Kubernetes快速入门

Kubernetes快速入门

环境准备:

　　关闭CentOS防火墙

systemctl disable fifirewalld
systemctl stop fifirewalld

　　安装etcd和kubernetes软件

yum install -y etcd kubernetes

　　启动服务

systemctl start etcd
systemctl start docker

注意:如果docker启动失败，请参考(vi /etc/sysconfig/selinux 把selinux后面的改为disabled，重启一波 机器，再重启docker就可以了)

systemctl start kube-apiserver
systemctl start kube-controller-manager
systemctl start kube-scheduler
systemctl start kubelet
systemctl start kube-proxy

配置

Tomcat配置

　　mytomcat.rc.yaml

apiVersion: v1 
kind: ReplicationController 
metadata: 
 name: mytomcat 
spec: 
 replicas: 2 
 selector: 
  app: mytomcat 
template: 
 metadata: 
  labels: 
   app:mytomcat 
 spec: 
  containers: 
   - name: mytomcat 
     image: tomcat:7-jre7 
     ports: 
      - containerPort: 8080

执行命令创建ReplicationController:

kubectl create -f mytomcat.rc.yaml

mytomcat.svc.yaml

apiVersion: v1 
kind: Service 
metadata: 
 name: mytomcat 
spec: 
 type: NodePort 
ports: 
 - port: 8080 
   nodePort: 30001 
selector: 
 app: mytomcat

执行命令创建Service:

kubectl create -f mytomcat.svc.yaml

问题解决:

docker pull失败

解决方案1:

1、yum install rhsm -y
2、docker pull registry.access.redhat.com/rhel7/pod-infrastructure:latest
如果以上两步解决问题了，那么就不需要在执行下面操作:
3、docker search pod-infrastructure
4、docker pull docker.io/tianyebj/pod-infrastructure
5、docker tag tianyebj/pod-infrastructure 192.168.126.143:5000/pod-infrastructure
6、docker push 192.168.126.143:5000/pod-infrastructure
7、vi /etc/kubernetes/kubelet
修改 KUBELET_POD_INFRA_CONTAINER="--pod-infra-container
image=192.168.126.143:5000/pod- infrastructure:latest"
8、重启服务
systemctl restart kube-apiserver systemctl restart kube-controller-manager systemctl restart
kube-scheduler systemctl restart kubelet systemctl restart kube-proxy

解决方案2:

1、docker pull kubernetes/pause
2、docker tag docker.io/kubernetes/pause:latest
192.168.126.143:5000/google_containers/pause-amd64.3.0
3、docker push 192.168.126.143:5000/google_containers/pause-amd64.3.0
4、vi /etc/kubernetes/kubelet配置为
KUBELET_ARGS="--
pod_infra_container_image=192.168.126.143:5000/google_containers/pause-amd64.3.0"
5、重启kubelet服务 systemctl restart kubelet

外部网不能访问

在搭建好的k8s集群内创建的容器，只能在其所在的节点上curl可访问，但是在其他任何主机上无法访问容器占用的端口

解决方案：

1、vim /etc/sysctl.conf
2、net.ipv4.ip_forward=1

解决 kubectl get pods时No resources found问题:

1、vim /etc/kubernetes/apiserver
2、找到”KUBE_ADMISSION_CONTROL="-admission_control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"，去掉ServiceAccount，保存退出。
3、systemctl restart kube-apiserver

重启此服务

浏览测试: