正文

kubernetes（k8s）centos7和8快速部署(代码片段)

养了一只皮卡丘  养了一只皮卡丘  2023-03-01  796

关键词：

Kubernetes快速部署

kubeadm是官方社区推出的一个用于快速部署kubernetes集群的工具。

这个工具能通过两条指令完成一个kubernetes集群的部署：

# 创建一个 Master 节点
$ kubeadm init

# 将一个 Node 节点加入到当前集群中
$ kubeadm join <Master节点的IP和端口>

1. 安装要求

在开始之前，部署Kubernetes集群机器需要满足以下几个条件：

-至少3台机器，操作系统 CentOS7+

硬件配置：2GB或更多RAM，2个CPU或更多CPU，硬盘20GB或更多
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

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

3. 准备环境

ps：建议三台centos7，我用kubeletv1.23.1也做出来了。虽然kubeadm源是7，
也可以用三台centos8，kubeletv1.20.0稳定版（最新版可安装不一定能运行）
环境：三台centos7

角色	IP	配置
master	192.168.143.140	2G 4核
node1	192.168.143.141	3G 4核
node2	192.168.143.142	3G 4核

//给三台主机修改名字
[root@master ~]# hostname
master.example.com
[root@node1 ~]# hostname
node1.example.com
[root@node2 ~]# hostname
node2.example.com

//给三台主机关闭防火墙，selinux
systemctl disable  firewalld
sed -i 's/enforcing/disabled/' /etc/selinux/config  

//给三台主机关闭swap：
vim /etc/fstab
#/dev/mapper/centos-swap swap                    swap    defaults        0 0
注释掉swap分区


在master添加hosts：
[root@master ~]# vim /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
//后面添加此三行
192.168.143.140 master master.example.com
192.168.143.141 node1 node1.example.com
192.168.143.142 node2 node2.example.com


//将桥接的IPv4流量传递到iptables的链：
[root@master ~]# cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
//生效
[root@master ~]# sysctl --system
* Applying /usr/lib/sysctl.d/00-system.conf ...
* Applying /usr/lib/sysctl.d/10-default-yama-scope.conf ...
kernel.yama.ptrace_scope = 0
* Applying /usr/lib/sysctl.d/50-default.conf ...
kernel.sysrq = 16
kernel.core_uses_pid = 1
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.default.promote_secondaries = 1
net.ipv4.conf.all.promote_secondaries = 1
fs.protected_hardlinks = 1
fs.protected_symlinks = 1
* Applying /etc/sysctl.d/99-sysctl.conf ...
* Applying /etc/sysctl.d/k8s.conf ...
* Applying /etc/sysctl.conf ...

//给三台主机做时间同步：
yum -y install chrony
vim /etc/chrony.conf 
pool time1.aliyun.com iburst //时间同步删除原有的4条，修改为此行
systemctl enable  chronyd

//免密认证：
[root@master ~]# ssh-keygen -t rsa
[root@master ~]# ssh-copy-id master
[root@master ~]# ssh-copy-id node1
[root@master ~]# ssh-copy-id node2

//检查状态
[root@master ~]# for i in  node1 node2 master;do ssh root@$i 'reboot';done
[root@master ~]# for i in master node1 node2;do ssh root@$i 'getenforce';done
Disabled
Disabled
Disabled
[root@master ~]# for i in master node1 node2;do ssh root@$i 'date';done
[root@master ~]# for i in master node1 node2;do ssh root@$i 'free -h';done
              total        used        free      shared  buff/cache   available
Mem:           1.8G        105M        1.5G        9.6M        197M        1.5G
Swap:            0B          0B          0B
              total        used        free      shared  buff/cache   available
Mem:           2.8G        108M        2.5G        9.4M        194M        2.5G
Swap:            0B          0B          0B
              total        used        free      shared  buff/cache   available
Mem:           2.8G        111M        2.5G        9.4M        194M        2.5G
Swap:            0B          0B          0B

4. 所有节点安装Docker/kubeadm/kubelet

Kubernetes默认CRI（容器运行时）为Docker，因此先安装Docker。

4.1 配置kubeadm源安装Docker

//给三台主机配置kubeadm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

//给三台主机做docker源
# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
//建立缓存
# rm -rf /var/cache/yum/*
# yum makecache
//给三台主机配置docker-ce
# yum install -y docker-ce
# systemctl enable --now docker
# cat > /etc/docker/daemon.json << EOF

  "registry-mirrors": ["https://docker.mirrors.ustc.edu.cn/"],
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": 
    "max-size": "100m"
  ,
  "storage-driver": "overlay2"

EOF
# systemctl daemon-reload 
# systemctl restart docker
# docker info //查看有无配置

4.2 安装kubeadm，kubelet和kubectl

//不指定版本为最新版本，也可以使用
由于版本更新频繁，这里指定版本号部署：

//给三台主机做
# yum install -y kubelet-1.20.0 kubeadm-1.20.0 kubectl-1.20.0
# systemctl enable kubelet

5. 部署Kubernetes Master

在Master执行。

//注意 ip是master的 。version是kuber的版本。可以变
[root@master ~]# kubeadm init --apiserver-advertise-address 192.168.143.140 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.20.0 --service-cidr=10.96.0.0/12 --pod-network-cidr=10.244.0.0/16
//存储信息。此行内容是。init完成后产生后，最后一行数据，添加集群时要用到。
[root@master ~]# vi init 
kubeadm join 192.168.143.140:6443 --token arkgcf.smaj7konv41yifxd \\
    --discovery-token-ca-cert-hash sha256:30e1b03d7112abc8ed8b84bf0c69ef4bdb3498911ac468f3a2c7887bdd38918c  
[root@master ~]# echo 'export KUBECONFIG=/etc/kubernetes/admin.conf' > /etc/profile.d/k8s.sh
[root@master ~]# source /etc/profile.d/k8s.sh

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。

//普通用户要做的事，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

6. 安装Pod网络插件（CNI）

[root@master ~]# vim flannel.yaml 
---
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
  name: psp.flannel.unprivileged
  annotations:
    seccomp.security.alpha.kubernetes.io/allowedProfileNames: docker/default
    seccomp.security.alpha.kubernetes.io/defaultProfileName: docker/default
    apparmor.security.beta.kubernetes.io/allowedProfileNames: runtime/default
    apparmor.security.beta.kubernetes.io/defaultProfileName: runtime/default
spec:
  privileged: false
  volumes:
  - configMap
  - secret
  - emptyDir
  - hostPath
  allowedHostPaths:
  - pathPrefix: "/etc/cni/net.d"
  - pathPrefix: "/etc/kube-flannel"
  - pathPrefix: "/run/flannel"
  readOnlyRootFilesystem: false
  # Users and groups
  runAsUser:
    rule: RunAsAny
  supplementalGroups:
    rule: RunAsAny
  fsGroup:
    rule: RunAsAny
  # Privilege Escalation
  allowPrivilegeEscalation: false
  defaultAllowPrivilegeEscalation: false
  # Capabilities
  allowedCapabilities: ['NET_ADMIN', 'NET_RAW']
  defaultAddCapabilities: []
  requiredDropCapabilities: []
  # Host namespaces
  hostPID: false
  hostIPC: false
  hostNetwork: true
  hostPorts:
  - min: 0
    max: 65535
  # SELinux
  seLinux:
    # SELinux is unused in CaaSP
    rule: 'RunAsAny'
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
rules:
- apiGroups: ['extensions']
  resources: ['podsecuritypolicies']
  verbs: ['use']
  resourceNames: ['psp.flannel.unprivileged']
- apiGroups:
  - ""
  resources:
  - pods
  verbs:
  - get
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes/status
  verbs:
  - patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: flannel
subjects:
- kind: ServiceAccount
  name: flannel
  namespace: kube-system
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: flannel
  namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: kube-flannel-cfg
  namespace: kube-system
  labels:
    tier: node
    app: flannel
data:
  cni-conf.json: |
    
      "name": "cbr0",
      "cniVersion": "0.3.1",
      "plugins": [
        
          "type": "flannel",
          "delegate": 
            "hairpinMode": true,
            "isDefaultGateway": true
          
        ,
        
          "type": "portmap",
          "capabilities": 
            "portMappings": true
          
        
      ]
    
  net-conf.json: |
    
      "Network": "10.244.0.0/16",
      "Backend": 
        "Type": "vxlan"
      
    
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: kube-flannel-ds
  namespace: kube-system
  labels:
    tier: node
    app: flannel
spec:
  selector:
    matchLabels:
      app: flannel
  template:
    metadata:
      labels:
        tier: node
        app: flannel
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: kubernetes.io/os
                operator: In
                values:
                - linux
      hostNetwork: true
      priorityClassName: system-node-critical
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni-plugin
        image: rancher/mirrored-flannelcni-flannel-cni-plugin:v1.0.0
        command:
        - cp
        args:
        - -f
        - /flannel
        - /opt/cni/bin/flannel
        volumeMounts:
        - name: cni-plugin
          mountPath: /opt/cni/bin
      - name: install-cni
        image: quay.io/coreos/flannel:v0.15.1
        command:
        - cp
        args:
        - -f
        - /etc/kube-flannel/cni-conf.json
        - /etc/cni/net.d/10-flannel.conflist
        volumeMounts:
        - name: cni
          mountPath: /etc/cni/net.d
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      containers:
      - name: kube-flannel
        image: quay.io/coreos/flannel:v0.15.1
        command:
        - /opt/bin/flanneld
        args:
        - --ip-masq
        - --kube-subnet-mgr
        resources:
          requests:
            cpu: "100m"
            memory: "50Mi"
          limits:
            cpu: "100m"
            memory: "50Mi"
        securityContext:
          privileged: false
          capabilities:
            add: ["NET_ADMIN", "NET_RAW"]
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        volumeMounts:
        - name: run
          mountPath: /run/flannel
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      volumes:
      - name: run
        hostPath:
          path: /run/flannel
      - name: cni-plugin
        hostPath:
          path: /opt/cni/bin
      - name: cni
        hostPath:
          path: /etc/cni/net.d
      - name: flannel-cfg
        configMap:
          name: kube-flannel-cfg
[root@master ~]# kubectl apply -f flannel.yaml

确保能够访问到quay.io这个registery。

7. 加入Kubernetes Node

在node1 和node2执行。

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

kubeadm join 192.168.143.140:6443 --token arkgcf.smaj7konv41yifxd \\
>     --discovery-token-ca-cert-hash sha256:30e1b03d7112abc8ed8b84bf0c69ef4bdb3498911ac468f3a2c7887bdd38918c

8. 测试kubernetes集群

在Kubernetes集群中创建一个pod，验证是否正常运行：

[root@master ~]# kubectl get nodes
NAME                 STATUS   ROLES                  AGE     VERSION
master.example.com   Ready    control-plane,master   21m     v1.20.0
node1.example.com    Ready    <none>                 5m44s   v1.20.0
node2.example.com    Ready    <none>                 5m39s   v1.20.0

[root@master ~]# kubectl create deployment nginx --image=nginx
deployment.apps/nginx created
[root@master ~]# kubectl expose deployment nginx --port=80 --type=NodePort
service/nginx exposed

//获取svc，pods的信息
[root@master ~]# kubectl get svc,pods
NAME                 TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE
service/kubernetes   ClusterIP   10.96.0.1        <none>        443/TCP        28m
service/nginx        NodePort    10.109.147.208   <none>        80:32432/TCP   5m20s

NAME                         READY   STATUS    RESTARTS   AGE
pod/nginx-6799fc88d8-wk29t   1/1     Running   0          6m18s

//测试主机ip访问
[root@master ~]# curl 192.168.143.140:32432
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html  color-scheme: light dark; 
body  width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; 
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>
//建议使用server的ip来访问，因为不会改变
[root@master ~]# curl 10.109.147.208
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html  color-scheme: light dark; 
body  width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; 
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>

<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>

<p><em>Thank you for using nginx.</em></p>
</body>
</html>

访问地址：http://NodeIP:Port

认识kubernetes（k8s）(代码片段)

目录一、Kubernetes简介2.为什么要用Kubernetes3.Kubernetes解决的问题二、k8s特点1、自动装箱2、自我修复3、弹性伸缩4、自动部署和回滚5、服务发现和负载均衡6、机密和配置管理7、存储编排8、任务批处理运行三、Kubernetes集群架构与... 查看详情

云原生训练营模块四kubernetes架构原则和对象设计(代码片段)

Kubernetes架构原则和对象设计K8s安装K8s概念K8s架构控制器的工作流程了解KubectlKubernetes生态系统常用Kubernetes对象及其分组核心技术概念和API对象TypeMeta核心对象概览课后练习K8s安装CentOS7利用Kubeadm快速部署Kubernetes集群K8s概念Kubernete... 查看详情

云原生|kubernetes篇深入kubernetes（k8s）概念(代码片段)

文章目录深入Kubernetes（k8s）概念一、基础概念理解二、kubernetesObjects（k8s对象）1、什么是k8s对象2、描述k8s对象3、k8s对象yaml的结构4、管理k8s对象5、对象名称6、名称空间7、标签和选择器8、注解annotation9、字段选... 查看详情

kubernetes学习笔记——k8s概念和架构

突然想了解一下k8s(kubernetes，是因为取第1个和最后1个字母，中间有8个字母，所以叫k8s)，以此系列文章记录一下，分享给大家，也便于后期自己复习查看。参考视频：哔哩哔哩K8S教程由浅入深-尚硅谷K8S... 查看详情

kubernetes学习笔记——k8s概念和架构

k8s的基础概念

一、Kubernetes介绍1、什么是Kubernetes？Kubernetes(通常称为K8s，K8s是将8个字母“ubernete”替换为“8”的缩写)是一个以容器为中心的基础架构，可以实现在物理集群或虚拟机集群上调度和运行容器，提供容器自动部署、扩展和管理的... 查看详情

k8s1.8.2部署实践(代码片段)

...服务的注册和发现集群，每个节点都可以提供服务。2，kubernetes系统组件间只能通过API服务器通信，它们之间不会直接通信，API服务器是和etcd通信的唯一组件。其他组件不会直接和etcd通信，需要通过API服务器来修改集群状态。3... 查看详情

kubernetes(k8s)笔记总结(代码片段)

文章目录1.云平台2.私有网络VPC(重点！！！)3.Kubernetes介绍4.k8s架构5.kubectl和kubeadm6.三台云服务器的安装部署7.Kubernetes环境搭建7.1安装docker环境7.2安装k8s的预备环境8.kubernetes集群安装的三大件(kubelet、kubeadm、kubectl)9.kubern... 查看详情

超详细部署kubernetes教程

Kubeadm部署k8s单点master1、环境准备：主机名IP说明宿主机系统master10.0.0.17Kubernetes集群的master节点CentOS7.9node110.0.0.27Kubernetes集群的node节点CentOS7.9#所有master和node节点执行：#关闭防火墙、iptables和selinuxsystemctlstopfirewalld&& 查看详情

k8s------kubernetes概述(代码片段)

目录一.Kubernetes概述1.Kubernetes概念2.为什么要用Kubernetes3.Kubernetes解决的问题4.Kubernetes的特性二.Kubernetes集群架构与组件1.核心组件①Master组件Kube-apiserverKube-controller-managerKube-scheduler②配置存储中心etcd③Node组件KubeletKube-Proxydocker或ro... 查看详情

kubernetes概述和kubeadm方式集群搭建(代码片段)

kubernetes概述和kubeadm方式集群搭建kubernetes概述k8s的功能K8S集群架构组件K8S核心概念集群搭建kubeadm部署方式1.系统初始化2.master和node1,2安装Docker/kubeadm/kubelet3.部署KubernetesMaster4.加入KubernetesNode5.安装Pod网络插件（CNI）6.测试ku... 查看详情

docker与k8s的恩怨情仇——kubernetes的创新

...xff0c;赋能开发者。上节中我们提到了社区生态的发展使得Kubernetes得到了良性的发展和传播。比起相对封闭的Docker社区开放的CNCF社区获得了更大成功，但仅仅是社区的活力对比还不足以让Docker这么快的败下阵来，其根本原... 查看详情

k8s集群搭建(代码片段)

...操作实例:"　　　01,配置yum源cat<<EOF>/etc/yum.repos.d/kubernetes.repo[kubernetes]name=Kubernetesbaseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64enabled=1gpgcheck=0repo_gpgcheck=0gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpghttp://mirro... 查看详情

2.docker和k8s(kubernetes)有啥关系

参考技术A首先看看k8s[中间8个字母，数过了(逃](Kubernetes)是什么以及为啥会出现这个东西。总的来说，k8s的出现和使用容器进行部署的趋势是分不开的。总的来说，app的部署大致分为三个阶段。最传统的方式中，所有app公用一个... 查看详情

centos7.8部署docker

1.通过CentOS安装Docker1.1查看操作系统平台[root@k8s~]#cat/etc/redhat-releaseCentOSLinuxrelease7.8.2003(Core)[root@k8s~]#uname-r3.10.0-1127.el7.x86_64[root@k8s~]#uname-mx86_641.2安装相关依赖环境[root@k8s~]#yum-yinstallyum- 查看详情

centos7部署k8s集群

前期准备systemctlstopfirewalldsystemctldisablefirewalldyum-yinstallntpsystemctlstartntpdsystemctlenablentpdyumupdate-y 安装etcd Kubernetes yum-yinstalletcdkubernetes flannel 配查看详情

k8s1.23.8安装kubegems管理界面(代码片段)

标签（空格分隔）：kubernetes系列一：kubegems的介绍1.1kubegems介绍：KubeGems是一款以围绕Kubernetes通过自研和集成云原生项目而构建的通用性开源PaaS云管理平台。经过近一年的持续迭代，当前KubeGems的核心功能已经初步具备多云多租... 查看详情

kubernetes和docker关系简单说明

参考技术A最近项目用到kubernetes（以下简称k8s，k和s之间有8个字母)。虽然之前也有简单使用过，但最近发现k8s概念较多，命令也有些不够用了，故想借此机会写点东西，更全面认识并使用k8s。本篇文章目的：让你更全面了解k8s概... 查看详情