k8s基础知识复习

一 实验环境

服务器版本	docker软件版本	Kubernetes(k8s)集群版本	CPU架构
Ubuntu 20.04.4 LTS 20.04	Docker version 20.10.13	v1.23.3+k3s1	模拟

服务器	操作系统版本	CPU架构	进程	功能描述
master01	Ubuntu 20.04.4 LTS 20.04	模拟	docker，kubelet ,k3s相关	k3s master节点
slave01	Ubuntu 20.04.4 LTS 20.04	模拟	docker，kubelet， k3s相关	k3s worker节点
slave02	Ubuntu 20.04.4 LTS 20.04	模拟	docker，kubelet，k3s相关	k3s worker节点

二 实验事项

2.1 查看相关

kubectl get node #查看node
kubectl get node -o wide #查看扩展信息
kubectl get describe node master01 #查看 node master01 配置详情信息
kubectl get node slave01 -o yaml # 查看slave01 yaml格式
kubectl get node --show-labels. # 多现实标签信息

其它：namespace、deployment、pod等资源，都可以通过上面类似信息查看

# 查看node
ubuntu@master01:~$ sudo kubectl get node
NAME       STATUS   ROLES                  AGE    VERSION
slave02    Ready    <none>                 332d   v1.23.3+k3s1
master01   Ready    control-plane,master   332d   v1.23.3+k3s1
slave01    Ready    <none>                 332d   v1.23.3+k3s1
ubuntu@master01:~$ 

#查看node详情
ubuntu@master01:~$ sudo kubectl get node -o wide 
NAME       STATUS   ROLES                  AGE    VERSION        INTERNAL-IP     EXTERNAL-IP   OS-IMAGE             KERNEL-VERSION      CONTAINER-RUNTIME
master01   Ready    control-plane,master   332d   v1.23.3+k3s1   192.168.64.45   <none>        Ubuntu 20.04.4 LTS   5.4.0-137-generic   containerd://1.5.9-k3s1
slave01    Ready    <none>                 332d   v1.23.3+k3s1   192.168.64.46   <none>        Ubuntu 20.04.4 LTS   5.4.0-137-generic   containerd://1.5.9-k3s1
slave02    Ready    <none>                 332d   v1.23.3+k3s1   192.168.64.47   <none>        Ubuntu 20.04.4 LTS   5.4.0-137-generic   containerd://1.5.9-k3s1
ubuntu@master01:~$

#查看具体标签
ubuntu@master01:~$ sudo kubectl get node --show-labels
NAME       STATUS   ROLES                  AGE    VERSION        LABELS
master01   Ready    control-plane,master   332d   v1.23.3+k3s1   beta.kubernetes.io/arch=arm64,beta.kubernetes.io/instance-type=k3s,beta.kubernetes.io/os=linux,kubernetes.io/arch=arm64,kubernetes.io/hostname=master01,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=true,node-role.kubernetes.io/master=true,node.kubernetes.io/instance-type=k3s
slave01    Ready    <none>                 332d   v1.23.3+k3s1   beta.kubernetes.io/arch=arm64,beta.kubernetes.io/instance-type=k3s,beta.kubernetes.io/os=linux,kubernetes.io/arch=arm64,kubernetes.io/hostname=slave01,kubernetes.io/os=linux,node.kubernetes.io/instance-type=k3s
slave02    Ready    <none>                 332d   v1.23.3+k3s1   beta.kubernetes.io/arch=arm64,beta.kubernetes.io/instance-type=k3s,beta.kubernetes.io/os=linux,kubernetes.io/arch=arm64,kubernetes.io/hostname=slave02,kubernetes.io/os=linux,node.kubernetes.io/instance-type=k3s
ubuntu@master01:~$

#yaml格式
ubuntu@master01:~$ sudo kubectl get node master01 -o yaml
apiVersion: v1
kind: Node
metadata:
  annotations:
    flannel.alpha.coreos.com/backend-data: '{"VNI":1,"VtepMAC":"6a:ad:2e:8e:81:15"}'
    flannel.alpha.coreos.com/backend-type: vxlan
    flannel.alpha.coreos.com/kube-subnet-manager: "true"
省略

#查看node详情内容
ubuntu@master01:~$ sudo kubectl describe node master01
Name:               master01
Roles:              control-plane,master
Labels:             beta.kubernetes.io/arch=arm64
                    beta.kubernetes.io/instance-type=k3s
                    beta.kubernetes.io/os=linux
                    kubernetes.io/arch=arm64
                    kubernetes.io/hostname=master01
                    kubernetes.io/os=linux
                    node-role.kubernetes.io/control-plane=true
                    node-role.kubernetes.io/master=true
                    node.kubernetes.io/instance-type=k3s
Annotations:        flannel.alpha.coreos.com/backend-data: {"VNI":1,"VtepMAC":"6a:ad:2e:8e:81:15"}
                    flannel.alpha.coreos.com/backend-type: vxlan
                    flannel.alpha.coreos.com/kube-subnet-manager: true
                    flannel.alpha.coreos.com/public-ip: 192.168.64.45
                    k3s.io/hostname: master01
                    k3s.io/internal-ip: 192.168.64.45
                    k3s.io/node-args: ["server"]
省略

 

2.2 创建相关

#命令直接创建
ubuntu@master01:~$ sudo kubectl create namespace testlab
namespace/testlab created


#使用yaml格式创建
ubuntu@master01:~/learn$ cat testlab2.yaml 
apiVersion: v1
kind: Namespace
metadata:
  name: testlab2
ubuntu@master01:~/learn$ sudo kubectl apply -f testlab2.yaml 
namespace/testlab2 created
ubuntu@master01:~/learn$ sudo kubectl get ns
NAME              STATUS   AGE
default           Active   332d
kube-system       Active   332d
kube-public       Active   332d
kube-node-lease   Active   332d
test              Active   30m
testlab           Active   101s
testlab2          Active   7s
ubuntu@master01:~/learn$ 

2.3 修改或删除

#删除namespae testlab
ubuntu@master01:~/learn$ sudo kubectl delete ns testlab
namespace "testlab" deleted
ubuntu@master01:~/learn$ 

#命令修改
ubuntu@master01:~/learn$ sudo kubectl get ns testlab2 --show-labels
NAME       STATUS   AGE     LABELS
testlab2   Active   4m41s   kubernetes.io/metadata.name=testlab2
ubuntu@master01:~/learn$ sudo kubectl label ns testlab2 name=cka 
namespace/testlab2 labeled
ubuntu@master01:~/learn$ sudo kubectl get ns testlab2 --show-labels
NAME       STATUS   AGE    LABELS
testlab2   Active   5m5s   kubernetes.io/metadata.name=testlab2,name=cka
ubuntu@master01:~/learn$ sudo kubectl label ns testlab2 name=cka1  
error: 'name' already has a value (cka), and --overwrite is false
ubuntu@master01:~/learn$ sudo kubectl label ns testlab2 name=cka1  --overwrite
namespace/testlab2 labeled
ubuntu@master01:~/learn$ sudo kubectl get ns testlab2 --show-labels
NAME       STATUS   AGE     LABELS
testlab2   Active   5m31s   kubernetes.io/metadata.name=testlab2,name=cka1
ubuntu@master01:~/learn$ 

#yaml文件修改，直接编辑文件修改
ubuntu@master01:~/learn$ sudo kubectl apply -f testlab2.yaml 
namespace/testlab2 configured
ubuntu@master01:~/learn$ cat testlab2.yaml
apiVersion: v1
kind: Namespace
metadata:
  name: testlab2
  labels: {
     "env" : "prod"
  }
ubuntu@master01:~/learn$ sudo kubectl get ns testlab2 --show-labels
NAME       STATUS   AGE     LABELS
testlab2   Active   8m19s   env=prod,kubernetes.io/metadata.name=testlab2,name=cka1
ubuntu@master01:~/learn$