参考：https://blog.51cto.com/lizhenliang/2530583
服务器准备
| 角色 | ip |
|---|---|
| k8s-master | 192.168.2.36 |
| k8s-node1 | 192.168.2.37 |
| k8s-node2 | 192.168.2.38 |
环境准备
关闭防火墙：
systemctl stop firewalld
systemctl disable firewalld
关闭selinux：
sed -i 's/enforcing/disabled/'/etc/selinux/config # 永久
setenforce 0 # 临时
关闭swap：
swapoff -a # 临时
vim /etc/fstab # 永久
根据规划设置主机名：
hostnamectl set-hostname
在master添加hosts：
cat >>/etc/hosts << EOF
192.168.2.36 k8s-master
192.168.2.37 k8s-node1
192.168.2.38 k8s-node2
EOF
将桥接的IPv4流量传递到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
[root@k8s-master ~]# sysctl --system # 生效
时间同步：
yum install ntpdate -y
ntpdate time.windows.com
所有节点安装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
systemctl enable docker && systemctl start docker
所有节点安装kubeadm，kubelet和kubectl
添加阿里云YUM软件源
cat < /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
EOF
安装kubeadm，kubelet和kubectl
- kubeadm：引导集群的命令；
- kubelet：运行在集群中所有机器上并执行诸如启动pod和容器之类操作的组件;
- kubectl：操作集群的命令行单元；
yum install -y kubelet kubeadm kubectl
systemctl enable kubelet
部署Kubernetes Master
[root@k8s-master ~]# kubeadm init --apiserver-advertise-address=192.168.2.36 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.19.3 --service-cidr=10.1.0.0/16 --pod-network-cidr=10.244.0.0/16
W1022 17:37:15.075220 1979 configset.go:348] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.19.3
[preflight] Running pre-flight checks
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s-master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.1.0.1 192.168.2.36]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.2.36 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.2.36 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 15.501800 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.19" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node k8s-master as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: 8mgl0u.lrcvv7sf6o0d8v2i
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
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 192.168.2.36:6443 --token 8mgl0u.lrcvv7sf6o0d8v2i \
--discovery-token-ca-cert-hash sha256:f91c9e0ce42468d1ce18a014a825e81cd8d52d231514463b553a3aaac9931e23
—apiserver-advertise-address 集群通告地址
—image-repository 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。
—kubernetes-version K8s版本，与上面安装的一致
—service-cidr 集群内部虚拟网络，Pod统一访问入口
—pod-network-cidr Pod网络，与下面部署的CNI网络组件yaml中保持一致
拷贝kubectl使用的连接k8s认证文件到默认路径：
[root@k8s-master ~]# mkdir -p $HOME/.kube
[root@k8s-master ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@k8s-master ~]# chown $(id -u):$(id -g) $HOME/.kube/config
安装网络插件
[root@k8s-master ~]# wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
[root@k8s-master ~]# kubectl apply -f kube-flannel.yml
[root@k8s-master ~]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-6d56c8448f-9qclf 1/1 Running 0 6m16s
coredns-6d56c8448f-gntqj 1/1 Running 0 6m16s
etcd-k8s-master 1/1 Running 0 6m32s
kube-apiserver-k8s-master 1/1 Running 0 6m32s
kube-controller-manager-k8s-master 1/1 Running 0 6m32s
kube-flannel-ds-h4vtg 1/1 Running 0 60s
kube-proxy-rz4sp 1/1 Running 0 6m16s
kube-scheduler-k8s-master 1/1 Running 0 6m32s
加入Kubernetes Node
[root@k8s-node1 ~]# kubeadm join 192.168.2.36:6443 --token 8mgl0u.lrcvv7sf6o0d8v2i \
> --discovery-token-ca-cert-hash sha256:f91c9e0ce42468d1ce18a014a825e81cd8d52d231514463b553a3aaac9931e23
[root@k8s-node2 ~]# kubeadm join 192.168.2.36:6443 --token 8mgl0u.lrcvv7sf6o0d8v2i \
> --discovery-token-ca-cert-hash sha256:f91c9e0ce42468d1ce18a014a825e81cd8d52d231514463b553a3aaac9931e23
[root@k8s-master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master Ready master 16m v1.19.3
k8s-node1 Ready 6m56s v1.19.3
k8s-node2 Ready 6m53s v1.19.3