k8s - 从蒙圈到集群搭建（Centos7）

安装docker

删除已安装的docker

sudo yum remove docker \
                  docker-client \
                  docker-client-latest \
                  docker-common \
                  docker-latest \
                  docker-latest-logrotate \
                  docker-logrotate \
                  docker-selinux \
                  docker-engine-selinux \
                  docker-engine
                  

11.png

配置阿里云docker 源

# Set up repository
sudo yum install -y yum-utils device-mapper-persistent-data lvm2

# Use Aliyun Docker
sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

安装docker

• 安装docker
  yum install docker-ce

• 检查安装

  
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• 启动docker
  systemctl start docker

• 设置开机启动
  systemctl enable docker

安装 kubeadm, kubelet and kubectl

• 设置阿里云镜像

cat <<EOF > /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

• Set SELinux in permissive mode (effectively disabling it)
  setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config

• 安装
  yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes

• 检查版本

  
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• 设置开机启动
  systemctl enable --now kubelet

cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system

• 关闭防火墙
  systemctl disable firewalld
• 关闭内存交换
  swapoff -a
  注释/etc/fstab 最后一行

使用kubeadm启动集群

• 修改主机名称 /etc/hostname

• 初始化集群 kubeadm init ， 被墙了，拉取不了所需要的镜像

• 查看所需要的镜像 kubeadm config images list
  

  image.png

• 绕道阿里云下载(保存为shell执行) 参考 https://my.oschina.net/u/2306127/blog/1843053

echo ""
echo "=========================================================="
echo "Pull Kubernetes v1.14.2 Images from aliyuncs.com ......"
echo "=========================================================="
echo ""
MY_REGISTRY=registry.cn-hangzhou.aliyuncs.com/openthings
## 拉取镜像
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.14.2
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.14.2
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.14.2
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.14.2
docker pull ${MY_REGISTRY}/k8s-gcr-io-etcd:3.3.10
docker pull ${MY_REGISTRY}/k8s-gcr-io-pause:3.1
docker pull ${MY_REGISTRY}/k8s-gcr-io-coredns:1.3.1
## 添加Tag
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.14.2 k8s.gcr.io/kube-apiserver:v1.14.2
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.14.2 k8s.gcr.io/kube-scheduler:v1.14.2
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.14.2 k8s.gcr.io/kube-controller-manager:v1.14.2
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.14.2 k8s.gcr.io/kube-proxy:v1.14.2
docker tag ${MY_REGISTRY}/k8s-gcr-io-etcd:3.3.10 k8s.gcr.io/etcd:3.3.10
docker tag ${MY_REGISTRY}/k8s-gcr-io-pause:3.1 k8s.gcr.io/pause:3.1
docker tag ${MY_REGISTRY}/k8s-gcr-io-coredns:1.3.1 k8s.gcr.io/coredns:1.3.1
## 移除镜像
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.14.2
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.14.2
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.14.2
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.14.2
docker rmi ${MY_REGISTRY}/k8s-gcr-io-etcd:3.3.10
docker rmi ${MY_REGISTRY}/k8s-gcr-io-pause:3.1
docker rmi ${MY_REGISTRY}/k8s-gcr-io-coredns:1.3.1
echo ""
echo "=========================================================="
echo "Pull Kubernetes v1.14.2 Images FINISHED."
echo "into registry.cn-hangzhou.aliyuncs.com/openthings, "
echo " by openthings@https://my.oschina.net/u/2306127."
echo "=========================================================="
echo ""

• 查看集群所需要的镜像 docker iamges

image.png

• 再次初始化 kubeadm init
  

  image.png

• 初始化成功，注意箭头所在命令，依次执行，否则无法连接kube-apiserver

  
  image.png

• 当前节点状态为 NotReady，查看系统日志 journalctl -xeu kubelet
  

  image.png

• 安装pod网络插件
  kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/62e44c867a2846fefb68bd5f178daf4da3095ccb/Documentation/kube-flannel.yml

• 重启kubelet systemctl restart kubelet

• 查看节点状态 kubectl get nodes
  

  image.png