首页 > 技术文章 > Kubernetes V1.17集群部署并部署Metrics Server插件(一)无坑!!!

shunzi115 2020-03-07 22:03 原文

环境信息:

操作系统 主机名 IP地址
CentOS 7.6 k8s-master 9.110.187.20
CentOS 7.6 k8s-node1 9.110.187.23
CentOS 7.6 k8s-node2 9.110.187.24

1. 安装环境

在开始之前,部署Kubernetes集群机器需要满足以下几个条件:

  • 操作系统 CentOS7.7-86_x64
  • 硬件配置:4GB内存,4个CPU,硬盘50GB
  • 集群中所有机器之间网络互通
  • 可以访问外网,需要拉取镜像
  • 禁止swap分区

2. 学习目标

  1. 在所有节点上安装Docker和kubeadm
  2. 部署Kubernetes Master
  3. 部署容器网络插件
  4. 部署 Kubernetes Node,将节点加入Kubernetes集群中
  5. 部署Dashboard Web页面,可视化查看Kubernetes资源

3. 准备环境

关闭防火墙:
$ systemctl stop firewalld
$ systemctl disable firewalld

关闭selinux:
$ sed -i 's/enforcing/disabled/' /etc/selinux/config 
$ setenforce 0

关闭swap:
$ swapoff -a    临时
$ sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab  永久

添加主机名与IP对应关系(记得设置主机名):
$ cat >> /etc/hosts << EOF
9.110.187.20 k8s-master
9.110.187.23 k8s-node1
9.110.187.24 k8s-node2
EOF

将桥接的IPv4流量传递到iptables的链:
$ cat > /etc/sysctl.d/kubernetes.conf << EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
net.ipv4.tcp_tw_recycle=0
vm.swappiness=0
vm.overcommit_memory=1
vm.panic_on_oom=0
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963
fs.nr_open=52706963
net.ipv6.conf.all.disable_ipv6=1
net.netfilter.nf_conntrack_max=2310720
EOF

$ sysctl -p /etc/sysctl.d/kubernetes.conf

时间同步:

$ yum install ntpdate -y
$ ntpdate time.windows.com
$ echo "time.windows.com" >> /etc/rc.d/rc.local
$ chmod +x /etc/rc.d/rc.local

4. 所有节点安装Docker/kubeadm/kubelet

4.1 安装Docker

$ wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
$ yum -y install docker-ce-18.06.1.ce-3.el7    #指定版本安装
$ systemctl enable docker && systemctl start docker
$ docker --version
Docker version 18.06.1-ce, build e68fc7a

$ cat > /etc/docker/daemon.json << EOF
{
  "registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"],
 # "insecure-registries": ["9.110.187.200"],    # 内网镜像仓库
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2"
}
EOF

$ systemctl start docker && systemctl enable docker

4.2 添加阿里云YUM软件源

$ cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

4.3 安装kubeadm,kubelet和kubectl

指定版本号部署:

$ yum install -y kubelet-1.17.0 kubeadm-1.17.0 kubectl-1.17.0 
$ systemctl enable kubelet

5. 部署Kubernetes Master

在192.168.31.63(Master)执行。

$ kubeadm init \
  --apiserver-advertise-address=9.110.187.20 \
  --image-repository registry.aliyuncs.com/google_containers \
  --kubernetes-version v1.17.0 \
  --service-cidr=10.96.0.0/12 \
  --pod-network-cidr=10.244.0.0/16

由于默认拉取镜像地址k8s.gcr.io国内无法访问,这里指定阿里云镜像仓库地址。

使用kubectl工具:

$ mkdir -p $HOME/.kube
$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
$ sudo chown $(id -u):$(id -g) $HOME/.kube/config
$ kubectl get nodes

kubectl自动补全
# yum -y install bash-completion 
$ source <(kubectl completion bash)
$ echo "source <(kubectl completion bash)" >> ~/.bashrc

6. 安装Pod网络插件(CNI)

$ kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/a70459be0084506e4ec919aa1c114638878db11b/Documentation/kube-flannel.yml

确保能够访问到quay.io这个registery。

如果下载失败,可以改成这个镜像地址:lizhenliang/flannel:v0.11.0-amd64

7. 加入Kubernetes Node

在9.110.187.23/24(Node)执行。

向集群添加新节点,执行在kubeadm init输出的kubeadm join命令:

$ kubeadm join 9.110.187.20:6443 --token vbuwrx.cebhdl5aasy2072f \
>     --discovery-token-ca-cert-hash sha256:960cfddc695e71edcc7c2ea3b3def734f737ec15d357c1382d5dda362fe37f21

8. 测试kubernetes集群

在Kubernetes集群中创建一个pod,验证是否正常运行:

$ kubectl create deployment nginx --image=nginx
$ kubectl expose deployment nginx --port=80 --type=NodePort
$ kubectl get pod,svc

9. 部署 Dashboard

$ wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta5/aio/deploy/recommended.yaml

修改recommended.yaml文件内容(vi recommended.yaml):

    #增加直接访问端口
    kind: Service
    apiVersion: v1
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
      name: kubernetes-dashboard
      namespace: kubernetes-dashboard
    spec:
      type: NodePort #增加
      ports:
        - port: 443
          targetPort: 8443
          nodePort: 30001 #增加
      selector:
        k8s-app: kubernetes-dashboard

    #因为自动生成的证书很多浏览器无法使用,所以我们自己创建,注释掉kubernetes-dashboard-certs对象声明
    #apiVersion: v1
    #kind: Secret
    #metadata:
    #  labels:
    #    k8s-app: kubernetes-dashboard
    #  name: kubernetes-dashboard-certs
    #  namespace: kubernetes-dashboard
    #type: Opaque
####创建证书

$ mkdir dashboard-certs
$ cd dashboard-certs/

#创建命名空间

$ kubectl create namespace kubernetes-dashboard    #yaml里会自动创建,可以不用单独创建
 
# 创建key文件
$ openssl genrsa -out dashboard.key 2048
    
#证书请求
$ openssl req -days 36000 -new -out dashboard.csr -key dashboard.key -subj '/CN=dashboard-cert'
    
#自签证书
$ openssl x509 -req -in dashboard.csr -signkey dashboard.key -out dashboard.crt
    
#创建kubernetes-dashboard-certs对象
$ kubectl create secret generic kubernetes-dashboard-certs --from-file=dashboard.key --from-file=dashboard.crt -n kubernetes-dashboard

部署Dashboard

 涉及到的两个镜像可以先下载下来
#安装
$ kubectl create -f  ~/recommended.yaml
#检查结果
$ kubectl get pods -A  -o wide
    
$ kubectl get service -n kubernetes-dashboard  -o wide

9.创建dashboard管理员

$ cat >> dashboard-admin.yaml<<EOF
    apiVersion: v1
    kind: ServiceAccount
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
      name: dashboard-admin
      namespace: kubernetes-dashboard
    EOF
    
$ kubectl create -f dashboard-admin.yaml
    
    为用户分配权限:
$ cat >>dashboard-admin-bind-cluster-role.yaml<<EOF
    apiVersion: rbac.authorization.k8s.io/v1
    kind: ClusterRoleBinding
    metadata:
      name: dashboard-admin-bind-cluster-role
      labels:
        k8s-app: kubernetes-dashboard
    roleRef:
      apiGroup: rbac.authorization.k8s.io
      kind: ClusterRole
      name: cluster-admin
    subjects:
    - kind: ServiceAccount
      name: dashboard-admin
      namespace: kubernetes-dashboard
    EOF
    
$ kubectl create -f dashboard-admin-bind-cluster-role.yaml

访问地址:http://NodeIP:30001

创建service account并绑定默认cluster-admin管理员集群角色:

$ kubectl create serviceaccount dashboard-admin -n kube-system
$ kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
$ kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')

使用输出的token登录Dashboard。

10.安装metrics-server

在Node1/Node2上下载镜像文件:

$ docker pull bluersw/metrics-server-amd64:v0.3.6
$ docker tag bluersw/metrics-server-amd64:v0.3.6 k8s.gcr.io/metrics-server-amd64:v0.3.6  

在Master上执行安装:

$ git clone https://github.com/kubernetes-incubator/metrics-server.git
$ cd /metrics-server/deploy/kubernetes

修改metrics-server-deployment.yaml

spec:
      hostNetwork: true     # 新增
      serviceAccountName: metrics-server
      volumes:
      # mount in tmp so we can safely use from-scratch images and/or read-only containers
      - name: tmp-dir
        emptyDir: {}
      containers:
      - name: metrics-server
        image: k8s.gcr.io/metrics-server-amd64:v0.3.6
        args:
          - --cert-dir=/tmp
          - --secure-port=4443
          - --kubelet-insecure-tls          # 新增
          - --kubelet-preferred-address-types=InternalIP,Hostname,InternalDNS,ExternalDNS,ExternalIP  # 新增
        imagePullPolicy: IfNotPresent    # 修改

$ kubectl create -f .

如果不能不能FQ拉取不到镜像可以更改image: registry.cn-hangzhou.aliyuncs.com/google_containers/metrics-server-amd64:v0.3.6

参考李振良老师的博客:https://blog.51cto.com/lizhenliang/2296100


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