『高级篇』docker之kubernetes基础集群命令小实战(
2018-11-13 本文已影响0人
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原文链接地址:『高级篇』docker之kubernetes基础集群命令小实战(35)
下面我们就来试试看怎么去操作,控制它。我们从最简单的命令开始,尝试一下kubernetes官方的入门教学:playground的内容。了解如何创建pod,deployments,以及查看他们的信息,深入理解他们的关系。源码:https://github.com/limingios/msA-docker k8s分支和https://github.com/limingios/kubernetes-starter 基础集群的搭建查看32节到34节
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kubernetes接触命令
- kubectl version
查看版本
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- kubectl get nodes
查看nodes
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- kubectl get pods
查看pods
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- 拉取官方的镜像
内存有点低比较慢
kubectl run kubernetes-bootcamp --image=jocatalin/kubernetes-bootcamp:v1 --port=8080
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- 查看deploy的详细信息
kubectl describe deploy kubernetes-bootcamp
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- 查看pods的详细信息
kubectl describe pods kubernetes-bootcamp-6b7849c495-xmmvh
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- 如何访问刚才那个8080端口因为它在103那台机器上,可以通过apiserver的方式
启动2个窗口,一个窗口启动代理命令,
kubectl proxy
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然后操作另一个窗口
curl http://localhost:8001/api/v1/proxy/namespaces/default/pods/kubernetes-bootcamp-6b7849c495-xmmvh/
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- 扩缩容
k8s会均匀的使用机器,不会存在一台机器用的很多,一台机器用的很少的情况。
#如果需要从2 变成1 直接还用这个命令
kubectl scale deploy kubernetes-bootcamp --replicas=2
#可以看到在102运行了一个实例,在103在运行了一个实例
kubectl get pods -o wide
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- 升级镜像
目前状态
kubectl describe deploy kubernetes-bootcamp
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升级镜像
#原来是v1升级为v2
kubectl set image deploy kubernetes-bootcamp kubernetes-bootcamp=jocatalin/kubernetes-bootcamp:v2
kubectl describe deploy kubernetes-bootcamp
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deploy的状态
kubectl rollout status deploy kubernetes-bootcamp
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回滚镜像
kubectl rollout undo deploy kubernetes-bootcamp
#又变回v1了
kubectl describe deploy kubernetes-bootcamp
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删除deploy
kubectl delete deploy kubernetes-bootcamp
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配置文件
上边用了比较多的命令了,老铁消化吸收一下,当然一直使用命令管理集群真的很不方便,当拥有大量的应用的时候很难胜任了,k8s也提供了配置文件的方式来管理。跟swarm的有点类似吧。设计和功能上有点区别。
- yaml文件创建pod
mkdir services
cd services
vi nginx-pod.yaml
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nginx-pod.yaml 文件
apiVersion: v1
kind: Pod
metadata:
name: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
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命令生成pod
kubectl create -f nginx-pod.yaml
#文件写明的创建pod,就不可能创建deploy
kubectl get deploy
kubectl get pods -o wide
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启动代理尝试访问nginx
老套路,一个窗口启动,一个窗口curl
#ip101启动代理
kubectl proxy
#ip101另一个窗口访问
curl http://localhost:8001/api/v1/proxy/namespaces/default/pods/nginx/
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- yaml文件创建deployment
vi nginx-Deployment.yaml
nginx-Deployment.yaml 文件
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 2
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
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命令生成deployment
kubectl create -f nginx-Deployment.yaml
kubectl get deploy
kubectl get pods -o wide
kubectl get pods -l app=nginx
kubectl get pods -l app=nginx -o wide
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PS:常用的命令就说到这里吧,下次继续说说service和dns。