安装Kubernetes

网上kubernetes各种安装教程不少，但要么是上古时期的版本，要么三言两语匆匆带过。尤其是在我们还需要用到显卡的情况下…………

这里总结一下自己安装kubernetes的全部过程。

如果你还没有安装Docker，请先参考这篇文章安装Docker。

# 添加kubernetes仓库
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
    deb https://apt.kubernetes.io/ kubernetes-xenial main
    EOF


# 更新仓库
apt-get update
apt-get install kubelet kubeadm kubectl

拉取依赖镜像

本步骤仅适用于位于GFW影响范围内的主机

运行以下脚本（如果您预期安装的kubernetes版本不是v1.13.2，请运行kubeadm config images list并依据返回结果运行脚本）：

#!/bin/bash
set -e    
if [ -n "$1" ]; then
    K8S_VERSION=$1
else
    K8S_VERSION=v1.13.2
fi
if [ -n "$2" ]; then
    DASHBOARD_VERSION=$2
else
    DASHBOARD_VERSION=v1.10.1
fi
if [ -n "$3" ]; then
    ETCD_VERSION=$3
else
    ETCD_VERSION=3.2.24
fi
if [ -n "$4" ]; then
    PAUSE_VERSION=$4
else
    PAUSE_VERSION=3.1
fi
if [ -n "$5" ]; then
    DNS_VERSION=$5
else
    DNS_VERSION=1.2.6
fi
if [ -n "$6" ]; then
    FLANNEL_VERSION=$6
else
    FLANNEL_VERSION=v0.10.0-amd64
fi
## 拉取镜像
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:$K8S_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:$K8S_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:$K8S_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:$K8S_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:$DASHBOARD_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:$ETCD_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/pause:$PAUSE_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:$DNS_VERSION
docker pull registry.cn-hangzhou.aliyuncs.com/kubernetes_containers/flannel:$FLANNEL_VERSION
## 修改标签
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:$K8S_VERSION k8s.gcr.io/kube-controller-manager:$K8S_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:$K8S_VERSION k8s.gcr.io/kube-scheduler:$K8S_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:$K8S_VERSION k8s.gcr.io/kube-proxy:$K8S_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:$K8S_VERSION k8s.gcr.io kube-apiserver:$K8S_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:$DASHBOARD_VERSION k8s.gcr.io/kubernetes-dashboard-amd64:$DASHBOARD_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:$ETCD_VERSION k8s.gcr.io/etcd:$ETCD_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/pause:$PAUSE_VERSION k8s.gcr.io/pause:$PAUSE_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:$DNS_VERSION k8s.gcr.io/coredns:$DNS_VERSION
docker tag registry.cn-hangzhou.aliyuncs.com/kubernetes_containers/flannel:$FLANNEL_VERSION quay.io/coreos/flannel:$FLANNEL_VERSION
## 删除原始标签
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:$K8S_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:$K8S_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:$K8S_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:$K8S_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:$DASHBOARD_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:$ETCD_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/pause:$PAUSE_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:$DNS_VERSION
docker rmi registry.cn-hangzhou.aliyuncs.com/kubernetes_containers/flannel:$FLANNEL_VERSION

初始化kubernetes

出于对网络速度的考虑，我们使用了Flannel作为网络模型，不同网络模型的初始化参数可能不一样，请依据指导初始化

kubeadm init --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=<ip-address>

导出配置文件

导出配置文件是十分必要的，kubernetes会从当前操作用户的~/.kube目录下读取配置文件

# 对于普通用户
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
# 对于root用户
export KUBECONFIG=/etc/kubernetes/admin.conf

如果配置文件无法读取，您在接下来的操作当中可能会看到如下错误之一：

Unable to connect to the server: x509: certificate signed by unknown authority (possibly because of “crypto/rsa: verification error” while trying to verify candidate authority certificate “kubernetes”)

The connection to the server localhost:8080 was refused - did you specify the right host or port?

The connection to the server localhost:6443 was refused - did you specify the right host or port?

部署kubernetes网络模型

如果您选择了其他网络模型，请依据指导完成本步骤

sysctl net.bridge.bridge-nf-call-iptables=1
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

**部署NVIDIA设备插件**
docker pull nvidia/k8s-device-plugin:1.11
# 如果无法直接拉取镜像
# git clone https://github.com/NVIDIA/k8s-device-plugin.git && cd k8s-device-plugin
# docker build -t nvidia/k8s-device-plugin:1.11 .
docker run --security-opt=no-new-privileges --cap-drop=ALL --network=none -dit -v /var/lib/kubelet/device-plugins:/var/lib/kubelet/device-plugins nvidia/k8s-device-plugin:1.11

kubectl create -f https://raw.githubusercontent.com/NVIDIA/k8s-device-plugin/v1.11/nvidia-device-plugin.yml

**部署kubernetes dashboard**
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v1.10.1/src/deploy/recommended/kubernetes-dashboard.yaml

安装结束

至此，kubernetes已经成功在您的机器上安装，运行

kubectl get pods --all-namespaces

检视所有pod的运行情况

在下一篇文章当中，我们将会介绍如何部署第一个应用。