目录
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
2、pod管理
pod操作
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
[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.
[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: <none>
Containers:
nginx:
Container ID:
Image: nginx:1.13
Image ID:
Port: 80/TCP
State: Waiting
Reason: ContainerCreating
Ready: False
Restart Count: 0
Volume Mounts: <none>
Environment Variables: <none>
Conditions:
Type Status
Initialized True
Ready False
PodScheduled True
No volumes.
QoS Class: BestEffort
Tolerations: <none>
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 <none> 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 <none> 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
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p><p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p><p><em>Thank you for using nginx.</em></p>
</body>
</html>
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 <none> k8s-node2
test2 2/2 Running 0 5m 172.16.48.3 k8s-master
test3 0/2 ContainerCreating 0 4m <none> k8s-node2
