环境准备 

192.168.222.247  k8s-master centos 7.5

192.168.222.250   k8s-node1 centos 7.5

基础环境准备

1. 关闭防火墙

systemctl stop firewalld

systemctl disable firewalld

1. 关闭seliunx

sed -i 's/enforcing/disabled/' /etc/selinux/config

setenforce 0

1. 关闭swap

swapoff -a  $ 临时

vim /etc/fstab  $ 永久

1. 设置好主机名

hostnamectl set-hostname  k8s-master

hostnamectl set-hostname  k8s-node1

5.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

sysctl --system

如果不进行这一步的设置，kubadm init 自检时会报错

配置yum 源

cat > /etc/yum.repos.d/kubernetes.repo << EOF

[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

yum clean all

yum makecache

安装阿里云的镜像源

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-18.06.1.ce-3.el7

启动 docker

systemctl enable docker && systemctl start docker

docker --version  # 查看docker 版本

安装 kubeadm，kubelet和kubectl

yum install -y kubelet-1.13.3 kubeadm-1.13.3 kubectl-1.13.3

指定软件的安装版本 ，但是安装的时候会报错

No package kubernetes-cni=0.6.0 available.

解决方法

CNI是Container Network Interface的是一个标准的，通用的接口。现在容器平台：docker，kubernetes，mesos，容器网络解决方案：flannel，calico，weave。只要提供一个标准的接口，就能为同样满足该协议的所有容器平台提供网络功能，而CNI正是这样的一个标准接口协议。

yum 源安装导致版本冲突 ，解决方法寻找 yum 安装依赖的rpm 包，

包怎么找呢

参考k8s官方yum仓库配置， 我们可以在https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64/repodata/primary.xml配置文件中找到rpm包的下载链接

rpm包下载前缀是https://yum.kubernetes.io

pool/fe33057ffe95bfae65e2f269e1b05e99308853176e24a4d027bc082b471a07c0-kubernetes-cni-0.6.0-0.x86_64.rpm

<location href="../../pool/fe33057ffe95bfae65e2f269e1b05e99308853176e24a4d027bc082b471a07c0-kubernetes-cni-0.6.0-0.x86_64.rpm"/>

40ff4cf56f1b01f7415f0a4708e190cff5fbf037319c38583c52ae0469c8fcf3-kubeadm-1.11.1-0.x86_64.rpm

地址拼接：

https://yum.kubernetes.io + pool/fe33057ffe95bfae65e2f269e1b05e99308853176e24a4d027bc082b471a07c0 +  应用版本 如 kubernetes-cni-0.6.0-0.x86_64.rpm

找那些包呢

cri-tools-1.11.0-0.x86_64.rpm

kubectl-1.11.1-0.x86_64.rpm

socat-1.7.3.2-2.el7.x86_64.rpm

kubelet-1.11.1-0.x86_64.rpm

kubernetes-cni-0.6.0-0.x86_64.rpm

kubeadm-1.11.1-0.x86_64.rpm

socat-1.7.3.2-2.el7.x86_64.rpm 不能在配置文件中找到下载地址，直接使用 yum 安装

包的安装顺序呢

yum install socat -y

rpm -ivh  cri-tools-1.13.3-0.x86_64.rpm

rpm -ivh kubectl-1.13.3-0.x86_64.rpm

rpm -ivh kubelet-1.13.3-0.x86_64.rpm kubernetes-cni-0.6.0-0.x86_64.rpm

rpm -ivh kubeadm-1.13.3-0.x86_64.rpm

kubeadm 初始化 

kubeadm init \

 --apiserver-advertise-address=192.168.222.247 \

 --kubernetes-version v1.13.3 \

 --service-cidr=10.1.0.0/16\

 --pod-network-cidr=10.244.0.0/16

报错

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/kube-apiserver-amd64:v1.13.3]: exit status 1

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/kube-controller-manager-amd64:v1.13.3]: exit status 1

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/kube-scheduler-amd64:v1.13.3]: exit status 1

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/kube-proxy-amd64:v1.13.3]: exit status 1

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/pause:3.1]: exit status 1

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/etcd-amd64:3.2.24]: exit status 1

[ERROR ImagePull]: failed to pull image [k8s.gcr.io/coredns:1.1.3]: exit status 1

初始的镜像没有，×××，或者想办法提前下载好镜像，幸好阿里云提供下载的镜像地址 前缀：registry.cn-hangzhou.aliyuncs.com/google_containers

#coding:utf-8

#!/usr/bin/ python

import os

import subprocess

old_base_url = 'registry.cn-hangzhou.aliyuncs.com/google_containers/'

new_base_url = 'k8s.gcr.io/'

pull_list = [

'kube-apiserver-amd64:v1.13.3',

'kube-controller-manager-amd64:v1.13.3',

'kube-scheduler-amd64:v1.13.3',

'kube-proxy-amd64:v1.13.3',

'pause:3.1',

'etcd-amd64:3.2.18',

'coredns:1.1.3'

]

for container in pull_list:

old_container = os.path.join(old_base_url, container)

new_container = os.path.join(new_base_url, container)

print("开始拉取镜像%s......" % old_container)

os.system("docker pull {}".format(old_container))

print("==============镜像开始重命名==========")

os.system("docker tag %s %s" % (old_container, new_container))

print("开始删掉老镜像%s"%old_container)

os.system("docker rmi %s" % (old_container))

print("===================================")

kubeadm init 初始化

kubeadm init --apiserver-advertise-address=192.168.222.247  --kubernetes-version v1.13.3 --service-cidr=10.1.0.0/16  --pod-network-cidr=10.244.0.0/16

输出以下日志 

[init] using Kubernetes version: v1.13.3

[preflight] running pre-flight checks

[WARNING KubernetesVersion]: kubernetes version is greater than kubeadm version. Please consider to upgrade kubeadm. kubernetes version: 1.13.3. Kubeadm version: 1.11.x

I0421 02:16:48.942948   19072 kernel_validator.go:81] Validating kernel version

I0421 02:16:48.943124   19072 kernel_validator.go:96] Validating kernel config

[WARNING SystemVerification]: docker version is greater than the most recently validated version. Docker version: 18.06.1-ce. Max validated version: 17.03

[preflight/images] Pulling images required for setting up a Kubernetes cluster

[preflight/images] This might take a minute or two, depending on the speed of your internet connection

[preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull'

[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"

[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"

[preflight] Activating the kubelet service

[certificates] Generated ca certificate and key.

[certificates] Generated apiserver certificate and key.

[certificates] apiserver serving cert is signed for DNS names [k8s-master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.1.0.1 192.168.222.247]

[certificates] Generated apiserver-kubelet-client certificate and key.

[certificates] Generated sa key and public key.

[certificates] Generated front-proxy-ca certificate and key.

[certificates] Generated front-proxy-client certificate and key.

[certificates] Generated etcd/ca certificate and key.

[certificates] Generated etcd/server certificate and key.

[certificates] etcd/server serving cert is signed for DNS names [k8s-master localhost] and IPs [127.0.0.1 ::1]

[certificates] Generated etcd/peer certificate and key.

[certificates] etcd/peer serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.222.247 127.0.0.1 ::1]

[certificates] Generated etcd/healthcheck-client certificate and key.

[certificates] Generated apiserver-etcd-client certificate and key.

[certificates] valid certificates and keys now exist in "/etc/kubernetes/pki"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/admin.conf"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/controller-manager.conf"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/scheduler.conf"

[controlplane] wrote Static Pod manifest for component kube-apiserver to "/etc/kubernetes/manifests/kube-apiserver.yaml"

[controlplane] wrote Static Pod manifest for component kube-controller-manager to "/etc/kubernetes/manifests/kube-controller-manager.yaml"

[controlplane] wrote Static Pod manifest for component kube-scheduler to "/etc/kubernetes/manifests/kube-scheduler.yaml"

[etcd] Wrote Static Pod manifest for a local etcd instance to "/etc/kubernetes/manifests/etcd.yaml"

[init] waiting for the kubelet to boot up the control plane as Static Pods from directory "/etc/kubernetes/manifests"

[init] this might take a minute or longer if the control plane images have to be pulled

[apiclient] All control plane components are healthy after 49.545530 seconds

[uploadconfig] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace

[kubelet] Creating a ConfigMap "kubelet-config-1.13" in namespace kube-system with the configuration for the kubelets in the cluster

[markmaster] Marking the node k8s-master as master by adding the label "node-role.kubernetes.io/master=''"

[markmaster] Marking the node k8s-master as master by adding the taints [node-role.kubernetes.io/master:NoSchedule]

[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "k8s-master" as an annotation

[bootstraptoken] using token: e9tdub.hh2rmlrmbd83leja

[bootstraptoken] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials

[bootstraptoken] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token

[bootstraptoken] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster

[bootstraptoken] creating the "cluster-info" ConfigMap in the "kube-public" namespace

[addons] Applied essential addon: CoreDNS

[addons] Applied essential addon: kube-proxy

Your Kubernetes master 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/

You can now join any number of machines by running the following on each node

as root:

 kubeadm join 192.168.222.247:6443 --token e9tdub.hh2rmlrmbd83leja --discovery-token-ca-cert-hash sha256:e3c9f57bb590bd7d5086864239ded2beaa6c4c640a35835bd2ca4add68373499

### 奇怪

[WARNING KubernetesVersion]: kubernetes version is greater than kubeadm version. Please consider to upgrade kubeadm. kubernetes version: 1.13.3. Kubeadm version: 1.11.x

有可能是之前下载的 kubeadm 版本不对 

升级下版本 ，或者卸载重新安装 

yum upgrade kubeadm-1.13.3

kubeadm reset  # 重新初始化

然后重新kubeadm init 一下

使用kubectl工具： 操作

mkdir -p $HOME/.kube

cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

chown $(id -u):$(id -g) $HOME/.kube/config

查看集群状态 

ps 这里是1.11.1的图，后面是 升级后 1.13.3 

安装Pod网络插件（CNI）

kubectl apply -f

https://raw.githubusercontent.com/coreos/flannel/a70459be0084506e4ec919aa1c114638878db11b/Documentation/kube-flannel.yml