kubeadm搭建1.20.7版本k8s
资源
| 服务器名称 | ip地址 | 服务 |
|---|---|---|
| master1（2C/4G，cpu核心数要求大于2） | 192.168.100.10 | docker、kubeadm、kubelet、kubectl、flannel |
| node01（2C/2G） | 192.168.100.30 | docker、kubeadm、kubelet、kubectl、flannel |
| node02（2C/2G） | 192.168.100.40 | docker、kubeadm、kubelet、kubectl、flannel |
| node03（2C/2G） | 192.168.100.50 | docker、kubeadm、kubelet、kubectl、flannel |
1、在所有节点上安装Docker和kubeadm
2、部署Kubernetes Master
3、部署容器网络插件
4、部署 Kubernetes Node，将节点加入Kubernetes集群中
环境准备
所有节点，关闭防火墙规则，关闭selinux，关闭swap交换
systemctl stop firewalld
systemctl disable firewalld
setenforce 0
iptables -F
swapoff -a #交换分区必须要关闭
#加载 ip_vs 模块
for i in $(ls /usr/lib/modules/$(uname -r)/kernel/net/netfilter/ipvs|grep -o "^[^.]*");do echo $i; /sbin/modinfo -F filename $i >/dev/null 2>&1 && /sbin/modprobe $i;done
修改主机名
hostnamectl set-hostname master1
hostnamectl set-hostname node01
hostnamectl set-hostname node02
hostnamectl set-hostname node03
免密打通
ssh-keygen -t rsa
cd ~/.ssh/
ssh-copy-id -i id_rsa.pub [email protected]
ssh-copy-id -i id_rsa.pub [email protected]
ssh-copy-id -i id_rsa.pub [email protected]
所有节点修改hosts文件
vim /etc/hosts
192.168.100.10 master1
192.168.100.30 node01
192.168.100.40 node02
192.168.100.50 node03
scp /etc/hosts node01:/etc
scp /etc/hosts node02:/etc
scp /etc/hosts node03:/etc
调整内核参数
cat > /etc/sysctl.d/kubernetes.conf << EOF
#开启网桥模式，可将网桥的流量传递给iptables链
net.bridge.bridge-nf-call-ip6tables=1
net.bridge.bridge-nf-call-iptables=1
#关闭ipv6协议
net.ipv6.conf.all.disable_ipv6=1
net.ipv4.ip_forward=1
EOF
## 生效参数
sysctl --system
所有节点安装docker
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 install docker-ce docker-ce-cli containerd.io -y
mkdir /etc/docker
cat > /etc/docker/daemon.json <systemctl daemon-reload
systemctl restart docker.service
systemctl enable docker.service
docker info | grep "Cgroup Driver"
#Cgroup Driver: systemd
所有节点安装kubeadm，kubelet和kubectl
定义kubernetes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=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
yum install -y kubelet-1.20.7 kubeadm-1.20.7 kubectl-1.20.7
开机自启kubelet
systemctl enable kubelet.service
#K8S通过kubeadm安装出来以后都是以Pod方式存在，即底层是以容器方式运行，所以kubelet必须设置开机自启
查看初始化需要的镜像
kubeadm config images list
导入k8s镜像
方法一：无k8s镜像搭建方法
master上执行
下载k8s-1.20.7镜像
kubeadm config images pull --kubernetes-version v1.20.7 --image-repository registry.aliyuncs.com/google_containers
docker images
镜像重新打tag
docker tag registry.aliyuncs.com/google_containers/kube-proxy:v1.20.7 k8s.gcr.io/kube-proxy:v1.20.7
docker tag registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.7 k8s.gcr.io/kube-apiserver:v1.20.7
docker tag registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.7 k8s.gcr.io/kube-controller-manager:v1.20.7
docker tag registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.7 k8s.gcr.io/kube-scheduler:v1.20.7
docker tag registry.aliyuncs.com/google_containers/etcd:3.4.13-0 k8s.gcr.io/etcd:3.4.13-0
docker tag registry.aliyuncs.com/google_containers/coredns:1.7.0 k8s.gcr.io/coredns:1.7.0
docker tag registry.aliyuncs.com/google_containers/pause:3.2 k8s.gcr.io/pause:3.2
导出k8s镜像
mkdir kubeadm-basic.images
cd kubeadm-basic.images
docker save k8s.gcr.io/kube-proxy:v1.20.7 -o kube-proxy.tar
docker save k8s.gcr.io/kube-apiserver:v1.20.7 -o kube-apiserver.tar
docker save k8s.gcr.io/kube-controller-manager:v1.20.7 -o kube-controller-manager.tar
docker save k8s.gcr.io/kube-scheduler:v1.20.7 -o kube-scheduler.tar
docker save k8s.gcr.io/etcd:3.4.13-0 -o etcd.tar
docker save k8s.gcr.io/coredns:1.7.0 -o coredns.tar
docker save k8s.gcr.io/pause:3.2 -o pause.tar
打包k8s镜像
tar -czvf kubeadm-basic.images.tar.gz kubeadm-basic.images/*
复制镜像和脚本到 node 节点，并在 node 节点上执行脚本 bash /opt/load-images.sh
scp -r kubeadm-basic.images.tar.gz root@node01:/opt
scp -r kubeadm-basic.images.tar.gz root@node02:/opt
scp -r kubeadm-basic.images.tar.gz root@node03:/opt
所有节点上执行
cd /opt
tar -zxvf kubeadm-basic.images.tar.gz
for i in $(ls /opt/kubeadm-basic.images/*.tar); do docker load -i $i; done
方法二：已有k8s镜像搭建方法
在 master 节点上传 kubeadm-basic.images.tar.gz 压缩包至 /opt 目录
cd /opt
tar zxvf kubeadm-basic.images.tar.gz
for i in $(ls /opt/kubeadm-basic.images/*.tar); do docker load -i $i; done
复制镜像和脚本到 node 节点
scp -r kubeadm-basic.images root@node01:/opt
scp -r kubeadm-basic.images root@node02:/opt
scp -r kubeadm-basic.images root@node03:/opt
所有节点上执行
cd /opt
for i in $(ls /opt/kubeadm-basic.images/*.tar); do docker load -i $i; done
master上执行
初始化kubeadm
kubeadm config print init-defaults > /opt/kubeadm-config.yaml
cd /opt/
vim kubeadm-config.yaml
......
11 localAPIEndpoint:
12 advertiseAddress: 192.168.100.10 #指定master节点的IP地址
13 bindPort: 6443
......
34 kubernetesVersion: v1.20.7 #指定kubernetes版本号
35 networking:
36 dnsDomain: cluster.local
37 podSubnet: "10.244.0.0/16" #指定pod网段，10.244.0.0/16用于匹配flannel默认网段
38 serviceSubnet: 10.96.0.0/16 #指定service网段
39 scheduler: {}
--- #末尾再添加以下内容
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: ipvs #把默认的service调度方式改为ipvs模式
ipvs:
strictARP: true
scheduler: rr
kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.log
#--upload-certs 参数可以在后续执行加入节点时自动分发证书文件，k8sV1.15版本以下替换为 --experimental-upload-certs
#tee kubeadm-init.log 用以输出日志
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
Alternatively, if you are the root user, you can run:
export KUBECONFIG=/etc/kubernetes/admin.conf
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 192.168.100.10:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:8be27369ddd5c8cad17eef27825754d921d71c58d1cc9c56cee4988fd86417ef
查看 kubeadm-init 日志
less kubeadm-init.log
kubernetes配置文件目录
ls /etc/kubernetes/
存放ca等证书和密码的目录
ls /etc/kubernetes/pki
创建k8s config
mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config
所有节点上执行
kubeadm join 192.168.100.10:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:8be27369ddd5c8cad17eef27825754d921d71c58d1cc9c56cee4988fd86417ef
master上执行
自动补全
echo "source <(kubectl completion bash)" /etc/profile
source /etc/profile
部署网络插件flannel
创建 flannel 资源
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
kubectl apply -f kube-flannel.yml
##注意flannel镜像名称和yaml内的是否一致
## 同步到所有节点
scp /opt/cni/bin/flannel node01:/opt/cni/bin
scp /opt/cni/bin/flannel node02:/opt/cni/bin
scp /opt/cni/bin/flannel node03:/opt/cni/bin
在master节点查看节点状态（需要等几分钟）
kubectl get nodes
NAME STATUS ROLES AGE VERSION
master1 Ready control-plane,master 78m v1.20.7
node01 Ready 78m v1.20.7
node02 NotReady 78m v1.20.7
node03 NotReady 78m v1.20.7
kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-bccdc95cf-c9w6l 1/1 Running 0 71m
coredns-bccdc95cf-nql5j 1/1 Running 0 71m
etcd-master 1/1 Running 0 71m
kube-apiserver-master 1/1 Running 0 70m
kube-controller-manager-master 1/1 Running 0 70m
kube-proxy-558p8 1/1 Running 0 2m53s
kube-proxy-nwd7g 1/1 Running 0 2m56s
kube-proxy-wd87d 1/1 Running 0 2m54s
kube-proxy-qpz8t 1/1 Running 0 71m
kube-scheduler-master 1/1 Running 0 70m
kubectl get pods -n kube-flannel
NAME READY STATUS RESTARTS AGE
kube-flannel-ds-2k5b9 1/1 Running 0 2m53s
kube-flannel-ds-fhx2c 1/1 Running 0 2m55s
kube-flannel-ds-g6z6q 1/1 Running 0 2m50s
kube-flannel-ds-nkrrj 1/1 Running 0 2m51s
验证
node节点上 登录到镜像仓库，获取镜像
docker login -u lp1078802338 -p registry.cn-hangzhou.aliyuncs.com
创建pod
kubectl create deployment nginx-deployment --image=registry.cn-hangzhou.aliyuncs.com/lp-k8s-prometheus/nginx:v1 --replicas=1
## 最好看一下pod在哪个节点上，然后登录node 使用docker拉取，不然会很慢
kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-deployment 1/1 Running 0 5m49s 10.244.1.2 node01
##node节点上执行
docker pull registry.cn-hangzhou.aliyuncs.com/lp-k8s-prometheus/nginx:v1
v1: Pulling from lp-k8s-prometheus/nginx
a2abf6c4d29d: Pull complete
a9edb18cadd1: Pull complete
589b7251471a: Pull complete
186b1aaa4aa6: Pull complete
b4df32aa5a72: Pull complete
a0bcbecc962e: Pull complete
docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
registry.cn-hangzhou.aliyuncs.com/lp-k8s-prometheus/nginx v1 605c77e624dd 23 months ago 141MB
##master上执行
kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/nginx-deployment-799b5654d5-b8nqv 1/1 Running 0 27s 10.244.1.3 node01
将pod的server类型改成NodePort
kubectl expose deployment nginx-deployment --port=80 --type=NodePort
kubectl get pod,svc -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/nginx-deployment-799b5654d5-b8nqv 1/1 Running 0 27s 10.244.1.3 node01
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/kubernetes ClusterIP 10.96.0.1 443/TCP 70m
service/nginx-deployment NodePort 10.97.191.117 80:30619/TCP 8s app=nginx-deployment
打开浏览器验证
http://node01:30619