部署v1.22.1版的Kubernetes集群

部署v1.22.1版的Kubernetes集群

主机环境预设
本示例中的Kubernetes集群部署将基于以下环境进行。
OS: CentOS7.9
Kubernetes：v1.22.1
Container Runtime: Docker CE 20.10.8
每台机器配置（2G2核)
主机名称 ip
master 192.168.1.21
node1 192.168.1.22
node2 192.168.1.23

一.基础配置

1：分别在3台主机设置主机名称
hostnamectl set-hostname master
hostnamectl set-hostname node1
hostnamectl set-hostname node2
2:配置主机映射
cat < /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.21 master
192.168.1.22 node1
192.168.1.23 node2
EOF
3：3台主机配置、停防火墙、关闭Swap、关闭Selinux、设置内核、配置时间同步（配置完后建议重启一次）
systemctl stop firewalld
systemctl disable firewalld

swapoff -a 
sed -i 's/.*swap.*/#&/' /etc/fstab

setenforce  0 
sed -i "s/^SELINUX=enforcing/SELINUX=disabled/g" /etc/sysconfig/selinux 
sed -i "s/^SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config 
sed -i "s/^SELINUX=permissive/SELINUX=disabled/g" /etc/sysconfig/selinux 
sed -i "s/^SELINUX=permissive/SELINUX=disabled/g" /etc/selinux/config  
 
echo "* soft nofile 65536" >> /etc/security/limits.conf
echo "* hard nofile 65536" >> /etc/security/limits.conf
echo "* soft nproc 65536"  >> /etc/security/limits.conf
echo "* hard nproc 65536"  >> /etc/security/limits.conf
echo "* soft  memlock  unlimited"  >> /etc/security/limits.conf
echo "* hard memlock  unlimited"  >> /etc/security/limits.conf

服务端
1）在控制端配置时间同步服务
yum install chrony -y
2）编辑配置文件确认有以下配置

vim /etc/chrony.conf
--------------------------------
server ntp1.aliyun.com iburst
server ntp2.aliyun.com iburst
server 192.168.1.21 iburst
allow 192.168.1.0/24
--------------------------------

3）重启ntp服务，并配置开机自启动
systemctl restart chronyd.service
systemctl status chronyd.service
systemctl enable chronyd.service
systemctl list-unit-files |grep chronyd.service
4）设置时区，同步时间
timedatectl set-timezone Asia/Shanghai
chronyc sources
timedatectl status

客户端
1）安装包
yum install chrony -y
2）编辑配置文件确认有以下配置

vim /etc/chrony.conf
-------------------------------------
# 修改引用控制节点
server 192.168.1.21 iburst
-------------------------------------

3）重启chronyd服务，并配置开机自启动
systemctl restart chronyd.service
systemctl status chronyd.service
systemctl enable chronyd.service
systemctl list-unit-files |grep chronyd.service
4）设置时区，首次同步时间
timedatectl set-timezone Asia/Shanghai
chronyc sources
timedatectl status

二. 安装docker

1.常用包
yum install vim bash-completion net-tools gcc -y
2.使用aliyun源安装docker-ce
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
yum -y install docker-ce
systemctl enable docker.service
systemctl start docker.service
3.添加aliyundocker仓库加速器

tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": [
  "https://fl791z1h.mirror.aliyuncs.com"
],
"exec-opts": ["native.cgroupdriver=systemd"]
}
EOF

systemctl daemon-reload
systemctl restart docker.service

三.安装kubectl、kubelet、kubeadm

1.添加阿里kubernetes源

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

2.安装
yum install kubectl kubelet kubeadm
systemctl enable kubelet

四. 初始化k8s集群

1.初始化master节点（在master上完成如下操作）
[root@master ~]# kubeadm config images list
k8s.gcr.io/kube-apiserver:v1.22.1
k8s.gcr.io/kube-controller-manager:v1.22.1
k8s.gcr.io/kube-scheduler:v1.22.1
k8s.gcr.io/kube-proxy:v1.22.1
k8s.gcr.io/pause:3.5
k8s.gcr.io/etcd:3.5.0-0
k8s.gcr.io/coredns/coredns:v1.8.4
执行命令出现你要pull的镜像
我是先把这些pull下来
docker pull registry.aliyuncs.com/google_containers/kube-apiserver:v1.22.1
docker pull registry.aliyuncs.com/google_containers/kube-controller-manager:v1.22.1
docker pull registry.aliyuncs.com/google_containers/kube-scheduler:v1.22.1
docker pull registry.aliyuncs.com/google_containers/kube-proxy:v1.22.1
docker pull registry.aliyuncs.com/google_containers/pause:3.5
docker pull registry.aliyuncs.com/google_containers/etcd:3.5.0-0
docker pull registry.aliyuncs.com/google_containers/coredns:1.8.4(这个镜像得改名字才能正常运行起来)
docker tag registry.aliyuncs.com/google_containers/coredns:1.8.4 registry.aliyuncs.com/google_containers/coredns:v1.8.4

镜像pull下来就可以启动了

kubeadm init --kubernetes-version=1.22.1  \
--apiserver-advertise-address=192.168.1.21   \
--image-repository registry.aliyuncs.com/google_containers  \
--service-cidr=10.10.0.0/16 --pod-network-cidr=10.122.0.0/16

执行完会有一条
kubeadm join 192.168.1.21:6443 --token v2r5a4.veazy2xhzetpktfz
–discovery-token-ca-cert-hash sha256:daded8514c8350f7c238204979039ff9884d5b595ca950ba8bbce80724fd65d4
在node1和node2上面执行 （镜像下不来可以照着上面的做法）

[root@master ~]# mkdir -p $HOME/.kube
[root@master ~]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@master ~]# sudo chown $(id-u):$(id -g) $HOME/.kube/config
执行下面命令，使kubectl可以自动补充
[root@master01 ~]# source <(kubectl completion bash)

五.安装网络（依照自己的喜欢选择）

我在这里用的是flannel
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
当然也可以用calico
kubectl apply -f https://docs.projectcalico.org/manifests/calico.yaml

六.可以做个小测试

kubectl create deployment demoapp --image=ikubernetes/demoapp:v1.0
kubectl scale deployment/demoapp --replicas=3
kubectl create service nodeport demoapp --tcp=80:80

demoapp是一个web应用，因此，用户可以于集群外部通过“http://NodeIP:30528”这个URL访问demoapp上的应用，例如于集群外通过浏览器访问“http://192.168.1.22:30528”。