \~\]# kubectl create -f ./k8s/nginx.yaml > > pod "nginx" created 4）发现最先创建的pod运行在k8s-master节点上，下载镜像速度太慢没法运行 > \[root@k8s-master \~\]# kubectl get pod nginx -o wide > > NAME READY STATUS RESTARTS AGE IP NODE > > nginx 0/1 ContainerCreating 0 38s \ k8s-master 5）访问pod节点中的服务 > \[root@k8s-master \~\]# kubectl get pod nginx -o wide > > NAME READY STATUS RESTARTS AGE IP NODE > > nginx 1/1 Running 0 21m 172.16.48.2 k8s-master > > > \[root@k8s-master \~\]# curl -l http://172.16.48.2 > > \ > > \ > > \ > > \Welcome to nginx!\ > > \ > > body { > > width: 35em; > > margin: 0 auto; > > font-family: Tahoma, Verdana, Arial, sans-serif; > > } > > \ > > \ > > \ > > \Welcome to nginx!\ > > \If you see this page, the nginx web server is successfully installed and > > working. Further configuration is required.\ > > \For online documentation and support please refer to > > \nginx.org\.\ > > Commercial support is available at > > \nginx.com\.\ > > \\Thank you for using nginx.\\ > > \ > > \ ### ******pod操作****** 1）在一个pod中修改配置文件运行多个业务容器 > \[root@k8s-master \~\]# vim ./k8s/nginx.yaml > > apiVersion: v1 > > kind: Pod > > metadata: > > name: test3 > > labels: > > app: web > > spec: > > containers: > > - name: nginx02 > > image: nginx:1.13 > > ports: > > - containerPort: 80 > > - name: busybox > > image: docker.io/busybox:latest > > command: \["sleep","3600"

ports:

containerPort: 80

~

2）创建资源

$root@k8s-master \~\]# kubectl create -f ./k8s/nginx.yaml$

3）查看资源使用情况 Pod会分配了各自的 IP 过程会有点慢正常现象

$root@k8s-master \~\]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE nginx 1/1 Running 0 25m 172.16.48.2 k8s-master test1 0/2 ContainerCreating 0 9m \ k8s-node2 test2 2/2 Running 0 5m 172.16.48.3 k8s-master test3 0/2 ContainerCreating 0 4m \ k8s-node2$