kubernetes最小集群搭建

修改记录

Master运行服务中，增加kube-proxy服务

1. 环境

Virtual Box
CentOS 7
yum install docker kubernetes flannel
虚拟机网络设置

新建虚拟网络A（在主机网络管理菜单），定义网段192.168.56.1/24，打开DHCP
所有主机创建两块网卡，外网NAT，内网选择虚拟网络vbox1

3台虚拟机设置

主机名	IP	配置
Master	192.168.56.4	1CPU，1G
node1	192.168.56.5	1CPU，1G
node2	192.168.56.6	1CPU，1G

2. 执行环境(无特殊说明，全部都要这样做)

三台主机互通
master ssh passwdless 访问其它两台主机
打开内核转发

添加net.ipv4.ip_forward 到/etc/sysctl.conf

修改Docker配置

修改/usr/lib/systemd/system/docker.service

service段增加 ExecStartPost=/sbin/iptables -I FORWARD -s 0.0.0.0/0 -j ACCEPT

修改/etc/sysconfig/docker

OPTIONS="--insecure-registry gcr.io --selinux-enabled=false"

禁用防火墙

  systemctl stop firewalld
  systemctl disable firewalld

关闭SElinux

修改/etc/selinux/config

修改SELINUX=disabled

修改Docker配置，增加镜像

  {
      "registry-mirrors":["http://hub-mirror.c.163.com"]
  }

设置时区与时间同步

yum -y install ntp
timedatectl  set-timezone Asia/Shanghai

3. 节点功能规划

Master 部分增加了kube-proxy，第一版忘记加了

主机名	运行的服务
Master	docker etcd kube-apiserver flanneld kube-proxy kube-controller-manager kube-scheduler
node1	docker flanneld kubelet kube-proxy
node2	docker flanneld kubelet kube-proxy

4. Master设置

设置etcd参数并启动

vim /etc/etcd/config
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
# 要注意这个参数的IP，这里因为是连接服务，不是监听，所以必须用IP，不能用0.0.0.0
ETCD_ADVERTISE_CLIENT_URLS="http://192.168.56.4:2379"

service etcd restart

其实ETCD_LISTEN_CLIENT_URLS怎么设置都无所谓，只要正常监听就可以。放到这里，可以设置为http://192.168.56.4:2379

设置flannel

vim /etc/sysconfig/flanneld
FLANNEL_ETCD_ENDPOINTS="http://192.168.56.4:2379"
FLANNEL_ETCD_PREFIX="/coreos.com/network"

稍后补充为什么这么设置

手动向etcd，设置flannel网段信息

etcdctl set /coreos.com/network/config '{ "Network": "10.254.0.0/16" }'

这里采用kubenetes默认值

修改kube-apiserver配置文件

  vim /etc/kubernetes/apiserver

  KUBE_ETCD_SERVERS="--etcd-servers=http://192.168.56.4:2379"

稍后测试，是否设置为127.0.0.1会影响node1,2的etcd获取。如果仅仅是影响api-server并且etcd与

api-server在同一台服务器，那么127应该也是可以的。

修改controller-manager


vim /etc/kubernetes/controller-manager

KUBE_CONTROLLER_MANAGER_ARGS="--node-monitor-grace-period=10s --pod-eviction-timeout=10s"

编辑kubenetes配置


vim /etc/kubenetes/config

KUBE_MASTER="--master=http://192.168.56.4:8080"

设置服务并启动


systemctl enable docker flanneld kube-apiserver kube-controller-manager kube-scheduler

systemctl start flanneld docker kube-proxy kube-apiserver kube-controller-manager kube-scheduler

5. Node节点设置

修改kubenetes配置


vim /etc/kubernetes/config

KUBE_MASTER="--master=http://192.168.56.4:8080"

修改kubelets配置


vim /etc/kubernetes/kubelet

KUBELET_ADDRESS="--address=0.0.0.0"

KUBELET_HOSTNAME="--hostname-override=192.168.56.5"

KUBELET_API_SERVER="--api-servers=http://192.168.56.4:8080"

修改flanneld


vim /etc/sysconfig/flanneld

FLANNEL_ETCD_ENDPOINTS="http://192.168.56.4:2379"

FLANNEL_ETCD_PREFIX="/coreos.com/network"

设置服务并启动


systemctl enable docker flanneld kubelet kube-proxy

systemctl start flanneld docker kubelet kube-proxy

6. 验证

验证节点


$kubectl get nodes -o wide

NAME          STATUS    AGE      EXTERNAL-IP

192.168.56.5  Ready    1h        <none>

192.168.56.6  Ready    1h        <none>

创建RC文件mysql-rc.yaml


apiVersion: v1

kind: ReplicationController

metadata:

  name: mysql-rc

spec:

  replicas: 1

  selector:

    app: mysql-pod

  template:

    metadata:

      labels:

        app: mysql-pod

    spec:

      containers:

      - name: mysql

        image: mysql:5.6

        ports:

        - containerPort: 3306

        env:

        - name: MYSQL_ROOT_PASSWORD

          value: "123"

创建Service文件mysql-svc.yaml


apiVersion: v1

kind: Service

metadata:

  name: mysql-svc

  labels:

    name: mysql-svc

spec:

  type: NodePort

  ports:

  - port: 3306

    protocol: TCP

    targetPort: 3306

    name: http

    nodePort: 30006

  selector:

    app: mysql-pod

运行


kubectl create -f mysql-rc.yaml

kubectl create -f mysql-svc.yaml

结果检查


$kubectl get pods -o wide

NAME            READY    STATUS    RESTARTS  AGE      IP          NODE

mysql-rc-82g2m  1/1      Running  0          1h        172.17.0.2  192.168.56.5

$kubectl get svc -o wide

NAME        CLUSTER-IP      EXTERNAL-IP  PORT(S)          AGE      SELECTOR

kubernetes  10.254.0.1      <none>        443/TCP          2d        <none>

mysql-svc    10.254.255.244  <nodes>      3306:30006/TCP  1h        app=mysql-pod

$kubectl get endpoints

NAME        ENDPOINTS            AGE

kubernetes  192.168.1.114:6443  2d

mysql-svc    172.17.0.2:3306      1h

全部关联上，创建没问题


$ mysql -uroot -p123 -P30006 -h 192.168.56.5

mysql>

mysql连接成功

k8s无脑系列（一）-最小集群搭建