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1 搭建K8s集群

1.1 版本统一

Docker       18.09.0

---

kubeadm-1.14.0-0

kubelet-1.14.0-0

kubectl-1.14.0-0

---

k8s.gcr.io/kube-apiserver:v1.14.0

k8s.gcr.io/kube-controller-manager:v1.14.0

k8s.gcr.io/kube-scheduler:v1.14.0

k8s.gcr.io/kube-proxy:v1.14.0

k8s.gcr.io/pause:3.1

k8s.gcr.io/etcd:3.3.10

k8s.gcr.io/coredns:1.3.1

---

calico:v3.9

1.2 准备3台centos

大家根据自己的情况来准备centos7的虚拟机。

要保证彼此之间能够ping通，也就是处于同一个网络中，虚拟机的配置要求上面也描述。

1.3 更新并安装依赖

yum -y update

yum install -y conntrack ipvsadm ipset jq sysstat curl iptables libseccomp

1.4 安装Docker

指定安装docker版本：yum install -y docker-ce-18.09.0 docker-ce-cli-18.09.0 containerd.io

1.5 修改hosts文件

# 设置master的hostname，并且修改hosts文件

sudo hostnamectl set-hostname m

vi /etc/hosts

192.168.8.51 m

192.168.8.61 w1

192.168.8.62 w2


# 设置worker01/02的hostname，并且修改hosts文件

sudo hostnamectl set-hostname w1

sudo hostnamectl set-hostname w2

vi /etc/hosts

192.168.8.51 m

192.168.8.61 w1

192.168.8.62 w2

1.6 系统基础前提配置

# (1)关闭防火墙

systemctl stop firewalld && systemctl disable firewalld

# (2)关闭selinux

setenforce 0

sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config

# (3)关闭swap

swapoff -a

sed -i '/swap/s/^\(.*\)$/#\1/g' /etc/fstab

# (4)配置iptables的ACCEPT规则

iptables -F && iptables -X && iptables -F -t nat && iptables -X -t nat && iptables -P FORWARD ACCEPT

# (5)设置系统参数

cat <<EOF >  /etc/sysctl.d/k8s.conf

net.bridge.bridge-nf-call-ip6tables = 1

net.bridge.bridge-nf-call-iptables = 1

EOF

sysctl --system

1.7 Installing kubeadm, kubelet and kubectl

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


yum install -y kubeadm-1.14.0-0 kubelet-1.14.0-0 kubectl-1.14.0-0


# docker

vi /etc/docker/daemon.json

    "exec-opts": ["native.cgroupdriver=systemd"],

systemctl restart docker

# kubelet

sed -i "s/cgroup-driver=systemd/cgroup-driver=cgroupfs/g" /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

systemctl enable kubelet && systemctl start kubelet

1.8 proxy/pause/scheduler等国内镜像

k8s.gcr.io/kube-apiserver:v1.14.0

k8s.gcr.io/kube-controller-manager:v1.14.0

k8s.gcr.io/kube-scheduler:v1.14.0

k8s.gcr.io/kube-proxy:v1.14.0

k8s.gcr.io/pause:3.1

k8s.gcr.io/etcd:3.3.10

k8s.gcr.io/coredns:1.3.1
  • 创建kubeadm.sh脚本，用于拉取镜像/打tag/删除原有镜像
#!/bin/bash

set -e

KUBE_VERSION=v1.14.0

KUBE_PAUSE_VERSION=3.1

ETCD_VERSION=3.3.10

CORE_DNS_VERSION=1.3.1

GCR_URL=k8s.gcr.io

ALIYUN_URL=registry.cn-hangzhou.aliyuncs.com/google_containers

images=(kube-proxy:${KUBE_VERSION}

kube-scheduler:${KUBE_VERSION}

kube-controller-manager:${KUBE_VERSION}

kube-apiserver:${KUBE_VERSION}

pause:${KUBE_PAUSE_VERSION}

etcd:${ETCD_VERSION}

coredns:${CORE_DNS_VERSION})

for imageName in ${images[@]} ; do

  docker pull $ALIYUN_URL/$imageName

  docker tag  $ALIYUN_URL/$imageName $GCR_URL/$imageName

  docker rmi $ALIYUN_URL/$imageName

done
  • 运行脚本和查看镜像
# 运行脚本

sh ./kubeadm.sh

# 查看镜像

docker images
  • 将这些镜像推送到自己的阿里云仓库【可选，根据自己实际的情况】
# 登录自己的阿里云仓库

docker login --username=xxx registry.cn-hangzhou.aliyuncs.com


#!/bin/bash

set -e

KUBE_VERSION=v1.14.0

KUBE_PAUSE_VERSION=3.1

ETCD_VERSION=3.3.10

CORE_DNS_VERSION=1.3.1

GCR_URL=k8s.gcr.io

ALIYUN_URL=xxx

images=(kube-proxy:${KUBE_VERSION}

kube-scheduler:${KUBE_VERSION}

kube-controller-manager:${KUBE_VERSION}

kube-apiserver:${KUBE_VERSION}

pause:${KUBE_PAUSE_VERSION}

etcd:${ETCD_VERSION}

coredns:${CORE_DNS_VERSION})

for imageName in ${images[@]} ; do

  docker tag $GCR_URL/$imageName $ALIYUN_URL/$imageName

  docker push $ALIYUN_URL/$imageName

  docker rmi $ALIYUN_URL/$imageName

done

1.9 kube init初始化master

01-进行一系列检查，以确定这台机器可以部署kubernetes

02-生成kubernetes对外提供服务所需要的各种证书可对应目录

/etc/kubernetes/pki/*

03-为其他组件生成访问kube-ApiServer所需的配置文件

    ls /etc/kubernetes/

    admin.conf  controller-manager.conf  kubelet.conf  scheduler.conf

04-为 Master组件生成Pod配置文件。

    ls /etc/kubernetes/manifests/*.yaml

    kube-apiserver.yaml

    kube-controller-manager.yaml

    kube-scheduler.yaml

05-生成etcd的Pod YAML文件。

    ls /etc/kubernetes/manifests/*.yaml

    kube-apiserver.yaml

    kube-controller-manager.yaml

    kube-scheduler.yaml

	etcd.yaml

06-一旦这些 YAML 文件出现在被 kubelet 监视的/etc/kubernetes/manifests/目录下，kubelet就会自动创建这些yaml文件定义的pod，即master组件的容器。master容器启动后，kubeadm会通过检查localhost：6443/healthz这个master组件的健康状态检查URL，等待master组件完全运行起来

07-为集群生成一个bootstrap token

08-将ca.crt等 Master节点的重要信息，通过ConfigMap的方式保存在etcd中，工后续部署node节点使用

09-最后一步是安装默认插件，kubernetes默认kube-proxy和DNS两个插件是必须安装的


# 本地有镜像

kubeadm init --kubernetes-version=1.14.0 --apiserver-advertise-address=192.168.3.160 --pod-network-cidr=10.244.0.0/16

【若要重新初始化集群状态：kubeadm reset，然后再进行上述操作】

记得保存好最后kubeadm join的信息

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 192.168.3.160:6443 --token zt2df2.v866n2bw2pyjyq1o \

    --discovery-token-ca-cert-hash sha256:9537b7e84fab63dfa10bf5710563bd762c25ec184f288c4bce5818c71fef0183

此时kubectl cluster-info查看一下是否成功

kubectl get pods -n kube-system


curl -k https://localhost:6443/healthz

1.10 部署calico网络插件

# 在k8s中安装calico

kubectl apply -f https://docs.projectcalico.org/v3.9/manifests/calico.yaml

# 确认一下calico是否安装成功

kubectl get pods --all-namespaces -w

1.11 kube join

kubeadm join 192.168.0.51:6443 --token yu1ak0.2dcecvmpozsy8loh \

    --discovery-token-ca-cert-hash sha256:5c4a69b3bb05b81b675db5559b0e4d7972f1d0a61195f217161522f464c307b0


kubectl get nodes

NAME                   STATUS   ROLES    AGE     VERSION

master-kubeadm-k8s     Ready    master   19m     v1.14.0

worker01-kubeadm-k8s   Ready    <none>   3m6s    v1.14.0

worker02-kubeadm-k8s   Ready    <none>   2m41s   v1.14.0

1.12 再次体验Pod

cat > pod_nginx_rs.yaml <<EOF

apiVersion: apps/v1

kind: ReplicaSet

metadata:

  name: nginx

  labels:

    tier: frontend

spec:

  replicas: 3

  selector:

    matchLabels:

      tier: frontend

  template:

    metadata:

      name: nginx

      labels:

        tier: frontend

    spec:

      containers:

      - name: nginx

        image: nginx

        ports:

        - containerPort: 80

EOF


kubectl apply -f pod_nginx_rs.yaml


kubectl get pods

kubectl get pods -o wide

kubectl describe pod nginx


kubectl scale rs nginx --replicas=5

kubectl get pods -o wide


kubectl delete -f pod_nginx_rs.yaml
05-12 13:05
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