kubernetes的安裝

Kubernetes · 發表 2018-09-27 23:52:00

摘要：背景自己學習k8s叢集，無奈屌絲一枚，沒錢配置vpn服務，安裝k8s花費的時間太久了。為了小夥伴們可以快速安裝k8s，我花了點時間整理了這篇部落格，提供一個不用FQ就可以愉快安裝k8s叢集的方法。主機環境主機、IP規劃和網路規劃 ...

背景

自己學習k8s叢集，無奈屌絲一枚，沒錢配置vpn服務，安裝k8s花費的時間太久了。為了小夥伴們可以快速安裝k8s，我花了點時間整理了這篇部落格，提供一個不用FQ就可以愉快安裝k8s叢集的方法。

主機環境

主機、IP規劃和網路規劃

HOSTNAME	IP
master	10.8.3.91
node1	10.8.3.81
node2	10.8.3.82

k8s的pod網路採用 10.244.0.0/16 ，網路元件選擇flannel。

主機名設定

這裡使用centos7的hostnamectl設定主機名字， centos其他版本參考：ofollow,noindex">https://www.cnblogs.com/zhaojiedi1992/p/zhaojiedi_linux_043_hostname.html

#master節點
hostnamectlset-hostnamemaster && exec bash 
#node1節點
hostnamectlset-hostnamenode1 && exec bash 
#node2節點
hostnamectlset-hostnamenode2 && exec bash

hosts檔案設定

[root@master ~]# vim /etc/hosts 
# 新增如下3行 
10.4.3.91 master 
10.4.3.81 node1 
10.4.3.82 node2
# 其他的2個node節點也需要同樣操作

防火牆和selinux設定

[root@master ~]# sed -i "s/^SELINUX\=enforcing/SELINUX\=disabled/g" /etc/selinux/config
[root@master ~]# setenforce 0 
setenforce: SELinux is disabled
[root@master ~]# systemctl stop firewalld 
[root@master ~]# systemctl disable firewalld
# 其他的2個node節點也需要同樣操作

核心引數開啟

[root@master k8s_images]# echo "net.bridge.bridge-nf-call-ip6tables = 1" >>/etc/sysctl.conf 
[root@master k8s_images]# echo "net.bridge.bridge-nf-call-iptables = 1" >> /etc/sysctl.conf
[root@master k8s_images]# echo "net.ipv4.ip_forward=1" >> /etc/sysctl.conf 
[root@master k8s_images]# sysctl -p
# 其他的2個node節點也需要同樣操作

倉庫準備

# 備份舊的repo
[root@master ~]# cd /etc/yum.repos.d/
[root@master yum.repos.d]# ls
CentOS-Base.repoCentOS-Debuginfo.repoCentOS-Media.repoCentOS-Vault.repo
CentOS-CR.repoCentOS-fasttrack.repoCentOS-Sources.repo
[root@master yum.repos.d]# mkdir bak
[root@master yum.repos.d]# mv *.repo bak
[root@master yum.repos.d]# ls
bak
# 下載base,epel
[root@master yum.repos.d]# curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
[root@master yum.repos.d]# wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
# 下載k8s repo
[root@master yum.repos.d]# 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
# 其他的2個node節點也需要同樣操作

安裝k8s

docker和k8s軟體安裝

[root@master yum.repos.d]# yum install docker kubelet kubeadm kubectl
[root@master yum.repos.d]# systemctl enable kubelet && systemctl start kubelet
[root@master yum.repos.d]# systemctl enable docker && systemctl restart docker 

# 其他的2個node節點也需要同樣操作

docker加速配置


sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://mew8i5li.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

# 其他的2個node節點也需要同樣操作

曲線下載k8s所需的映象

這個我是在dockerhub上面的自動構建，原理就是拉去構建的映象，給這個映象打tag為google的tag，這樣我們在初始化叢集的時候就不會再去google去拉去映象檔案。

我的dockerhub：https://hub.docker.com/r/zhaojiedi1992

我的github倉庫：https://github.com/zhaojiedi1992/k8s_images

[root@master ~]# cd /root
[root@master ~]# mkdir git
[root@master ~]# cd git/
[root@master git]# git clone https://github.com/zhaojiedi1992/k8s_images.git
[root@master git]# cd k8s_images/
[root@master k8s_images]# ls
create_script.shpull_image_from_dockerhub_v1.10.6.shREADME.mdv1.10.6
pull_image_from_dockerhub.templatepull_image_from_dockerhub_v1.10.7.shtmp.txtv1.10.7
pull_image_from_dockerhub_v1.10.0.shpull_image_from_dockerhub_v1.10.8.shv1.10.0v1.10.8
pull_image_from_dockerhub_v1.10.1.shpull_image_from_dockerhub_v1.11.0.shv1.10.1v1.11
pull_image_from_dockerhub_v1.10.2.shpull_image_from_dockerhub_v1.11.1.shv1.10.2v1.11.0
pull_image_from_dockerhub_v1.10.3.shpull_image_from_dockerhub_v1.11.2.shv1.10.3v1.11.1
pull_image_from_dockerhub_v1.10.4.shpull_image_from_dockerhub_v1.11.3.shv1.10.4v1.11.2
pull_image_from_dockerhub_v1.10.5.shpull_image_from_dockerhub_v1.11.shv1.10.5v1.11.3
[root@master k8s_images]# chmod a+x *.sh

# 檢視安裝的k8s版本對應需要的映象
[root@master k8s_images]# kubeadm config images list --kubernetes-version=v1.11.3
k8s.gcr.io/kube-apiserver-amd64:v1.11.3
k8s.gcr.io/kube-controller-manager-amd64:v1.11.3
k8s.gcr.io/kube-scheduler-amd64:v1.11.3
k8s.gcr.io/kube-proxy-amd64:v1.11.3
k8s.gcr.io/pause:3.1
k8s.gcr.io/etcd-amd64:3.2.18
k8s.gcr.io/coredns:1.1.3

# 檢視指令碼的映象和需要拉去的是否一致。
[root@master k8s_images]# cat ./pull_image_from_dockerhub_v1.11.3.sh 
#!/bin/bash
gcr_name=k8s.gcr.io
myhub_name=zhaojiedi1992
# define images 
images=(
kube-apiserver-amd64:v1.11.3
kube-controller-manager-amd64:v1.11.3
kube-scheduler-amd64:v1.11.3
kube-proxy-amd64:v1.11.3
pause:3.1
etcd-amd64:3.2.18
coredns:1.1.3
)
for image in ${images[@]}; do 
docker pull $myhub_name/$image
docker tag $myhub_name/$image $gcr_name/$image
docker rmi $myhub_name/$image
done

# 確認上面的無錯誤，開始下載。
[root@master k8s_images]# ./pull_image_from_dockerhub_v1.11.3.sh 
[root@master k8s_images]# docker image ls 
REPOSITORY TAG IMAGE ID CREATED SIZE
k8s.gcr.io/pause 3.1 24440bb35d05 About an hour ago 742 kB
k8s.gcr.io/kube-proxy-amd64 v1.11.3 763b3c45ccd2 4 hours ago 97.8 MB
k8s.gcr.io/kube-scheduler-amd64 v1.11.3 8434ffab1549 5 hours ago 56.8 MB
k8s.gcr.io/kube-controller-manager-amd64 v1.11.3 3b0d0349c534 5 hours ago 155 MB
k8s.gcr.io/kube-apiserver-amd64 v1.11.3 306b76250de9 6 hours ago 187 MB
k8s.gcr.io/coredns 1.1.3 6b777875393d 6 hours ago 45.6 MB
k8s.gcr.io/etcd-amd64 3.2.18 7dc1bb5c1af1 6 hours ago 219 MB
# 其他的2個node節點也需要同樣操作

初始化k8s

[root@master k8s_images]#kubeadminit --pod-network-cidr=10.244.0.0/16 --kubernetes-version=v1.11.3
省略大量輸出
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 10.4.3.91:6443 --token 1ccx3e.jwbm8pbaq1awiz2z --discovery-token-ca-cert-hash sha256:838517f2d09d04d8ab1d736466311e32db26d2c5a9286fec37204b2de7923a67

客戶端設定

這裡kubectl客戶端的配置設定，我們直接設定到主節點上面來。

[root@master k8s_images]# mkdir -p $HOME/.kube
[root@master k8s_images]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
cp: overwrite ‘/root/.kube/config’? y
[root@master k8s_images]# sudo chown $(id -u):$(id -g) $HOME/.kube/config
[root@master k8s_images]# echo " kubeadm join 10.4.3.91:6443 --token 1ccx3e.jwbm8pbaq1awiz2z --discovery-token-ca-cert-hash sha256:838517f2d09d04d8ab1d736466311e32db26d2c5a9286fec37204b2de7923a67" >/root/k8s.json

安裝flannel網路元件

[root@master k8s_images]# kubectlapply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

node1加入叢集

[root@node1 k8s_images]#kubeadm join 10.4.3.91:6443 --token 1ccx3e.jwbm8pbaq1awiz2z --discovery-token-ca-cert-hash sha256:838517f2d09d04d8ab1d736466311e32db26d2c5a9286fec37204b2de7923a67

這個命令來自與主節點初始化的時候的輸出，上面已經儲存到主節點的/root/k8s.json。

檢視叢集狀態

[root@master k8s_images]# kubectl get nodes 
NAMESTATUSROLESAGEVERSION
masterReadymaster17mv1.11.3
node1Ready<none>8mv1.11.3
[root@master k8s_images]# kubectl get pod -n kube-system 
NAMEREADYSTATUSRESTARTSAGE
coredns-78fcdf6894-5zr251/1Running017m
coredns-78fcdf6894-82v6w1/1Running017m
etcd-master1/1Running07m
kube-apiserver-master1/1Running07m
kube-controller-manager-master1/1Running07m
kube-flannel-ds-amd64-5s9621/1Running04m
kube-flannel-ds-amd64-s2t5b1/1Running04m
kube-proxy-ccvdd1/1Running017m
kube-proxy-p2fbl1/1Running08m
kube-scheduler-master1/1Running07m

這個狀態需要等一段時間才能全是Running。好了，k8s叢集就安裝完畢了。