[PHP知识库]K8S1.21.1学习笔记

pod

#创建ns，先有才能创建pod
[root@node2 pod]# cd /root/myk8s/pod
[root@node2 pod]# cat test-pod.yaml
apiVersion: v1
kind: Pod
metadata:
  name: busybox
  namespace: myk8s
spec:
  containers:
  - name: busybox
    image: 127.0.0.1/myk8s/busybox
    command:
      - sleep
      - "3600"
    imagePullPolicy: IfNotPresent
  restartPolicy: Always
  
[root@node2 pod]# kubectl create ns myk8s
[root@node2 pod]# kubectl get ns
[root@node2 pod]# kubectl create -f test-pod.yaml

[root@node2 pod]# kubectl get pod --namespace=myk8s
#删除容器
[root@node2 pod]# kubectl delete pods busybox --namespace=myk8s

#查看日志
[root@node2 pod]# kubectl logs busybox --namespace=myk8s
#查看pod细节
[root@node2 pod]# kubectl describe pod busybox --namespace=myk8s

#使用edit，修改配置
[root@node2 pod]# kubectl edit ns myk8s
[root@node2 pod]# kubectl edit pod busybox --namespace=myk8s

[root@node2 pod]# vim test-pod.yaml
[root@node2 pod]# kubectl apply -f test-pod.yaml

#修改yaml后，更新pod
[root@node2 pod]# kubectl apply -f nginx-pod.yaml
[root@node2 pod]# kubectl describe pod nginx
[root@node2 pod]# docker pull nginx

#有yaml情况下，重启pending状态pod
[root@node2 pod]# kubectl replace --force -f nginx-pod.yaml
[root@node2 pod]# kubectl logs nginx

#
[root@node2 pod]# kubectl get pods -o wide
NAME      READY   STATUS    RESTARTS   AGE     IP            NODE     NOMINATED NODE   READINESS GATES
busybox   1/1     Running   0          17m     172.30.2.10   node16   <none>           <none>
nginx     1/1     Running   0          2m40s   172.30.1.9    node3    <none>           <none>
[root@node2 pod]# curl http://172.30.1.9

• ?deployment

[root@node2 pod]# mkdir deployment
[root@node2 deployment]# rz
[root@node2 deployment]# vim nginx-deploy.yaml
[root@node2 deployment]# kubectl create -f nginx-deploy.yaml

#实时查看pod状态变化
[root@node2 ~]# watch -d -n 1 kubectl get pods -o wide


[root@node2 deployment]# vim nginx-deploy.yaml
[root@node2 deployment]# kubectl apply -f nginx-deploy.yaml

[root@node2 ~]# curl 172.30.2.22 -I
[root@node2 ~]# curl 172.30.2.22
[root@node2 ~]# kubectl logs -f nginx-deploy-7848d4b86f-48cqm

• service

[root@node2 service]# kubectl apply -f nginx-svc.yaml
[root@node2 service]# kubectl get svc -o wide
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE   SELECTOR
kubernetes   ClusterIP   10.254.0.1      <none>        443/TCP        24h   <none>
nginx-svc    NodePort    10.254.55.107   <none>        80:32291/TCP   10s   app=nginx


#配置nodeport；访问CLUSTER-IP:port 10.254.55.107:80ok的、 10.254.55.107:32291是不行的、可访方式nodeip:nodeport即10.206.0.2/3/16:32291 都可
[root@node2 myk8s]# kubectl get svc -n default
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.254.0.1      <none>        443/TCP        25h
nginx-svc    NodePort    10.254.55.107   <none>        80:32291/TCP   5m8s


#删除nodeport配置 即clusterip模式、配置node为11180；访问 10.254.55.107：11180
[root@node2 myk8s]# kubectl get svc
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)     AGE
kubernetes   ClusterIP   10.254.0.1      <none>        443/TCP     25h
nginx-svc    ClusterIP   10.254.55.107   <none>        11180/TCP   10m


#所以IP，有几个层面的。POD IP;POD CLUSTER IP(SERVICE层面)；NODE IP（集群NODE节点IP）
#POD IP：PORT
#CLUSTER IP：PORT（未配置NodePort）；SERVICE 配置后，即有了 CLUSTER IP
#NODE IP：PORT（配置NodePort）、以及 CLUSTER IP：PORT 均可访问

• 集群node状态?

[root@node3 ~]# systemctl status kubelet.service
[root@node3 ~]# systemctl status kubelet

?

• top

[root@node2 metrics-server0.5.0]# kubectl top pod nginx-deploy-7848d4b86f-24f82
error: Metrics API not available

[root@node2 metrics-server0.5.0]# pwd
/root/metrics-server0.5.0

[root@node2 metrics-server0.5.0]# kubectl apply -f components.yaml
serviceaccount/metrics-server created
clusterrole.rbac.authorization.k8s.io/system:aggregated-metrics-reader created
clusterrole.rbac.authorization.k8s.io/system:metrics-server created
rolebinding.rbac.authorization.k8s.io/metrics-server-auth-reader created
clusterrolebinding.rbac.authorization.k8s.io/metrics-server:system:auth-delegator created
clusterrolebinding.rbac.authorization.k8s.io/system:metrics-server created
service/metrics-server created
deployment.apps/metrics-server created


[root@node2 metrics-server-0.5.0]# kubectl delete -f ../../kubesphere/components.yaml

[root@node2 metrics-server0.5.0]# wget https://github.com/kubernetes/kubernetes/blob/4e30c058c4f73f8cf543501efaff44700867d7fa/cluster/addons/metrics-server/metrics-server-deployment.yaml

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