K8S-kubeadm安装

K8S-kubeadmin快速安装K8S集群

1.IP规划

节点	IP	组件
MASTER01（4C/6G,cpu核心数大于2）	192.168.80.20	docker、kubeadm、kubelet、kubectl、flannel
node01（2C/2G）	192.168.80.30	docker、kubeadm、kubelet、kubectl、flannel
node02（2C/2G）	192.168.80.35	docker、kubeadm、kubelet、kubectl、flannel
Harbor节点（hub.canyun.com）	192.168.80.50	docker、docker-compose、harbor-offline-v1.2.2

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
5、部署 Dashboard Web 页面，可视化查看Kubernetes资源
6、部署 Harbor 私有仓库，存放镜像资源

2.部署过程

2.1 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
sed -i 's/enforcing/disabled/' /etc/selinux/config
iptables -F && iptables -t nat -F && iptables -t mangle -F && iptables -X
swapoff -a						#交换分区必须要关闭
sed -ri 's/.*swap.*/#&/' /etc/fstab		#永久关闭swap分区，&符号在sed命令中代表上次匹配的结果
#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 master01
hostnamectl set-hostname node01
hostnamectl set-hostname node02

//所有节点修改hosts文件
cat >> /etc/hosts << EOF
192.168.80.20 master01
192.168.80.30 node01
192.168.80.35 node02
EOF

//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  

操作截图（以master01为例）

2.2 安装DOCKER

//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 -y docker-ce docker-ce-cli containerd.io

mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
  "registry-mirrors": ["https://6ijb8ubo.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  }
}
EOF
#使用Systemd管理的Cgroup来进行资源控制与管理，因为相对Cgroupfs而言，Systemd限制CPU、内存等资源更加简单和成熟稳定。
#日志使用json-file格式类型存储，大小为100M，保存在/var/log/containers目录下，方便ELK等日志系统收集和管理日志。

systemctl daemon-reload
systemctl restart docker.service
systemctl enable docker.service 

docker info | grep "Cgroup Driver"
Cgroup Driver: systemd

操作截图

2.3 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-1.20.11 kubeadm-1.20.11 kubectl-1.20.11

//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

操作截图（以master01为例）

2.4 部署K8S集群

//查看初始化需要的镜像
kubeadm config images list

//在 master 节点上传 v1.20.11.zip 压缩包至 /opt 目录
unzip v1.20.11.zip -d /opt/k8s
cd /opt/k8s/v1.20.11
for i in $(ls *.tar); do docker load -i $i; done

//复制镜像和脚本到 node 节点，并在 node 节点上执行脚本加载镜像文件
scp -r /opt/k8s root@node01:/opt
scp -r /opt/k8s root@node02:/opt

//master初始化kubeadm
方法一：
kubeadm config print init-defaults > /opt/kubeadm-config.yaml

cd /opt/
vim kubeadm-config.yaml
......
11 localAPIEndpoint:
12   advertiseAddress: 192.168.80.10		#指定master节点的IP地址
13   bindPort: 6443
......
34 kubernetesVersion: v1.20.11				#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kube-proxy调度方式改为ipvs模式

kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.log
#--experimental-upload-certs 参数可以在后续执行加入节点时自动分发证书文件，K8S V1.16版本开始替换为 --upload-certs
#tee kubeadm-init.log 用以输出日志

//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		


方法二：
kubeadm init \
--apiserver-advertise-address=192.168.80.10 \
--image-repository registry.aliyuncs.com/google_containers \
--kubernetes-version=v1.20.11 \
--service-cidr=10.96.0.0/16 \
--pod-network-cidr=10.244.0.0/16 \
--token-ttl=0
--------------------------------------------------------------------------------------------
初始化集群需使用kubeadm init命令，可以指定具体参数初始化，也可以指定配置文件初始化。
可选参数：
--apiserver-advertise-address：apiserver通告给其他组件的IP地址，一般应该为Master节点的用于集群内部通信的IP地址，0.0.0.0表示节点上所有可用地址
--apiserver-bind-port：apiserver的监听端口，默认是6443
--cert-dir：通讯的ssl证书文件，默认/etc/kubernetes/pki
--control-plane-endpoint：控制台平面的共享终端，可以是负载均衡的ip地址或者dns域名，高可用集群时需要添加
--image-repository：拉取镜像的镜像仓库，默认是k8s.gcr.io
--kubernetes-version：指定kubernetes版本
--pod-network-cidr：pod资源的网段，需与pod网络插件的值设置一致。Flannel网络插件的默认为10.244.0.0/16，Calico插件的默认值为192.168.0.0/16；
--service-cidr：service资源的网段
--service-dns-domain：service全域名的后缀，默认是cluster.local
--token-ttl：默认token的有效期为24小时，如果不想过期，可以加上 --token-ttl=0 这个参数
---------------------------------------------------------------------------------------------

方法二初始化后需要修改 kube-proxy 的 configmap，开启 ipvs
kubectl edit cm kube-proxy -n=kube-system
修改mode: ipvs


提示：
......
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

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 192.168.80.20:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:34242c82c6807c0e8ccbc9697aea749d89e1e736c19ab74ffd0dba6c1b379d5c 
	
	主节点执行：
  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config
  export KUBECONFIG=/etc/kubernetes/admin.conf
  从节点执行：
  kubeadm join 192.168.80.20:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:34242c82c6807c0e8ccbc9697aea749d89e1e736c19ab74ffd0dba6c1b379d5c 
	
//查看节点和服务状态
kubectl get nodes
NAME       STATUS     ROLES                  AGE     VERSION
master01   NotReady   control-plane,master   2m39s   v1.20.11
node01     NotReady   <none>                 46s     v1.20.11
node02     NotReady   <none>                 50s     v1.20.11
kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME                 STATUS      MESSAGE                                                                                       ERROR
controller-manager   Unhealthy   Get "http://127.0.0.1:10252/healthz": dial tcp 127.0.0.1:10252: connect: connection refused   
scheduler            Unhealthy   Get "http://127.0.0.1:10251/healthz": dial tcp 127.0.0.1:10251: connect: connection refused   
etcd-0               Healthy     {"health":"true"}
	
//修改kube-scheduler配置文件
vim /etc/kubernetes/manifests/kube-scheduler.yaml
 10 spec:
 11   containers:
 12   - command:
 13     - kube-scheduler
 14     - --authentication-kubeconfig=/etc/kubernetes/scheduler.conf
 15     - --authorization-kubeconfig=/etc/kubernetes/scheduler.conf
 16     - --bind-address=192.168.80.20        #修改为masterip
 17     - --kubeconfig=/etc/kubernetes/scheduler.conf
 18     - --leader-elect=true
 19 #    - --port=0                            #注释
............
 22     livenessProbe:
 23       failureThreshold: 8
 24       httpGet:
 25         host: 192.168.80.20       #修改为masterip
 26         path: /healthz
 27         port: 10259
............
 36     startupProbe:
 37       failureThreshold: 24
 38       httpGet:
 39         host: 192.168.80.20        #修改为masterip
 40         ipath: /healthz
 41         port: 10259
//修改controller-manager配置文件
 vim /etc/kubernetes/manifests/kube-controller-manager.yaml 
 11   containers:
 12   - command:
 13     - kube-controller-manager
 14     - --allocate-node-cidrs=true
 15     - --authentication-kubeconfig=/etc/kubernetes/controller-manager.conf
 16     - --authorization-kubeconfig=/etc/kubernetes/controller-manager.conf
 17     - --bind-address=192.168.80.20           #修改为masterip
 18     - --client-ca-file=/etc/kubernetes/pki/ca.crt
 19     - --cluster-cidr=10.244.0.0/16
 20     - --cluster-name=kubernetes
 21     - --cluster-signing-cert-file=/etc/kubernetes/pki/ca.crt
 22     - --cluster-signing-key-file=/etc/kubernetes/pki/ca.key
 23     - --controllers=*,bootstrapsigner,tokencleaner
 24     - --kubeconfig=/etc/kubernetes/controller-manager.conf
 25     - --leader-elect=true
 26 #    - --port=0                             # 注释
 ........................
 34     livenessProbe:
 35       failureThreshold: 8
 36       httpGet:
 37         host: 192.168.80.20                   #修改为masterip
 38         path: /healthz
 39         port: 10257
................................
 48     startupProbe:
 49       failureThreshold: 24
 50       httpGet:
 51         host: 192.168.80.20                  #修改为masterip
 52         path: /healthz
 53         port: 10257

操作截图

2.5 添加网络组件

//所有节点部署网络插件flannel
方法一：
//所有节点上传flannel镜像 flannel.tar 到 /opt 目录，master节点上传 kube-flannel.yml 文件
cd /opt
docker load < flannel.tar

//在 master 节点创建 flannel 资源
kubectl apply -f kube-flannel.yml 


方法二：
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml




//在master节点查看节点状态
kubectl get nodes

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-flannel-ds-amd64-kfhwf      1/1     Running   0          2m53s
kube-flannel-ds-amd64-qkdfh      1/1     Running   0          46m
kube-flannel-ds-amd64-vffxv      1/1     Running   0          2m56s
kube-proxy-558p8                 1/1     Running   0          2m53s
kube-proxy-nwd7g                 1/1     Running   0          2m56s
kube-proxy-qpz8t                 1/1     Running   0          71m
kube-scheduler-master            1/1     Running   0          70m


//测试 pod 资源创建
kubectl create deployment nginx --image=nginx

kubectl get pods -o wide
NAME                     READY   STATUS              RESTARTS   AGE   IP       NODE     NOMINATED NODE   READINESS GATES
nginx-6799fc88d8-96fr5   0/1     ContainerCreating   0          6s    <none>   node01   <none>           <none>
kubectl expose deployment nginx --port=80 --type=NodePort

//暴露端口提供服务

service/nginx exposed
kubectl get svc
NAME         TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE
kubernetes   ClusterIP   10.96.0.1        <none>        443/TCP        29m
nginx        NodePort    10.111.204.231   <none>        80:31590/TCP   5s


//测试访问
curl http://node01:32698

//扩展3个副本
kubectl scale deployment nginx --replicas=3

操作截图

2.6 部署 Dashboard

//在 master01 节点上操作
#上传 recommended.yaml 文件到 /opt/k8s 目录中
cd /opt/k8s
vim recommended.yaml
#默认Dashboard只能集群内部访问，修改Service为NodePort类型，暴露到外部：
kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 443
      targetPort: 8443
      nodePort: 30001     #添加
  type: NodePort          #添加
  selector:
    k8s-app: kubernetes-dashboard
	
kubectl apply -f recommended.yaml

#创建service account并绑定默认cluster-admin管理员集群角色
kubectl create serviceaccount dashboard-admin -n kube-system
kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')

#使用输出的token登录Dashboard
https://NodeIP:30001

操作截图

2.7 安装Harbor私有仓库

//修改主机名
hostnamectl set-hostname hub.canyun.com

//所有节点加上主机名映射
echo '192.168.80.50 hub.canyun.com' >> /etc/hosts

//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 -y docker-ce docker-ce-cli containerd.io

mkdir /etc/docker
cat > /etc/docker/daemon.json <<EOF
{
  "registry-mirrors": ["https://6ijb8ubo.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "insecure-registries": ["https://hub.canyun.com"]
}
EOF

systemctl start docker
systemctl enable docker


//所有 node 节点都修改 docker 配置文件，加上私有仓库配置
cat > /etc/docker/daemon.json <<EOF
{
  "registry-mirrors": ["https://6ijb8ubo.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "insecure-registries": ["https://hub.canyun.com"]
}
EOF

systemctl daemon-reload
systemctl restart docker


//安装 Harbor
//下载 harbor-offline-installer-v1.2.2.tgz 和 docker-compose 文件到 /opt 目录
cd /opt
wget http://harbor.orientsoft.cn/harbor-1.2.2/harbor-offline-installer-v1.2.2.tgz
curl -L https://github.com/docker/compose/releases/download/1.21.1/docker-compose-`uname -s`-`uname -m` -o /usr/local/bin/docker-compose

chmod +x /usr/local/bin/docker-compose

tar zxvf harbor-offline-installer-v1.2.2.tgz
cd harbor/
vim harbor.cfg
5  hostname = hub.canyun.com
9  ui_url_protocol = https
24 ssl_cert = /data/cert/server.crt
25 ssl_cert_key = /data/cert/server.key
59 harbor_admin_password = Harbor12345


//生成证书
mkdir -p /data/cert
cd /data/cert
#生成私钥
openssl genrsa -des3 -out server.key 2048
输入两遍密码：123456

#生成证书签名请求文件
openssl req -new -key server.key -out server.csr
输入私钥密码：123456
输入国家名：CN
输入省名：BJ
输入市名：BJ
输入组织名：CANYUN
输入机构名：CANYUN
输入域名：hub.canyun.com
输入管理员邮箱：admin@canyun.com
其它全部直接回车

#备份私钥
cp server.key server.key.org

#清除私钥密码
openssl rsa -in server.key.org -out server.key
输入私钥密码：123456

#签名证书
openssl x509 -req -days 1000 -in server.csr -signkey server.key -out server.crt

chmod +x /data/cert/*

cd /opt/harbor/
./install.sh

浏览器访问：https://hub.canyun.com
(宿主机可以直接访问192.168.80.50)
用户名：admin
密码：Harbor12345

//在一个node节点上登录harbor
docker login -u admin -p Harbor12345 https://hub.canyun.com

//上传镜像
docker tag nginx:latest hub.canyun.com/library/nginx:v1
docker push hub.canyun.com/library/nginx:v1

//在master节点上删除之前创建的nginx资源
kubectl delete deployment nginx



#将cluster-admin角色权限授予用户system:anonymous
kubectl create clusterrolebinding cluster-system-anonymous --clusterrole=cluster-admin --user=system:anonymous


########### 内核参数优化方案 ##########
cat > /etc/sysctl.d/kubernetes.conf <<EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
net.ipv4.tcp_tw_recycle=0
vm.swappiness=0									#禁止使用 swap 空间，只有当系统内存不足（OOM）时才允许使用它
vm.overcommit_memory=1							#不检查物理内存是否够用
vm.panic_on_oom=0								#开启 OOM
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963							#指定最大文件句柄数
fs.nr_open=52706963								#仅4.4以上版本支持
net.ipv6.conf.all.disable_ipv6=1
net.netfilter.nf_conntrack_max=2310720
EOF

操作截图