从0-1快速搭建一个k8s集群（一主多从）

其他 2020-01-11 10:18:05 阅读次数: 0

前言

       Kubernetes是一个为用户提供具有普遍意义的容器编排工具。能够按照用户的意愿和整个系统的规则，完全自动化地处理好容器之间的各种关系。同时，能提供一套基于容器构建分布式系统的基础依赖。下面就以Kubernetes1.15.3为例，带领大家从0到1搭建一个完整的Kubernetes集群。该集群基于kubeadm的方式搭建，应用节点具有高可用。

（一）服务器准备

1. Linux版本：CentOS 7.5

通过 cat /etc/redhat-release 列出版本信息。

2. 准备三个节点

需要一个主节点，至少两个从节点。

3. 主节点的配置要求

需要有2个CPU，至少2G内存。

4.k8s版本

本次k8s部署的版本为1.15.3。

（二）环境预安装（所有节点均需要安装）

1. 更换yum源

<1> 新建文件Centos-7.repo，内容如下：

# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client.  You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the 
# remarked out baseurl= line instead.
#
#
 
[base]
name=CentOS-$releasever - Base - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/os/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/os/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#released updates 
[updates]
name=CentOS-$releasever - Updates - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/updates/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/updates/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/extras/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/extras/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/centosplus/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/centosplus/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#contrib - packages by Centos Users
[contrib]
name=CentOS-$releasever - Contrib - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/contrib/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/contrib/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

<2> 将 Centos-7.repo 放到 /etc/yum.repos.d/ 里面去。

2. 关闭swap分区

<1> 查看分区情况

通过 free -m 查看分区情况，此时分区已打开；

<2> 关闭分区

vim /etc/fstab，将swap的那一行注释（用#号注释）。

保存，退出。

<3> 重启

通过reboot重启服务器，最后用free -m验证。

此时swap都为0，证明swap分区已关闭。

3. 关闭防火墙

通过 systemctl disable firewalld 关闭防火墙，然后 systemctl status firewalld 查看防火墙状态

4. 修改hostname

执行hostname XXX。

比如hostname zz-node-1，修改主机名为zz-node-1。

5.  同步时间

通过 ntpdate 0.asia.pool.ntp.org 同步时间。同步完成后，通过 date 查看时间。

注意：如果有时间同步服务，也可以与它同步，具体步骤（假设时间同步服务地址为：10.0.18.253）：

通过 crontab -e 命令，输入如下内容并保存：

*/1 * * * * /usr/sbin/ntpdate 10.0.18.253

通过 crontab -l 命令查看是否生效。

6. docker安装

参考链接：https://blog.csdn.net/li1325169021/article/details/90780627

7. kubeadm安装

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

# 将 SELinux 设置为 permissive 模式(将其禁用)
setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config

yum install -y kubelet-1.15.3 kubeadm-1.15.3 kubectl-1.15.3 --disableexcludes=kubernetes

systemctl enable kubelet && systemctl start kubelet

8. 拉取k8s镜像

本文以Kubernetes1.16.3版本为例。在安装部署中，需要从k8s.grc.io仓库中拉取所需镜像文件，而该仓库需要翻墙才能正常拉取，因此需要解决从k8s.gcr.io拉取镜像失败问题。可以通过手动从能获取到镜像的仓库拉取镜像，并改名的方式来解决。

<1> 通过docker.io仓库拉取k8镜像

docker pull mirrorgooglecontainers/kube-apiserver-amd64:v1.15.3
docker pull mirrorgooglecontainers/kube-controller-manager-amd64:v1.15.3
docker pull mirrorgooglecontainers/kube-scheduler-amd64:v1.15.3
docker pull mirrorgooglecontainers/kube-proxy-amd64:v1.15.3
docker pull mirrorgooglecontainers/pause:3.1
docker pull mirrorgooglecontainers/etcd-amd64:3.3.10
docker pull coredns/coredns:1.3.1

上面的版本可以根据部署的需要修改。

<2> 通过 docker tag 命令修改镜像标签

docker tag docker.io/mirrorgooglecontainers/kube-proxy-amd64:v1.15.3 k8s.gcr.io/kube-proxy:v1.15.3
docker tag docker.io/mirrorgooglecontainers/kube-scheduler-amd64:v1.15.3 k8s.gcr.io/kube-scheduler:v1.15.3
docker tag docker.io/mirrorgooglecontainers/kube-apiserver-amd64:v1.15.3 k8s.gcr.io/kube-apiserver:v1.15.3
docker tag docker.io/mirrorgooglecontainers/kube-controller-manager-amd64:v1.15.3 k8s.gcr.io/kube-controller-manager:v1.15.3
docker tag docker.io/mirrorgooglecontainers/etcd-amd64:3.3.10  k8s.gcr.io/etcd:3.3.10
docker tag docker.io/mirrorgooglecontainers/pause:3.1  k8s.gcr.io/pause:3.1
docker tag coredns/coredns:1.3.1  k8s.gcr.io/coredns:1.3.1

（三）安装k8s集群

  • 安装主节点

1. 初始化k8s集群

<1> 通过 kubeadm init 命令初始化k8s集群

kubeadm init --kubernetes-version=v1.15.3

初始化成功的结果如下所示：

<2> 按照初始化完成提示，初始化配置

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

并保存 kubeadm join 的提示信息：

kubeadm join 10.0.112.63:6443 --token peuyuz.swqrjk30wlqlyg47 \
    --discovery-token-ca-cert-hash sha256:4f05d1c2f9877112a37bad18355f246afc304b593666290f09fbdd5761d09bf6

2. 部署网络插件

kubectl apply -f https://git.io/weave-kube-1.6

3. 通过 kubectl get nodes 查看主节点状态

可以看到STATUS状态为Ready，证明k8s集群初始化成功。

  • 安装从节点

1. 加入k8s集群

执行上面保存的kubeadm join。

2. 通过 kubectl get nodes 查看节点状态

如果STATUS状态都为Ready，证明集群安装成功

（四）部署Rook插件

插件下载地址：https://github.com/rook/rook/tree/release-1.0

拷贝cluster/examples/kubernetes/ceph下的common.yaml，operator.yaml，cluster.yaml到主节点上，然后执行如下命令：

kubectl apply -f common.yaml

kubectl apply -f operator.yaml

kubectl apply -f cluster.yaml

通过 kubectl get pods -n rook-ceph 查看部署情况：

如图所示，证明部署成功。

（五）部署Dashboard

1. 镜像拉取

拉取 kubernetes-dashboard（1.8.3）的镜像。

docker pull docker.io/siriuszg/kubernetes-dashboard-amd64:v1.8.3

2. 新增 kubernetes-dashboard.yaml 文件

新增kubernetes-dashboard.yaml文件，并输入如下内容：

# Copyright 2017 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Configuration to deploy release version of the Dashboard UI compatible with
# Kubernetes 1.8.
#
# Example usage: kubectl create -f <this_file>

# ------------------- Dashboard Secret ------------------- #

apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-certs
  namespace: kube-system
type: Opaque

---
# ------------------- Dashboard Service Account ------------------- #

apiVersion: v1
kind: ServiceAccount
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system

---
# ------------------- Dashboard Role & Role Binding ------------------- #

kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: kubernetes-dashboard-minimal
  namespace: kube-system
rules:
  # Allow Dashboard to create 'kubernetes-dashboard-key-holder' secret.
- apiGroups: [""]
  resources: ["secrets"]
  verbs: ["create"]
  # Allow Dashboard to create 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
  resources: ["configmaps"]
  verbs: ["create"]
  # Allow Dashboard to get, update and delete Dashboard exclusive secrets.
- apiGroups: [""]
  resources: ["secrets"]
  resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs"]
  verbs: ["get", "update", "delete"]
  # Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
  resources: ["configmaps"]
  resourceNames: ["kubernetes-dashboard-settings"]
  verbs: ["get", "update"]
  # Allow Dashboard to get metrics from heapster.
- apiGroups: [""]
  resources: ["services"]
  resourceNames: ["heapster"]
  verbs: ["proxy"]
- apiGroups: [""]
  resources: ["services/proxy"]
  resourceNames: ["heapster", "http:heapster:", "https:heapster:"]
  verbs: ["get"]

---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: kubernetes-dashboard-minimal
  namespace: kube-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: kubernetes-dashboard-minimal
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard
  namespace: kube-system

---
# ------------------- Dashboard Deployment ------------------- #

kind: Deployment
apiVersion: apps/v1beta2
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
spec:
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kubernetes-dashboard
  template:
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
    spec:
      containers:
      - name: kubernetes-dashboard
        image: docker.io/siriuszg/kubernetes-dashboard-amd64:v1.8.3
        ports:
        - containerPort: 8443
          protocol: TCP
        args:
          - --auto-generate-certificates
          # Uncomment the following line to manually specify Kubernetes API server Host
          # If not specified, Dashboard will attempt to auto discover the API server and connect
          # to it. Uncomment only if the default does not work.
          # - --apiserver-host=http://my-address:port
        volumeMounts:
        - name: kubernetes-dashboard-certs
          mountPath: /certs
          # Create on-disk volume to store exec logs
        - mountPath: /tmp
          name: tmp-volume
        livenessProbe:
          httpGet:
            scheme: HTTPS
            path: /
            port: 8443
          initialDelaySeconds: 30
          timeoutSeconds: 30
      volumes:
      - name: kubernetes-dashboard-certs
        secret:
          secretName: kubernetes-dashboard-certs
      - name: tmp-volume
        emptyDir: {}
      serviceAccountName: kubernetes-dashboard
      # Comment the following tolerations if Dashboard must not be deployed on master
      tolerations:
      - key: node-role.kubernetes.io/master
        effect: NoSchedule

---
# ------------------- Dashboard Service ------------------- #

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
spec:
  ports:
    - port: 443
      targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard

3. 执行kubectl apply

通过 kubectl apply 命令，生成pod对象。

kubectl apply -f kubernetes-dashboard.yaml

4. 配置代理

<1> 通过 kubectl proxy 启动代理

nohup kubectl proxy --address='0.0.0.0' --accept-hosts='^*$' &

其中nohup表示后台运行。

<2> 验证

访问如下URL验证：

http://主节点IP:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy

看到这个界面，很开心，因为仪表板已经成功启动了。

5. 配置权限

<1> 新增 dashboard-admin.yml 文件

通过 vim dashboard-admin.yml 命令，输入以下内容并保存：

apiVersion: rbac.authorization.k8s.io/v1beta1

kind: ClusterRoleBinding

metadata:

name: kubernetes-dashboard

labels:

k8s-app: kubernetes-dashboard

roleRef:

apiGroup: rbac.authorization.k8s.io

kind: ClusterRole

name: cluster-admin

subjects:

- kind: ServiceAccount

name: kubernetes-dashboard

namespace: kube-system

<2> 执行 kubectl apply

通过 kubectl apply 命令生成对象。

kubectl apply -f dashboard-admin.yml

<3> 验证

在界面上点击跳过

出现如下界面，现在仪表板能正确展示啦！

总结

       本文主要介绍了如何从0到1搭建k8s集群，从下一节开始，我会针对k8s所具有的所有特性，逐一实践。为读者在生产环境部署应用k8s铺路。欢迎继续收看。

参考资料

1. docker与k8s的版本匹配

https://blog.csdn.net/cdbdqn001/article/details/88183777

https://blog.csdn.net/CSDN_duomaomao/article/details/79171027

2. 如何解决从k8s.gcr.io拉取镜像失败问题

https://blog.csdn.net/jinguangliu/article/details/82792617

3. curl : Depends: libcurl3-gnutls (= 7.47.0-1ubuntu2.12) but 7.58.0-2ubuntu3.6 is to be installed

https://blog.csdn.net/wanttifa/article/details/88965082

4. gpg: no valid OpenPGP data found

https://blog.csdn.net/wiborgite/article/details/52840371

5. Kubernetes-kubectl命令出现错误：The connection to the server localhost:8080 was refused - did you specify the right host or port?

https://www.jianshu.com/p/6fa06b9bbf6a

小缘缘
发布了19 篇原创文章 · 获赞 20 · 访问量 5844
私信 关注

猜你喜欢

转载自blog.csdn.net/qq_15898739/article/details/103068981
今日推荐
中国码农的“35岁魔咒”
蘭雅 CorelDRAW 插件 2024.5.1 国际劳动节版，免费下载
Arc Browser for Windows 1.0 正式 GA
90后程序员开发视频搬运软件、不到一年获利超 700 万，结局很刑！
《美国对全球网络空间安全与发展的威胁和破坏》报告发布
周排行
[编程题]学英语
[codeforces 1288A] Deadline 约数+模
Python的web开发
Docker在Centos 7上的部署
python编码
解决Ubuntu16.04 fatal error: json/json.h: No such file or directory
mysql并发插入
rest接口如何适应jsonp的方案
linux 终端上网设置
高数——等号两边同时求导、积分的解释
每日归档
更多
2024-05-04(7)
2024-05-03(19)
2024-05-02(0)
2024-05-01(4)
2024-04-30(1)
2024-04-29(40)
2024-04-28(0)
2024-04-27(56)
2024-04-26(39)
2024-04-25(22)

代码天地 © 2018 codetd.com

境外服务器   最新电视剧2022