通过kubeadm部署Kubernetes集群
一、概述
Kubeadm 是一个工具，它提供了 kubeadm init 以及 kubeadm join 这两个命令作为快速创建 kubernetes 集群的最佳实践。
kubeadm 通过执行必要的操作来启动和运行一个最小可用的集群。它被故意设计为只关心启动集群，而不是准备节点环境的工作。同样的，诸如安装各种各样的可有可无的插件，例如 Kubernetes 控制面板、监控解决方案以及特定云提供商的插件，这些都不在它负责的范围。
二、 就绪检测
2.1 机器就位
| Hostname | IP | 说明 |
|---|---|---|
| peng-master-1 | 172.16.196.200 | 至少2CPU |
| peng-node-1 | 172.16.196.201 | |
| peng-node-2 | 172.16.196.202 |
注：所以节点操作以下设置。
2.2 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
2.3 关闭selinux
sed -i 's/enforcing/disabled/' /etc/selinux/config
setenforce 0
2.4 关闭swap
swapoff -a # 临时关闭
sed -ri 's/.*swap.*/#&/' /etc/fstab #永久关闭
2.5 将桥接的ipv4流量传到iptables的链
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system
2.6 时间同步
yum install ntpdate -y
ntpdate time.windows.com
三、安装Docker
注：所有节点安装
3.1 安装Docker源
yum install -y wget && wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
3.2 安装Docker
1. 安装指定版本Docker
yum list | grep docker-ce
containerd.io.x86_64 1.3.7-3.1.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.13-3.el7 docker-ce-stable
docker-ce-cli.x86_64 1:19.03.13-3.el7 docker-ce-stable
docker-ce-selinux.noarch 17.03.3.ce-1.el7 docker-ce-stable
yum install -y docker-ce-19.03.13-3.el7.x86_64
2. 开机启动与启动Docker服务
systemctl enable docker && systemctl start docker
3. 查看Docker，确保已启动
docker version
docker ps
四、安装kubeadm
注：所有节点安装
4.1 添加阿里云yum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
4.2 安装kubeadm、kubelet、kubectl
# yum list | grep kubelet
kubelet.x86_64 1.19.2-0 kubernetes
[root@peng-master-1 ~]# yum list | grep kubeadm
kubeadm.x86_64 1.19.2-0 kubernetes
[root@peng-master-1 ~]# yum list | grep kubectl
kubectl.x86_64 1.19.2-0 kubernetes
yum install -y kubelet-1.19.2-0 kubeadm-1.19.2-0 kubectl-1.19.2-0
设置开机启动
systemctl enable kubelet
五、配置 Master
注：只在master节点执行
kubeadm init \
--apiserver-advertise-address=172.16.196.200 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version v1.19.2 \
--service-cidr=10.1.0.0/16 \
--pod-network-cidr=10.244.0.0/16
安装成功后提示：
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
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/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 172.16.196.200:6443 --token eflt49.q765j3u6zj7yaq0r \
--discovery-token-ca-cert-hash sha256:18170da9910aa1a9891ca02053a90b9401650534cc485e5320eb8716ab738f29
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
六、安装Flannel
github地址：https://github.com/coreos/flannel
6.1 下载镜像
注：镜像每个节点安装
[root@peng-master-1 ~]# wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
[root@peng-master-1 ~]# grep image kube-flannel.yml
image: quay.io/coreos/flannel:v0.13.0-rc2
image: quay.io/coreos/flannel:v0.13.0-rc2
[root@peng-master-1 ~]# docker pull quay.io/coreos/flannel:v0.13.0-rc2
没有翻墙本地似乎可以拉取成功，如果其有些节点太慢可以打包同步。
[root@peng-master-1 ~]# docker save -o flannel.tar quay.io/coreos/flannel:v0.13.0-rc2
[root@peng-master-1 ~]# scp flannel.tar root@172.16.196.201:~/
[root@peng-node-1 ~]# docker load -i flannel.tar
6.2 安装Flannel
注：只Master节点操作
kubectl apply -f kube-flannel.yml
七、添加节点
注：Node节点操作
7.1 添加Node
kubeadm join 172.16.196.200:6443 --token eflt49.q765j3u6zj7yaq0r \
--discovery-token-ca-cert-hash sha256:18170da9910aa1a9891ca02053a90b9401650534cc485e5320eb8716ab738f29
7.2 查看Node
[root@peng-master-1 ~]# kubectl get node
NAME STATUS ROLES AGE VERSION
peng-master-1 Ready master 54m v1.19.2
peng-node-1 Ready <none> 13m v1.19.2
peng-node-2 Ready <none> 11m v1.19.2
八、创建示例
用我们前面的用过的示例进行测试
apiVersion: v1
kind: Service
metadata:
name: go-svc
spec:
type: NodePort
ports:
- port: 36001
targetPort: 38001
selector:
name: k8s-go-demo
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: k8s-go-demo
spec:
replicas: 3
selector:
matchLabels:
name: k8s-go-demo
template:
metadata:
labels:
name: k8s-go-demo
spec:
containers:
- name: k8s-go-demo
image: pengbotao/k8s-go-demo:v1
imagePullPolicy: IfNotPresent
ports:
- containerPort: 38001
创建
# kubectl apply -f k8s-go-demo.yaml
service/go-svc created
deployment.apps/k8s-go-demo created
查看
[root@peng-master-1 k8s]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
go-svc NodePort 10.1.35.223 <none> 36001:31169/TCP 9m43s
[root@peng-master-1 k8s]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
k8s-go-demo-6bd6875cc-jw9gg 1/1 Running 0 8m21s 10.244.1.2 peng-node-1 <none> <none>
k8s-go-demo-6bd6875cc-ktscm 1/1 Running 0 8m21s 10.244.1.3 peng-node-1 <none> <none>
k8s-go-demo-6bd6875cc-w2cgv 1/1 Running 0 8m21s 10.244.2.2 peng-node-2 <none> <none>
访问
# 虚拟机访问
[root@peng-master-1 ~]# curl 10.1.35.223:36001
{"ClientIP":"10.244.0.0","Host":"k8s-go-demo-6bd6875cc-jw9gg","ServerIP":"10.244.1.2","Time":"2020-09-25 01:42:59","Version":"v1"}
# 宿主机访问
pengbotao:~ peng$ curl http://172.16.196.200:31169
{"ClientIP":"10.244.0.0","Host":"k8s-go-demo-6bd6875cc-w2cgv","ServerIP":"10.244.2.2","Time":"2020-09-25 01:43:37","Version":"v1"}
pengbotao:~ peng$ curl http://172.16.196.201:31169
{"ClientIP":"10.244.1.1","Host":"k8s-go-demo-6bd6875cc-ktscm","ServerIP":"10.244.1.3","Time":"2020-09-25 01:43:42","Version":"v1"}
九、安装Dashboard
github地址：https://github.com/kubernetes/dashboard
9.1 安装
Dashboard没有使用nodeport，下载yaml文件，并对Service部分增加了type和nodePort节点。
wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.4/aio/deploy/recommended.yaml
---
kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kubernetes-dashboard
spec:
type: NodePort
ports:
- port: 443
targetPort: 8443
nodePort: 32000
selector:
k8s-app: kubernetes-dashboard
---
镜像也是一样的安装方式，拉好某一台后同步到其他机器：
[root@peng-master-1 ~]# grep image recommended.yaml
image: kubernetesui/dashboard:v2.0.4
imagePullPolicy: Always
image: kubernetesui/metrics-scraper:v1.0.4
9.2 配置token
cat > dashboard-adminuser.yaml << EOF
apiVersion: v1
kind: ServiceAccount
metadata:
name: aks-dashboard-admin
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: aks-dashboard-admin
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: aks-dashboard-admin
namespace: kube-system
EOF
kubectl apply -f dashboard-adminuser.yaml
查看Token
kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep aks-dashboard-admin | awk '{print $1}')
期间出现的问题时获取到的Token看不到名称空间，应该是权限的问题，按上面产生的Token可以。
9.3 宿主机访问
https://peng-master-1:32000/
用前一步的Token登录即可，Chrome可能无法登录，可以用Firefox试试。
说明：以上操作参考[南宫乘风]的教程，表示感谢。除Dashboard部分配置Token有调整外，其他基本一致。
-- EOF --
最后更新于：
2024-08-17 14:44
发表于：
2020-11-30 22:00
标签：
Kubernetes
容器化
