快速安装及搭建k8s集群

1、准备工作

服务器环境

主机名	操作系统	IP地址
master	Centos7.4	192.168.32.100
node1	Centos7.4	192.168.32.101
node2	Centos7.4	192.168.32.102

关闭防火墙和swap

systemctl disable firewalld
systemctl stop firewalld
setenforce 0
swapoff -a #实时动态关闭
sed -i '/ swap / s/^/#/' /etc/fstab #禁止重启后自动开启

配置内核参数

cat > /etc/sysctl.d/k8s.conf << EOF
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1    
vm.swappiness=0
EOF

sysctl --system

修改主机名（三台服务器都针对自己的角色进行此操作）

hostnamectl set-hostname master  //192.168.32.100
hostnamectl set-hostname node1  //192.168.32.101
hostnamectl set-hostname node2  //192.168.32.102

修改/etc/hosts文件

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.32.100 master
192.168.32.101 node1
192.168.32.102 node2

时间校对

[root@master ~]# yum -y install ntp*
[root@master ~]# ntpdate ntp1.aliyun.com

[root@master ~]# hwclock

2、master安装kubernetes

配置docker镜像

[root@master ~]# wget -O /etc/yum.repos.d/docker-ce.repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

配置kubernetes仓库

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

[root@master yum.repos.d]# wget https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
[root@master yum.repos.d]# rpm --import rpm-package-key.gpg
[root@master yum.repos.d]# yum repolist

拷贝到node1和node2
[root@master yum.repos.d]# scp CentOS-Base.repo docker-ce.repo kubernetes.repo node1:/etc/yum.repos.d/

安装docker和kubelet

[root@master ~]# yum -y install docker-ce kubelet kubeadm kubectl

修改环境变量

[root@master ~]# vim /usr/lib/systemd/system/docker.service
添加2行：
Environment=“HTTPS_PROXY=http://www.ik8s.io:10080”
Environment=“NO_PROXY=127.0.0.0/8,172.0.0.0/16”

[root@master ~]# systemctl daemon-reload

启动docker并设置开机启动

[root@master ~]# systemctl start docker
[root@master ~]# systemctl enable docker

修改docker的cgroup驱动

vi /etc/docker/daemon.json
写入以下内容

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

重启docker

systemctl restart docker
systemctl status docker

查看输出是否是1

[root@master ~]# cat /proc/sys/net/bridge/bridge-nf-call-ip6tables
[root@master ~]# cat /proc/sys/net/bridge/bridge-nf-call-iptables

[root@master ~]# rpm -ql kubelet
/etc/kubernetes/manifests ----清单目录
/etc/sysconfig/kubelet ----配置文件
/etc/systemd/system/kubelet.service
/usr/bin/kubelet ----主程序

设置开机启动

[root@master ~]# systemctl enable kubelet

kubeadm初始化准备

在使用kubeadm init命令初始化时报错，pull镜像失败，因为镜像在国外，所以需要我们可以下载国内的镜像，然后再修改tag。
kubeadm config images list 命令查看需要哪些镜像**

下载镜像（其他的镜像修改后面的名字即可）
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.19.4
修改tag
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.18.3 k8s.gcr.io/kube-proxy:v1.19.4

[root@master ~]# vim /etc/sysconfig/kubelet
KUBELET_EXTRA_ARGS="–fail-swap-on=false"

初始化

[root@master ~]# kubeadm init --kubernetes-version=v1.19.4 --pod-network-cidr=10.10.0.0/16 --service-cidr=10.20.0.0/16 --ignore-preflight-errors=Swap

保存好此命令（加集群）
kubeadm join 192.168.32.100:6443 --token m8zgnk.1qeouhrtgdc5l35n
–discovery-token-ca-cert-hash sha256:d5bb2b9b84e9b8a84cb826cb5cc806bb645eb415596ddaa3b7cde1f56ecabff0
netstat -ntlp 查看监听端口

[root@master ~]# mkdir -p $HOME/.kube
[root@master ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@master ~]# sudo chown $(id -u): $(id -g) $HOME/.kube/config

查看组件是否健康

[root@master ~]# kubectl get cs

如果kubectl get cs时显示controller-manager和scheduler状态unhealthy，则修改kube-controller-manager.yaml和kube-scheduler.yaml，将port=0这一行注释掉，然后重启kubelet

systemctl restart kubelet

查看节点

[root@master ~]# kubectl get nodes

安装weave

[root@master ~]# kubectl apply -f “https://cloud.weave.works/k8s/net?k8s-version=1.19.4”

查看节点信息

[root@master ~]# kubectl get nodes

查看pod运行情况

[root@master ~]# kubectl get pods -n kube-system

复制配置文件到node1、node2

[root@master ~]# scp /usr/lib/systemd/system/docker.service node1:/usr/lib/systemd/system/docker.service

[root@master ~]# scp /etc/sysconfig/kubelet node1:/etc/sysconfig/

[root@master ~]# scp /usr/lib/systemd/system/docker.service node2:/usr/lib/systemd/system/docker.service

[root@master ~]# scp /etc/sysconfig/kubelet node2:/etc/sysconfig/

3、node1、node2部署

[root@node1 ~]# wget https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
[root@node1 ~]# rpm --import rpm-package-key.gpg
[root@node1 ~]# yum -y install docker-ce kubelet kubeadm
[root@node1 ~]# systemctl start docker
[root@node1 ~]# systemctl enable docker kubelet
[root@node1 ~]# docker info

添加集群

[root@node1 ~]# kubeadm join 192.168.32.100:6443 --token m8zgnk.1qeouhrtgdc5l35n
–discovery-token-ca-cert-hash sha256:d5bb2b9b84e9b8a84cb826cb5cc806bb645eb415596ddaa3b7cde1f56ecabff0

查看节点

[root@master ~]# kubectl get nodes

查看pod

[root@master ~]# kubectl get pods -n kube-system -o wide