何为容器化应用？
通俗来说，就是你把一个程序放在docker里部署，这个docker应用就是容器化应用；
比如：在docker里面部署一个springboot,这个docker + springboot一起就是一个容器化应用；
在Docker里面部署一个nginx ,这个docker + nginx一起就是一个容器化应用；
在Docker里面部署一个应用怎么部署？
就是 ： 镜像 -> 启动镜像得到一个Docker容器；
在K8S里面怎么部署？
SpringBoot程序 --> 打包一个jar包或war包-->通过Dockerfile文件生成docker镜像-->通过K8s部署这个镜像-->部署完毕；
总结一下Kubernetes部署容器化应用的步骤：
1.制作镜像（自己Dockerfile文件制作，或者从仓库pull）
2.通过控制管理器pod(其实就是把镜像启动得到一个容器， 容器在pod里)
3.暴露应用，以便外界可以访问；
在Kubernetes集群中部署一个Nginx
kubectl create deployment nginx --image=nginx#拉取nginx镜像并启动
kubectl expose deployment nginx --port=80 --type=NodePort #暴露端口（使用了这个命令之后查看service才可以查到）
kubectl get pod,svc
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4.访问应用
kubectl get nodes
kubectl get service(s)
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kubectl get deployment(deploy)
kubectl get pod(s)
页面访问的时候是node节点的阿里云ip:暴露的端口号
[root@master ~]# netstat -nlpt # 查看端口
#如果上面这个命令找不到要先安装一个
#yum install net-tools -y #安装网络工具
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.1:10248 0.0.0.0:* LISTEN 32461/kubelet
tcp 0 0 127.0.0.1:10249 0.0.0.0:* LISTEN 311/kube-proxy
tcp 0 0 172.31.197.181:2379 0.0.0.0:* LISTEN 32114/etcd
tcp 0 0 127.0.0.1:2379 0.0.0.0:* LISTEN 32114/etcd
tcp 0 0 172.31.197.181:2380 0.0.0.0:* LISTEN 32114/etcd
tcp 0 0 127.0.0.1:2381 0.0.0.0:* LISTEN 32114/etcd
tcp 0 0 0.0.0.0:31054 0.0.0.0:* LISTEN 311/kube-proxy
tcp 0 0 127.0.0.1:10257 0.0.0.0:* LISTEN 32090/kube-controll
tcp 0 0 127.0.0.1:10259 0.0.0.0:* LISTEN 32140/kube-schedule
tcp 0 0 127.0.0.1:41492 0.0.0.0:* LISTEN 32461/kubelet
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1045/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1001/master
tcp6 0 0 :::10250 :::* LISTEN 32461/kubelet
tcp6 0 0 :::6443 :::* LISTEN 32072/kube-apiserve
tcp6 0 0 :::10256 :::* LISTEN 311/kube-proxy
tcp6 0 0 ::1:25
[root@master ~]# kubectl get pod(s s可以省略)
NAME READY STATUS RESTARTS AGE
nginx-6799fc88d8-rp57r 1/1 Running 0 17h
[root@master ~]# kubectl --help # 查询有哪些命令
[root@master ~]# kubectl get deployment(deploy 可以简写) # 查控制器
NAME READY UP-TO-DATE AVAILABLE AGE
nginx 1/1 1 1 17h
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[root@master ~]# kubectl get service #查看service
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 19h
nginx NodePort 10.96.186.10 <none> 80:31054/TCP 17h
# 80是集群内部访问 31054是外界访问端口
[root@master ~]# kubectl get services
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 19h
nginx NodePort 10.96.186.10 <none> 80:31054/TCP 17h
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[root@master ~]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
nginx 1/1 1 1 18h
[root@master ~]# kubectl delete deployment nginx #删除nginx控制器
deployment.apps "nginx" deleted
[root@master ~]# kubectl get pods
No resources found in default namespace.
#kubectl delete pod pod的名字 #删除Pod
# kubectl delete pod nginx-6799fc88d8-rp57r #删除pod
[root@master ~]# kubectl get service
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 19h
nginx NodePort 10.96.186.10 <none> 80:31054/TCP 18h
[root@master ~]# kubectl delete service nginx #删除service
service "nginx" deleted
[root@master ~]# systemctl restart docker
[root@master ~]# kubectl create deployment nginx --image=nginx
deployment.apps/nginx created
[root@master ~]# kubectl expose deployment nginx --port=80 --type=NodePort
service/nginx exposed
[root@master ~]# kubectl get pod,svc
NAME READY STATUS RESTARTS AGE
pod/nginx-6799fc88d8-kqfmm 1/1 Running 0 42s
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 22h
service/nginx NodePort 10.98.160.67 <none> 80:32169/TCP 15s
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页面访问是使用 （发现master和node节点的公网ip都可以访问） 阿里云公网ip :暴露的端口 注意暴露的端口需要在阿里云的安全组配置
在Kubernetes集群中部署一个Tomcat
拉取下拉的镜像是部署在node节点上（在node上查看docker images 查看是否把镜像拉取下来），不会部署在master节点上，虽然是在master节点上操作的
kubectl create deployment tomcat --image=tomcat
kubectl expose deployment tomcat --port=8080 --type=NodePort
kubectl get pod,svc
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[root@master ~]# kubectl create deployment tomcat --image=tomcat
deployment.apps/tomcat created
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
tomcat-7d987c7694-vnwv9 1/1 Running 0 2m56s
[root@master ~]# kubectl get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
tomcat 1/1 1 1 4m15s
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[root@master ~]# kubectl get deploy -n kube-system #查看系统控制器有哪些
NAME READY UP-TO-DATE AVAILABLE AGE
coredns 2/2 2 2 19h
[root@master ~]# kubectl get namespace #查看命名空间
NAME STATUS AGE
default Active 20h
kube-node-lease Active 20h
kube-public Active 20h
kube-system Active 20h
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[root@master ~]# kubectl describe pods tomcat-7d987c7694-vnwv9 #查看详情的命令
Name: tomcat-7d987c7694-vnwv9
Namespace: default
Priority: 0
Node: node01/172.31.197.180
Start Time: Sun, 06 Jun 2021 16:22:39 +0800
Labels: app=tomcat
pod-template-hash=7d987c7694
Annotations: <none>
Status: Running
IP: 10.244.1.3
IPs:
IP: 10.244.1.3
Controlled By: ReplicaSet/tomcat-7d987c7694
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#删除tomcat
kubectl delete deploy tomcat
[root@master ~]# kubectl delete deploy tomcat
deployment.apps "tomcat" deleted
[root@master ~]# kubectl get pods
No resources found in default namespace.
[root@master ~]# kubectl get service
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 22h
tomcat NodePort 10.107.183.58 <none> 8080:30495/TCP 154m
[root@master ~]# kubectl delete service tomcat
service "tomcat" deleted
[root@master ~]# kubectl get service
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 22h
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上面的部署 tomcat在浏览器访问相关端口没有访问成功
在Kubernetes集群中部署SpringBoot应用
1.项目打包（jar, war）-->可以采用一些工具git、maven、jenkinx
2.制作Dockerfile文件，生成镜像
3.kubectl create deployment your-springboot --image=你的镜像
4.你的springboot就部署好了，是以docker容器的方式运行在pod里面的；
Master控制Node --> service --> deployment(控制器) --> pod -->docker
部署Kubernetes Dashboard
Kubernetes仪表盘是Kubernetes集群的基于Web的通用UI，它允许用户管理集群中运行的应用程序并对其进行故障排除，已经管理集群本身；
wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.4/aio/deploy/recommended.yaml
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kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.4/aio/deploy/recommended.yaml
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root@master ~]# wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.4/aio/deploy/recommended.yaml
--2021-06-06 21:18:19-- https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.4/aio/deploy/recommended.yaml
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 185.199.111.133, 185.199.108.133, 185.199.109.133, ...
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|185.199.111.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 7552 (7.4K) [text/plain]
Saving to: ‘recommended.yaml’
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100%[==========================================================================================================================================>] 7,552 9.79KB/s in 0.8s
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2021-06-06 21:18:21 (9.79 KB/s) - ‘recommended.yaml’ saved [7552/7552]
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[root@master ~]# kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.4/aio/deploy/recommended.yaml
namespace/kubernetes-dashboard unchanged
serviceaccount/kubernetes-dashboard unchanged
service/kubernetes-dashboard unchanged
secret/kubernetes-dashboard-certs unchanged
secret/kubernetes-dashboard-csrf configured
Warning: resource secrets/kubernetes-dashboard-key-holder is missing the kubectl.kubernetes.io/last-applied-configuration annotation which is required by kubectl apply. kubectl apply should only be used on resources created declaratively by either kubectl create --save-config or kubectl apply. The missing annotation will be patched automatically.
secret/kubernetes-dashboard-key-holder configured
configmap/kubernetes-dashboard-settings unchanged
role.rbac.authorization.k8s.io/kubernetes-dashboard unchanged
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard unchanged
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard unchanged
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard unchanged
deployment.apps/kubernetes-dashboard configured
service/dashboard-metrics-scraper unchanged
deployment.apps/dashboard-metrics-scraper configured
[root@master ~]# vim recommended.yaml
[root@master ~]# kubectl get pods -n kubernetes-dashboard
NAME READY STATUS RESTARTS AGE
dashboard-metrics-scraper-7b59f7d4df-67tqb 1/1 Running 0 7m52s
kubernetes-dashboard-665f4c5ff-lt78w 1/1 Running 0 7m52s
#查看service,type类型已经编程为NodePort端口为30001
[root@master ~]# kubectl get service -n kubernetes-dashboard | grep dashboard
dashboard-metrics-scraper ClusterIP 10.99.41.254 <none> 8000/TCP 95m
kubernetes-dashboard NodePort 10.103.73.21 <none> 443:30001/TCP 95m
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访问页面：
注意要在阿里云安全组里面把对应的端口开启
kubectl get service -n kubernetes-dashboard | grep dashboard # 查看对应的端口
获取token的命令（如果下次再获取token就只用执行最后一个命令就行 因为前两个命令再次执行会报错）
1.#kubectl create serviceaccount dashboard-admin -n kube-system
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2.#kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
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3.#kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | grep admin-user | awk ‘{print $1}‘)
把生成的token粘贴到上面的仪表盘的token中就有了下面这个页面
安装vim的命令
yum install vim -y
改配置文件要重启docker命令
systemctl restart docker
B站学习网址：