目录
3.3 为每台服务器安装kubelet、kubeadm、kubectl
具体操作步骤可以参考之前的教程,建议是先安装一台,然后克隆虚拟机,这样速度快。
注意:在克隆时记得修改Mac地址、IP地址、UUID和主机名。(最后别忘了保存下快照~)
安装VMware虚拟机、Linux系统(CentOS7)_何苏三月的博客-CSDN博客
克隆Linux系统(centos)_linux克隆_何苏三月的博客-CSDN博客

请参考:Docker安装、常见命令、安装常见容器(Mysql、Redis等)_docker redis 容器_何苏三月的博客-CSDN博客
教程中安装docker的命令
yum install docker-ce docker-ce-cli containerd.io
原来是默认安装最新版,这里需要指定一下版本,目的是保障后续安装k8s不出问题:
yum install -y docker-ce-20.10.7 docker-ce-cli-20.10.7 containerd.io-1.4.6
其他步骤不变。
一台兼容的 Linux 主机。Kubernetes 项目为基于 Debian 和 Red Hat 的 Linux 发行版以及一些不提供包管理器的发行版提供通用的指令。
每台机器 2 GB 或更多的 RAM (如果少于这个数字将会影响你应用的运行内存)
2 CPU 核或更多
集群中的所有机器的网络彼此均能相互连接(公网和内网都可以)
设置防火墙放行规则
节点之中不可以有重复的主机名、MAC 地址或 product_uuid。请参见这里了解更多详细信息。
开启机器上的某些端口。请参见这里 了解更多详细信息。
禁用交换分区。为了保证 kubelet 正常工作,你 必须 禁用交换分区。
- #各个机器设置自己的域名
- hostnamectl set-hostname xxxx
-
-
- # 将 SELinux 设置为 permissive 模式(相当于将其禁用)
- sudo setenforce 0
- sudo sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config
-
- #关闭swap
- swapoff -a
- sed -ri 's/.*swap.*/#&/' /etc/fstab
-
- #允许 iptables 检查桥接流量
- cat <<EOF | sudo tee /etc/modules-load.d/k8s.conf
- br_netfilter
- EOF
-
- cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf
- net.bridge.bridge-nf-call-ip6tables = 1
- net.bridge.bridge-nf-call-iptables = 1
- EOF
- sudo sysctl --system



kubelet - “厂长”
kubectl - 程序员敲命令行的命令窗
kubeadm - 引导创建集群的
- # 1.先配置K8S去哪儿下载的地址信息
- cat <<EOF > /etc/yum.repos.d/kubernetes.repo
- [kubernetes]
- name=Kubernetes
- baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
- enabled=1
- gpgcheck=0
- repo_gpgcheck=0
- gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
- http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
- exclude=kubelet kubeadm kubectl
- EOF
- # 2. 安装
- sudo yum install -y kubelet-1.20.9 kubeadm-1.20.9 kubectl-1.20.9 --disableexcludes=kubernetes
- # 3. 启动kubelet
- sudo systemctl enable --now kubelet
💡systemctl status kubelet 查看状态会发现,kubelet 现在每隔几秒就会重启,因为它陷入了一个等待 kubeadm 指令的死循环。这是正常现象不用管!




下载各个机器需要的镜像,以下只需要在master机器上执行:
- # 1. 定义一个for循环,需要的东西下载
- sudo tee ./images.sh <<-'EOF'
- #!/bin/bash
- images=(
- kube-apiserver:v1.20.9
- kube-proxy:v1.20.9
- kube-controller-manager:v1.20.9
- kube-scheduler:v1.20.9
- coredns:1.7.0
- etcd:3.4.13-0
- pause:3.2
- )
- for imageName in ${images[@]} ; do
- docker pull registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images/$imageName
- done
- EOF
- # 2. 赋予权限,让它下载这些东西
- chmod +x ./images.sh && ./images.sh



从图上可以知道,从节点也需要安装kube-proxy。我们可以只下载这个镜像,当然了为了避免出现意外,我们也可以都下载下来。
方法完全参考4.1
1.首先给所有的服务器都添加一下k8s110这台服务器的域名映射
- #所有机器添加master域名映射,以下需要修改为自己的内网ip地址
- echo "192.168.37.110 cluster-endpoint" >> /etc/hosts

2.然后只在k8s110这台服务器上执行主节点初始化过程:
- #主节点初始化
- kubeadm init \
- --apiserver-advertise-address=192.168.37.110 \
- --control-plane-endpoint=cluster-endpoint \
- --image-repository registry.cn-hangzhou.aliyuncs.com/lfy_k8s_images \
- --kubernetes-version v1.20.9 \
- --service-cidr=10.96.0.0/16 \
- --pod-network-cidr=192.168.50.0/24
-
- #要求所有网络范围不重叠 --pod-network-cidr --service-cidr --apiserver-advertise-address 都不能重叠

如果出现上述错误,则执行如下命令:
sysctl -w net.ipv4.ip_forward=1

然后重新执行

最后看到如下画面则表示初始化成功!

这段还比较重要的,它告诉我们怎么使用这个集群信息等等,所以我们把文本单独复制出来
- Your Kubernetes control-plane has initialized successfully!
-
- To start using your cluster, you need to run the following as a regular user:
-
- mkdir -p $HOME/.kube
- sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
- sudo chown $(id -u):$(id -g) $HOME/.kube/config
-
- Alternatively, if you are the root user, you can run:
-
- export KUBECONFIG=/etc/kubernetes/admin.conf
-
- You should now deploy a pod network to the cluster.
- Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
- https://kubernetes.io/docs/concepts/cluster-administration/addons/
-
- You can now join any number of control-plane nodes by copying certificate authorities
- and service account keys on each node and then running the following as root:
-
- kubeadm join cluster-endpoint:6443 --token 3e54se.alzs9d1mkf30f25w \
- --discovery-token-ca-cert-hash sha256:689c076e294bdbb588103a51aaa7248b8a0df34bde634a6189d311ad46a02856 \
- --control-plane
-
- Then you can join any number of worker nodes by running the following on each as root:
-
- kubeadm join cluster-endpoint:6443 --token 3e54se.alzs9d1mkf30f25w \
- --discovery-token-ca-cert-hash sha256:689c076e294bdbb588103a51aaa7248b8a0df34bde634a6189d311ad46a02856
那么按照它的要求一步一步执行吧!
3.按要求创建文件夹复制文件给予权限等操作
- mkdir -p $HOME/.kube
- sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
- sudo chown $(id -u):$(id -g) $HOME/.kube/config

然后我们查看一下集群的所有结点:
- #查看集群所有节点
- kubectl get nodes

发现k8s110这台服务器就是master节点了,但是它的状态是NotReady。
没关系按照它的要求继续执行,下一步说需要安装一个网络插件。
4.安装网络插件
可以有多种安装选择,我们就用calico
curl https://docs.projectcalico.org/v3.20/manifests/calico.yaml -O

下载成功,我们calico.yaml配置文件就有了。
重要提示💡:如果我们在初始化主节点时,修改了--pod-network-cidr=192.168.0.0/16,那么我们就要进入这个配置文件,将我们修改后的ip地址写上去。

ok,有了这个配置文件,就可以通过如下命令为k8s安装calico插件所需要的东西了
- #根据配置文件,给集群创建资源(以后通过该命令为k8s创建资源,不限于calico)
- kubectl apply -f calico.yaml
然后执行命令安装calico网络插件

如果出现上述提示,说明我们的yaml文件有可能换行符搞错了等等。

再重新下载就好了。

我们如何查看集群部署了哪些应用呢?
- # 查看集群部署了哪些应用
- docker ps
- # 等价于
- kubectl get pods -A
- # 运行中的应用在docker里面叫容器,在k8s里面叫Pod,至于为什么,后续再讲


以上,master节点就准备就绪了!
前面初始化主节点成功后的提示中有步骤:
- kubeadm join cluster-endpoint:6443 --token 3e54se.alzs9d1mkf30f25w \
- --discovery-token-ca-cert-hash sha256:689c076e294bdbb588103a51aaa7248b8a0df34bde634a6189d311ad46a02856
我们只需要将它在另外两台服务器各自执行即可。
如果加入报错,请查看是否已经关闭了防火墙,确保关闭防火墙然后执行:
sysctl -w net.ipv4.ip_forward=1

ok,然后去master查看一下节点信息。


我们也可以通过linux的命令 watch -n 1 kubectl get pods -A,每一秒查看一下状态


OK了,我们再看看

至此,K8S集群就跑起来了。
token超过24小时就失效了,如果我们还没有加入从节点,或者想加入新的从节点,可以在master节点执行如下命令,让它重新生成
kubeadm token create --print-join-command
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.3.1/aio/deploy/recommended.yaml

如果网络不好安装不了就复制下面的,将它写入到一个yaml文件中,然后执行该文件即可:
- # 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.
-
- apiVersion: v1
- kind: Namespace
- metadata:
- name: kubernetes-dashboard
-
- ---
-
- apiVersion: v1
- kind: ServiceAccount
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
-
- ---
-
- kind: Service
- apiVersion: v1
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
- spec:
- ports:
- - port: 443
- targetPort: 8443
- selector:
- k8s-app: kubernetes-dashboard
-
- ---
-
- apiVersion: v1
- kind: Secret
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard-certs
- namespace: kubernetes-dashboard
- type: Opaque
-
- ---
-
- apiVersion: v1
- kind: Secret
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard-csrf
- namespace: kubernetes-dashboard
- type: Opaque
- data:
- csrf: ""
-
- ---
-
- apiVersion: v1
- kind: Secret
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard-key-holder
- namespace: kubernetes-dashboard
- type: Opaque
-
- ---
-
- kind: ConfigMap
- apiVersion: v1
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard-settings
- namespace: kubernetes-dashboard
-
- ---
-
- kind: Role
- apiVersion: rbac.authorization.k8s.io/v1
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
- rules:
- # Allow Dashboard to get, update and delete Dashboard exclusive secrets.
- - apiGroups: [""]
- resources: ["secrets"]
- resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs", "kubernetes-dashboard-csrf"]
- 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.
- - apiGroups: [""]
- resources: ["services"]
- resourceNames: ["heapster", "dashboard-metrics-scraper"]
- verbs: ["proxy"]
- - apiGroups: [""]
- resources: ["services/proxy"]
- resourceNames: ["heapster", "http:heapster:", "https:heapster:", "dashboard-metrics-scraper", "http:dashboard-metrics-scraper"]
- verbs: ["get"]
-
- ---
-
- kind: ClusterRole
- apiVersion: rbac.authorization.k8s.io/v1
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard
- rules:
- # Allow Metrics Scraper to get metrics from the Metrics server
- - apiGroups: ["metrics.k8s.io"]
- resources: ["pods", "nodes"]
- verbs: ["get", "list", "watch"]
-
- ---
-
- apiVersion: rbac.authorization.k8s.io/v1
- kind: RoleBinding
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
- roleRef:
- apiGroup: rbac.authorization.k8s.io
- kind: Role
- name: kubernetes-dashboard
- subjects:
- - kind: ServiceAccount
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
-
- ---
-
- apiVersion: rbac.authorization.k8s.io/v1
- kind: ClusterRoleBinding
- metadata:
- name: kubernetes-dashboard
- roleRef:
- apiGroup: rbac.authorization.k8s.io
- kind: ClusterRole
- name: kubernetes-dashboard
- subjects:
- - kind: ServiceAccount
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
-
- ---
-
- kind: Deployment
- apiVersion: apps/v1
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- name: kubernetes-dashboard
- namespace: kubernetes-dashboard
- spec:
- replicas: 1
- revisionHistoryLimit: 10
- selector:
- matchLabels:
- k8s-app: kubernetes-dashboard
- template:
- metadata:
- labels:
- k8s-app: kubernetes-dashboard
- spec:
- containers:
- - name: kubernetes-dashboard
- image: kubernetesui/dashboard:v2.3.1
- imagePullPolicy: Always
- ports:
- - containerPort: 8443
- protocol: TCP
- args:
- - --auto-generate-certificates
- - --namespace=kubernetes-dashboard
- # 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
- securityContext:
- allowPrivilegeEscalation: false
- readOnlyRootFilesystem: true
- runAsUser: 1001
- runAsGroup: 2001
- volumes:
- - name: kubernetes-dashboard-certs
- secret:
- secretName: kubernetes-dashboard-certs
- - name: tmp-volume
- emptyDir: {}
- serviceAccountName: kubernetes-dashboard
- nodeSelector:
- "kubernetes.io/os": linux
- # Comment the following tolerations if Dashboard must not be deployed on master
- tolerations:
- - key: node-role.kubernetes.io/master
- effect: NoSchedule
-
- ---
-
- kind: Service
- apiVersion: v1
- metadata:
- labels:
- k8s-app: dashboard-metrics-scraper
- name: dashboard-metrics-scraper
- namespace: kubernetes-dashboard
- spec:
- ports:
- - port: 8000
- targetPort: 8000
- selector:
- k8s-app: dashboard-metrics-scraper
-
- ---
-
- kind: Deployment
- apiVersion: apps/v1
- metadata:
- labels:
- k8s-app: dashboard-metrics-scraper
- name: dashboard-metrics-scraper
- namespace: kubernetes-dashboard
- spec:
- replicas: 1
- revisionHistoryLimit: 10
- selector:
- matchLabels:
- k8s-app: dashboard-metrics-scraper
- template:
- metadata:
- labels:
- k8s-app: dashboard-metrics-scraper
- annotations:
- seccomp.security.alpha.kubernetes.io/pod: 'runtime/default'
- spec:
- containers:
- - name: dashboard-metrics-scraper
- image: kubernetesui/metrics-scraper:v1.0.6
- ports:
- - containerPort: 8000
- protocol: TCP
- livenessProbe:
- httpGet:
- scheme: HTTP
- path: /
- port: 8000
- initialDelaySeconds: 30
- timeoutSeconds: 30
- volumeMounts:
- - mountPath: /tmp
- name: tmp-volume
- securityContext:
- allowPrivilegeEscalation: false
- readOnlyRootFilesystem: true
- runAsUser: 1001
- runAsGroup: 2001
- serviceAccountName: kubernetes-dashboard
- nodeSelector:
- "kubernetes.io/os": linux
- # Comment the following tolerations if Dashboard must not be deployed on master
- tolerations:
- - key: node-role.kubernetes.io/master
- effect: NoSchedule
- volumes:
- - name: tmp-volume
- emptyDir: {}
kubectl edit svc kubernetes-dashboard -n kubernetes-dashboard
type: ClusterIP 改为 type: NodePort
相当于docker中将内部的端口映射到linux的某个端口

找到放行的端口
- kubectl get svc -A |grep kubernetes-dashboard
- ## 如果是云服务器,找到端口,在安全组放行

访问: https://集群任意IP:端口 https://192.168.37.110:31820/

发现虚拟机部署的无法访问,云服务器则没有问题。
我后面试了试Google、Edge都不行,华为浏览器、火狐浏览器可以访问到:

具体怎么解决,这个我放到后面有时间再处理吧~
创建一个配置文件dash-usr.yaml
- #创建访问账号,准备一个yaml文件; vi dash.yaml
- apiVersion: v1
- kind: ServiceAccount
- metadata:
- name: admin-user
- namespace: kubernetes-dashboard
- ---
- apiVersion: rbac.authorization.k8s.io/v1
- kind: ClusterRoleBinding
- metadata:
- name: admin-user
- roleRef:
- apiGroup: rbac.authorization.k8s.io
- kind: ClusterRole
- name: cluster-admin
- subjects:
- - kind: ServiceAccount
- name: admin-user
- namespace: kubernetes-dashboard


这个可视化界面是通过令牌登录的,我们可以通过如下命令生成访问令牌:
- #获取访问令牌
- kubectl -n kubernetes-dashboard get secret $(kubectl -n kubernetes-dashboard get sa/admin-user -o jsonpath="{.secrets[0].name}") -o go-template="{{.data.token | base64decode}}"



值得注意的是,我们的这些kubectl命令都需要在master节点上运行,别整岔劈了!
另外,我们重启后,k8s集群正常来说就会自动启动,只不过部分应用需要时间慢慢启动,等他们全部running
如果发现没有重启成功,那么检查一下swap交换分区是不是没有关闭?防火墙是不是打开了?docker是不是都启动了?
遇事不要慌,逐一进行排查,这也是处理问题的能力。我在搭建的过程中,也遇到了不少的坑,正常。不过只要严格按照上述过程执行,我相信问题不大的。
好了,我们下一个阶段见!