kubernetes安装与节点初始化

一、在master节点与node节点均要操作如下：

1.安装并启动docker

#卸载旧版本
sudo yum remove -y docker \
docker-client \
docker-client-latest \
docker-common \
docker-latest \
docker-latest-logrotate \
docker-logrotate \
docker-selinux \
docker-engine-selinux \
docker-engine

#设置 yum repository
sudo yum install -y yum-utils \
device-mapper-persistent-data \
lvm2
sudo yum-config-manager \
--add-repo \
https://download.docker.com/linux/centos/docker-ce.repo

#安装并启动
sudo yum install -y docker-ce-18.09.7 docker-ce-cli-18.09.7 containerd.io
sudo systemctl enable docker
sudo systemctl start docker

2.安装 nfs-utils (只有安装才能挂载nfs网络存储)

sudo yum install -y nfs-utils

3.k8s基本配置

#配置k8s的yum源
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
EOF

#关闭防火墙、SeLinux、swap
systemctl stop firewalld
systemctl disable firewalld

setenforce 0
sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config

swapoff -a
yes | cp /etc/fstab /etc/fstab_bak
cat /etc/fstab_bak |grep -v swap > /etc/fstab

#修改etc/sysctl.conf、添加如下
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1

#执行命令以应用
sysctl -p

#安装kubelet、kubeadm、kubectl
yum install -y kubelet-1.15.1 kubeadm-1.15.1 kubectl-1.15.1

安装成功如图：

#设置docker镜像，使用国内镜像

curl -sSL https://get.daocloud.io/daotools/set_mirror.sh | sh -s http://f1361db2.m.daocloud.io

#重启 docker，并启动 kubelet

systemctl daemon-reload
systemctl restart docker
systemctl enable kubelet && systemctl start kubelet

二、初始化master节点（均在master节点执行）

1.配置 apiserver.demo 的域名，其中的 x.x.x.x 为 demo-master主机的实际 ip 地址

echo "x.x.x.x  apiserver.demo" >> /etc/hosts

2.创建 ./kubeadm-config.yaml，，podSubnet 所使用的网段不能与节点所在的网段重叠

cat <<EOF > ./kubeadm-config.yaml
apiVersion: kubeadm.k8s.io/v1beta1
kind: ClusterConfiguration
kubernetesVersion: v1.15.1
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
controlPlaneEndpoint: "apiserver.demo:6443"
networking:
  podSubnet: "10.100.0.1/20"
EOF

3.初始化 apiserver

kubeadm init --config=kubeadm-config.yaml --upload-certs

echo 1 > /proc/sys/net/bridge/bridge-nf-call-iptables
echo 1 > /proc/sys/net/bridge/bridge-nf-call-ip6tables

4.初始化 root 用户的 kubectl 配置

rm -rf /root/.kube/
mkdir /root/.kube/
cp -i /etc/kubernetes/admin.conf /root/.kube/config

5.安装 calico

kubectl apply -f https://docs.projectcalico.org/v3.6/getting-started/kubernetes/installation/hosted/kubernetes-datastore/calico-networking/1.7/calico.yaml

6.查看是否所有的容器组处于 Running 状态

watch kubectl get pod -n kube-system

7.检查 master 初始化结果

kubectl get nodes

三、初始化worker节点

获得join命令参数（在master节点执行）

1.在 master 节点 demo-master 节点执行

kubeadm token create --print-join-command

2.获取kubeadm join 命令及参数

kubeadm join apiserver.demo:6443 --token mpfjma.4vjjg8flqihor4vt --discovery-token-ca-cert-hash sha256:6f7a8e40a810323672de5eee6f4d19aa2dbdb38411845a1bf5dd63485c43d303

初始化worker（在worker节点执行）

x.x.x.x 替换为 demo-master 的实际 ip

echo “x.x.x.x apiserver.demo” >> /etc/hosts
kubeadm join apiserver.demo:6443 --token mpfjma.4vjjg8flqihor4vt --discovery-token-ca-cert-hash sha256:6f7a8e40a810323672de5eee6f4d19aa2dbdb38411845a1bf5dd63485c43d303

检查初始化结果

在master节点上执行，显示各节点即可

kubectl get nodes