目录

一、部署 CoreDNS

1.1.在所有 node 节点上操作

1.2.在 master01 节点上操作

1.3.DNS 解析测试

二、master02 节点部署

2.1.从 master01 节点上拷贝证书文件、各master组件的配置文件和服务管理文件到 master02 节点

2.2.修改配置文件kube-apiserver中的IP

2.3.在 master02 节点上启动各服务并设置开机自启

2.4./查看node节点状态

三、负载均衡部署

3.1.配置nginx的官方在线yum源，配置本地nginx的yum源

3.2.修改nginx配置文件，配置四层反向代理负载均衡，指定k8s群集2台master的节点ip和6443端口

3.3.检查配置文件语法

3.4.部署keepalived服务

3.5.创建nginx状态检查脚本 

3.6.启动keepalived服务（一定要先启动了nginx服务，再启动keepalived服务）

3.7.修改node节点上的bootstrap.kubeconfig,kubelet.kubeconfig配置文件为VIP

3.8.在 lb01 上查看 nginx 和 node 、 master 节点的连接状态

3.9.在 master01 节点上操作

---

一、部署 CoreDNS

CoreDNS：可以为集群中的 service 资源创建一个域名 与 IP 的对应关系解析

1.1.在所有 node 节点上操作

上传 coredns.tar 到 /opt 目录中
cd /opt
docker load -i coredns.tar

1.2.在 master01 节点上操作

上传 coredns.yaml 文件到 /opt/k8s 目录中，部署 CoreDNS 
cd /opt/k8s
kubectl apply -f coredns.yaml

kubectl get pods -n kube-system

1.3.DNS 解析测试

kubectl run -it --rm dns-test --image=busybox:1.28.4 sh
If you don't see a command prompt, try pressing enter.
/ # nslookup kubernetes
Server:    10.0.0.2
Address 1: 10.0.0.2 kube-dns.kube-system.svc.cluster.local

Name:      kubernetes
Address 1: 10.0.0.1 kubernetes.default.svc.cluster.local

注：
如果出现以下报错
[root@master01 k8s]# kubectl run -it  --image=busybox:1.28.4 sh
If you don't see a command prompt, try pressing enter.
Error attaching, falling back to logs: unable to upgrade connection: Forbidden (user=system:anonymous, verb=create, resource=nodes, subresource=proxy)
Error from server (Forbidden): Forbidden (user=system:anonymous, verb=get, resource=nodes, subresource=proxy) ( pods/log sh)

需要添加 rbac的权限  直接使用kubectl绑定  clusteradmin 管理员集群角色  授权操作权限

[root@master01 k8s]# kubectl create clusterrolebinding cluster-system-anonymous --clusterrole=cluster-admin --user=system:anonymous
clusterrolebinding.rbac.authorization.k8s.io/cluster-system-anonymous created

二、master02 节点部署

2.1.从 master01 节点上拷贝证书文件、各master组件的配置文件和服务管理文件到 master02 节点

scp -r /opt/etcd/ root@192.168.190.104:/opt/
scp -r /opt/kubernetes/ root@192.168.190.104:/opt
scp -r /root/.kube root@192.168.190.104:/root
scp /usr/lib/systemd/system/{kube-apiserver,kube-controller-manager,kube-scheduler}.service root@192.168.190.104:/usr/lib/systemd/system/

2.2.修改配置文件kube-apiserver中的IP

vim /opt/kubernetes/cfg/kube-apiserver
KUBE_APISERVER_OPTS="--logtostderr=false  \
--v=2 \
--log-dir=/opt/kubernetes/logs \
--etcd-servers=https://192.168.190.101:2379,https://192.168.190.102:2379,https://192.168.190.103:2379 \
--bind-address=192.168.190.104 \                修改
--secure-port=6443 \
--advertise-address=192.168.190.104 \            修改
--allow-privileged=true \
--service-cluster-ip-range=10.0.0.0/24 \
..................

2.3.在 master02 节点上启动各服务并设置开机自启

systemctl start kube-apiserver.service
systemctl enable kube-apiserver.service
systemctl start kube-controller-manager.service
systemctl enable kube-controller-manager.service
systemctl start kube-scheduler.service
systemctl enable kube-scheduler.service

2.4./查看node节点状态

ln -s /opt/kubernetes/bin/* /usr/local/bin/
kubectl get nodes
kubectl get nodes -o wide			#-o=wide：输出额外信息；对于Pod，将输出Pod所在的Node名
//此时在master02节点查到的node节点状态仅是从etcd查询到的信息，而此时node节点实际上并未与master02节点建立通信连接，因此需要使用一个VIP把node节点与master节点都关联起来

三、负载均衡部署

配置load balancer集群双机热备负载均衡（nginx实现负载均衡，keepalived实现双机热备）

 在lb01、lb02节点上操作

3.1.配置nginx的官方在线yum源，配置本地nginx的yum源

cat > /etc/yum.repos.d/nginx.repo << 'EOF'
[nginx]
name=nginx repo
baseurl=http://nginx.org/packages/centos/7/$basearch/
gpgcheck=0
EOF

yum install nginx -y

3.2.修改nginx配置文件，配置四层反向代理负载均衡，指定k8s群集2台master的节点ip和6443端口

user  nginx;
worker_processes  auto;

error_log  /var/log/nginx/error.log notice;
pid        /var/run/nginx.pid;


events {
    worker_connections  1024;
}

stream {
    log_format  main  '$remote_addr $upstream_addr - [$time_local] $status $upstream_bytes_sent';
    
	access_log  /var/log/nginx/k8s-access.log  main;

    upstream k8s-apiserver {
        server 192.168.190.101:6443;
        server 192.168.190.104:6443;
    }
    server {
        listen 6443;
        proxy_pass k8s-apiserver;
    }
}



http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    keepalive_timeout  65;

    #gzip  on;

    include /etc/nginx/conf.d/*.conf;
}

3.3.检查配置文件语法

nginx -t   

//启动nginx服务，查看已监听6443端口
systemctl start nginx
systemctl enable nginx
netstat -natp | grep nginx 

3.4.部署keepalived服务

部署keepalived服务
yum install keepalived -y

//修改keepalived配置文件
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   # 接收邮件地址
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   # 邮件发送地址
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id NGINX_MASTER	#lb01节点的为 NGINX_MASTER，lb02节点的为 NGINX_BACKUP
}

#添加一个周期性执行的脚本
vrrp_script check_nginx {
    script "/etc/nginx/check_nginx.sh"	#指定检查nginx存活的脚本路径
}

vrrp_instance VI_1 {
    state MASTER			#lb01节点的为 MASTER，lb02节点的为 BACKUP
    interface ens33			#指定网卡名称 ens33
    virtual_router_id 51	#指定vrid，两个节点要一致
    priority 100			#lb01节点的为 100，lb02节点的为 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.190.100/24	#指定 VIP
    }
    track_script {
        check_nginx			#指定vrrp_script配置的脚本
    }
}

3.5.创建nginx状态检查脚本 

vim /etc/nginx/check_nginx.sh
#!/bin/bash
#egrep -cv "grep|$$" 用于过滤掉包含grep 或者 $$ 表示的当前Shell进程ID，即脚本运行的当前进程ID号
count=$(ps -ef | grep nginx | egrep -cv "grep|$$")

if [ "$count" -eq 0 ];then
    systemctl stop keepalived
fi


chmod +x /etc/nginx/check_nginx.sh

3.6.启动keepalived服务（一定要先启动了nginx服务，再启动keepalived服务）

systemctl start keepalived
systemctl enable keepalived
ip a				#查看VIP是否生成

3.7.修改node节点上的bootstrap.kubeconfig,kubelet.kubeconfig配置文件为VIP

cd /opt/kubernetes/cfg/
vim bootstrap.kubeconfig 
server: https://192.168.10.100:6443
                      
vim kubelet.kubeconfig
server: https://192.168.10.100:6443
                        
vim kube-proxy.kubeconfig
server: https://192.168.10.100:6443

//重启kubelet和kube-proxy服务
systemctl restart kubelet.service 
systemctl restart kube-proxy.service

3.8.在 lb01 上查看 nginx 和 node 、 master 节点的连接状态

netstat -natp | grep nginx
tcp        0      0 0.0.0.0:6443            0.0.0.0:*               LISTEN      84739/nginx: master 
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      84739/nginx: master 
tcp        0      0 192.168.190.105:60382     192.168.190.104:6443      ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.102:41650     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.103:49726     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.104:35234     192.168.190.101:6443      ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.102:41648     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.103:49728     ESTABLISHED 84742/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.102:41646     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.105:32786     192.168.190.104:6443      ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.102:41656     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.105:60378     192.168.190.104:6443      ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.105:32794     192.168.190.104:6443      ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.103:49724     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.105:35886     192.168.190.101:6443      ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.103:51372     ESTABLISHED 84742/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.103:49722     ESTABLISHED 84741/nginx: worker 
tcp        0      0 192.168.190.100:6443     192.168.190.103:49702     ESTABLISHED 84741/nginx: worker

3.9.在 master01 节点上操作

测试创建pod
kubectl run nginx --image=nginx

//查看Pod的状态信息
kubectl get pods
NAME                    READY   STATUS              RESTARTS   AGE
nginx-dbddb74b8-nf9sk   0/1     ContainerCreating   0          33s   #正在创建中

kubectl get pods
NAME                    READY   STATUS    RESTARTS   AGE
nginx-dbddb74b8-nf9sk   1/1     Running   0          80s  			#创建完成，运行中

kubectl get pods -o wide
NAME                    READY   STATUS    RESTARTS   AGE   IP            NODE            NOMINATED NODE
nginx-dbddb74b8-26r9l   1/1     Running   0          10m   172.17.36.2   192.168.80.15   <none>
//READY为1/1，表示这个Pod中有1个容器

//在对应网段的node节点上操作，可以直接使用浏览器或者curl命令访问
curl 172.17.36.2

//这时在master01节点上查看nginx日志
kubectl logs nginx-dbddb74b8-nf9sk