环境准备
这里使用Parallels Desktop 新建三个虚拟机，网络配置使用共享网络，确保三个主机有三个不同的网卡MAC地址，确保三个虚拟机之间可以互相ping通。三个虚拟机配置如下
| 主机名 | IP |
|---|---|
| master1 | 192.168.1.27 |
| node1 | 192.168.1.28 |
| node2 | 192.168.1.29 |
配置root密码，修改主机名
su passwd root
vim /etc/hostname
配置master的本地DNS
[root@master1 ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.27 hongyi.master1.com master1
192.168.1.28 hongyi.node1.com node1
192.168.1.29 hongyi.node2.com node2
永久关闭swap
free -h
swapoff -a
// 修改/etc/fstab配置文件，注释掉swap的挂载
配置SELinux和firewalld
[root@master1 ~] sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config # 修改配置永久生效，需重启
[root@master1 ~]# setenforce 0
#关闭防火墙
[root@master1 ~]# systemctl stop firewalld
[root@master1 ~]# systemctl disable firewalld
Removed symlink /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
Removed symlink /etc/systemd/system/basic.target.wants/firewalld.service.
yum仓库配置
由于需要下载相关镜像，这里使用阿里云的镜像仓库
配置docker-ce的镜像仓库
[root@master1 yum.repos.d]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
[root@master1 yum.repos.d]# touch kubenetes.repo
[root@master1 yum.repos.d]# vim kubenetes.repo
[root@master1 yum.repos.d]# cat kubenetes.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
将两个仓库配置拷贝到node节点
scp ./docker-ce.repo node2:/etc/yum.repos.d/docker-ce.repo
scp ./kubenetes.repo node1:/etc/yum.repos.d/kubenetes.repo
Master节点配置
master需要安装的组件包括
- docker-ce
- kubeadm
- kubectl
- kubelet
安装组件，并启动docker
yum install kubeadm-1.15.2 kubectl-1.15.2 kubelet-1.15.2 docker-ce -y
systemctl start docker
systemctl enable docker
docker info
由于墙的原因，这里我们先使用脚本准备需要的镜像，pull下来之后重新tag
[parallels@master1 ~]$ cat /dockerpull.sh
#!/bin/bash
echo "Hello World !"
#根据上面报错的提示选择相应的版本
docker pull mirrorgooglecontainers/kube-apiserver:v1.15.2
docker pull mirrorgooglecontainers/kube-controller-manager:v1.15.2-beta.0
docker pull mirrorgooglecontainers/kube-scheduler:v1.15.2-beta.0
docker pull mirrorgooglecontainers/kube-proxy:v1.15.2
docker pull mirrorgooglecontainers/pause:3.1
docker pull mirrorgooglecontainers/etcd:3.3.10
docker pull coredns/coredns:1.3.1
#改tag
docker tag mirrorgooglecontainers/kube-apiserver:v1.15.2 k8s.gcr.io/kube-apiserver:v1.15.2
docker tag mirrorgooglecontainers/kube-controller-manager:v1.15.2-beta.0 k8s.gcr.io/kube-controller-manager:v1.15.2
docker tag mirrorgooglecontainers/kube-scheduler:v1.15.2-beta.0 k8s.gcr.io/kube-scheduler:v1.15.2
docker tag mirrorgooglecontainers/kube-proxy:v1.15.2 k8s.gcr.io/kube-proxy:v1.15.2
docker tag mirrorgooglecontainers/pause:3.1 k8s.gcr.io/pause:3.1
docker tag mirrorgooglecontainers/etcd:3.3.10 k8s.gcr.io/etcd:3.3.10
docker tag coredns/coredns:1.3.1 k8s.gcr.io/coredns:1.3.1
#清理镜像
docker rmi mirrorgooglecontainers/kube-apiserver:v1.15.2
docker rmi mirrorgooglecontainers/kube-controller-manager:v1.15.2-beta.0
docker rmi mirrorgooglecontainers/kube-scheduler:v1.15.2-beta.0
docker rmi mirrorgooglecontainers/kube-proxy:v1.15.2
docker rmi mirrorgooglecontainers/pause:3.1
docker rmi mirrorgooglecontainers/etcd:3.3.10
docker rmi coredns/coredns:1.3.1
查看一下镜像
[root@master1 yum.repos.d]# docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
k8s.gcr.io/kube-proxy v1.15.2 167bbf6c9338 4 months ago 82.4MB
k8s.gcr.io/kube-apiserver v1.15.2 34a53be6c9a7 4 months ago 207MB
k8s.gcr.io/kube-controller-manager v1.15.2 575346c7506b 5 months ago 159MB
k8s.gcr.io/kube-scheduler v1.15.2 38d61dd6e105 5 months ago 81.1MB
k8s.gcr.io/coredns 1.3.1 eb516548c180 11 months ago 40.3MB
k8s.gcr.io/etcd 3.3.10 2c4adeb21b4f 12 months ago 258MB
k8s.gcr.io/pause 3.1 da86e6ba6ca1 24 months ago 742kB
使用kubeadm init 初始化集群的control-plane
kubeadm init --kubernetes-version=v1.15.2 --pod-network-cidr=10.224.0.0/16 --service-cidr=10.96.0.0/12 --ignore-preflight-errors=Swap
在经过初始化一系列的phase之后，提示接下来的操作
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 192.168.1.27:6443 --token 8bzhtc.c97lhb44g0y7l4uy \
--discovery-token-ca-cert-hash sha256:8dd9c308281a85175b2ef9106110c2a81e2b2374e230717d0882b04f31b9bc69
执行提示的指令
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
// 由于本来就是用root用户操作的，第三句可以省去
接着命令提示我们去设置网络，先查看下节点的状态，这里的NotReady表明网络不可用
[root@master1 yum.repos.d]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master1 NotReady master 6m20s v1.15.2
这里使用flannel作为网络的支持组件，手动部署flannel
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
如果在虚拟机里下载不下来这个yml文件，可以先在宿主机下好之后拷贝到虚拟机中。
[root@master1 yum.repos.d]# kubectl apply -f /kube-flannel.yml
podsecuritypolicy.policy/psp.flannel.unprivileged created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds-amd64 created
daemonset.apps/kube-flannel-ds-arm64 created
daemonset.apps/kube-flannel-ds-arm created
daemonset.apps/kube-flannel-ds-ppc64le created
daemonset.apps/kube-flannel-ds-s390x created
稍等片刻，master节点的状态就会变为Ready
[root@master1 yum.repos.d]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master1 Ready master 12m v1.15.2
加入Node节点
Node节点需要手动安装的组件包括
- kubeadm
- kubelet
- docker-ce
[root@node1 ~]# yum install docker-ce kubelet-1.15.2 kubeadm-1.15.2 -y
[root@node1 ~]# systemctl start docker
[root@node1 ~]# systemctl enable docker
[root@node1 ~]# systemctl start kubelet
[root@node1 ~]# systemctl enable kubelet
在join集群之前，由于墙的原因，node节点也需要准备好相关镜像，node节点使用这个dockerpull.sh脚本拉取镜像
[root@centos-7-k8s-node1 ~]# cat /dockerpull.sh
#!/bin/bash
docker pull mirrorgooglecontainers/kube-proxy:v1.15.2
docker pull mirrorgooglecontainers/pause:3.1
#改tag
docker tag mirrorgooglecontainers/kube-proxy:v1.15.2 k8s.gcr.io/kube-proxy:v1.15.2
docker tag mirrorgooglecontainers/pause:3.1 k8s.gcr.io/pause:3.1
#清理镜像
docker rmi mirrorgooglecontainers/kube-proxy:v1.15.2
docker rmi mirrorgooglecontainers/pause:3.1
镜像准备好之后，使用kubeadm join加入集群（master执行kuebadm init时提示的指令）
kubeadm join 192.168.1.27:6443 --token 8bzhtc.c97lhb44g0y7l4uy \
--discovery-token-ca-cert-hash sha256:8dd9c308281a85175b2ef9106110c2a81e2b2374e230717d0882b04f31b9bc69
稍等片刻，等Node节点加入集群成功后，在master节点查看所有节点状态
NAME STATUS ROLES AGE VERSION
master1 Ready master 40m v1.15.2
node1 Ready <none> 13m v1.15.2
node2 Ready <none> 47s v1.15.2
[root@master1 yum.repos.d]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-5c98db65d4-fstfc 1/1 Running 0 43m
coredns-5c98db65d4-wmqln 1/1 Running 0 43m
etcd-master1 1/1 Running 0 42m
kube-apiserver-master1 1/1 Running 0 42m
kube-controller-manager-master1 1/1 Running 0 42m
kube-flannel-ds-amd64-rhw8v 1/1 Running 0 31m
kube-flannel-ds-amd64-wrts8 1/1 Running 0 3m41s
kube-flannel-ds-amd64-zmvdv 1/1 Running 0 15m
kube-proxy-9d2jq 1/1 Running 0 15m
kube-proxy-l2kd8 1/1 Running 0 3m41s
kube-proxy-sh8wp 1/1 Running 0 43m
kube-scheduler-master1 1/1 Running 0 42m
至此，一个未安装任何应用的一个集群就部署完毕了。
have fun
