keepalived+lvs-dr实现高可用负载均衡

实验拓扑

实验要求

1. RS1与RS2地址为172.18.27.201/202
2. VS1和VS2地址为172.18.27.103/200，VIP为172.18.27.254
3. VS1和VS2实现lvs-dr负载均衡及高可用性，且vs为sorry sever。
4. keepalived是单主模式。

   实验步骤
   

5. 各个主机安装必备软件

   ##RS1与RS2安装httpd
   yum install -y httpd
   ##VS1与VS2安装keeplived和httpd
   yum instll keepalived httpd -y 
   ##所有主机同步时间
   ntpdate 2.cn.pool.ntp.org

6. 配置RS1与RS2

   RS1配置，RS1的系统为centos7.2.
   ##配置测试页
   vim /var/www/html/index.html
   <h1/>R1:172.18.27.201</h1>
   ##启动httpd服务
   systemctl restart httpd.service
   ##配置VIP，并关闭内核中的arp_ignore,建议写脚本
   [root@localhost bin]#vi setparam.sh           
   #！/bin/bash
   vip="172.18.27.254"
   start (){
        ifconfig lo:0 $vip netmask 255.255.255.255 broadcast $vip up
        echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
        echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce
        echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
        echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore
        route add -host $vip dev lo:0
   }
   stop (){
        echo 0 > /proc/sys/net/ipv4/conf/all/arp_announce
        echo 0 > /proc/sys/net/ipv4/conf/lo/arp_announce
        echo 0 > /proc/sys/net/ipv4/conf/all/arp_ignore
        echo 0 > /proc/sys/net/ipv4/conf/lo/arp_ignore
        ifconfig lo:0 down
   }
   case $1 in
   start)
        start
        echo "arp_announce set ok"
        echo "arp_ignore set ok"
        echo "lo:0 up"
        ;;
   stop)
        stop
        echo "arp_announce set ok"
        echo "arp_ignore set ok"
        echo "lo:0 down"
        ;;
   *)
        echo "$0 stop|start"
        ;;
   esac

   RS2配置，RS1的系统为centos7.2。
   ##配置测试页
   vim /var/www/html/index.html
   <h1/>R2:172.18.27.202</h1>
   ##启动httpd服务
   systemctl restart httpd.service
   ##用RS1的脚本配置RS2

7. 配置VS1和VS2

   ##VS1配置,VS1系统是centos6.8。
   #配置sorry_server
   yum install -y httpd
   vim /var/www/html/index.html
   <h1/>sorry server 1:172.18.27.102</h1>
   启动服务
   srvice httpd start
   #配置keepalived
   vim /etc/keepalived/keepalived.conf
   ! Configuration File for keepalived 
   global_defs { 
        notification_email {                            ##报警邮箱设置
                root@localhost                            ##报警邮箱
        }
        notification_email_from keepalived@localhost    ##报警有哪个用户发送
        smtp_server 127.0.0.1                            ##报警邮箱服务器
        smtp_connect_timeout 30                            ##报警超时时间
        vrrp_mcast_group4 224.100.27.1                    ##通过组播地址，通告状态和优先级等信息
   }
   vrrp_instance VI_1 {                                    ##设置vrrp
    state MASTER                                        ##设置主从
    interface eth1                                        ##vrrp实例工作的网络接口
    virtual_router_id 51                                ##设置vrrp的id标识符，0-255
    priority 100                                        ##设定优先级
    advert_int 1                                        ##对外的通知时间间隔
    authentication {                                    ##设定认证方式
        auth_type PASS
        auth_pass 1111
    }
    track_interface {                                    ##设定监听网络接口
        eth1
    }   
    nopreempt                                            ##设定是否为抢占和非抢占模式
    virtual_ipaddress {                                    ##定义VIP
        172.18.27.254/16 dev eth1 label eth1:0            ##设定VIP在那个网络接口上
    }  
   }   
   virtual_server 172.18.27.254 80 {                        
        delay_loop 6                                    ##定义服务轮询间隔，多久检查RS的健康状态
        lb_algo wrr                                        ##设定VS的调用方法
        lb_kind DR                                        ##设定lvs的调用类型
        protocol TCP                                    ##设定工作的协议
        sorry_server 127.0.0.1 80                        ##设定sorry_server
        real_server 172.18.27.201 80 {                    ##设定RS
                weight 1                                ##设定权重
                HTTP_GET {                                ##设定RS健康状态查询方法
                        url {                            根据urlde状态码来确定RS的状态
                                path /
                                status_code 200
                        }
                connect_timeout 1                        ##设定检查的超时时长
                nb_get_retry 3                            ##设定检查的重试次数
                delay_before_retry 1                    ##设定检查延迟时间
   
                }
        }
        real_server 172.18.27.202 80 {
                weight 2
                HTTP_GET {
                        url {
                                path /  
                                status_code 200
                        }
                connect_timeout 1
                nb_get_retry 3
                delay_before_retry 1    
   
                }
        }
   } 
   #启动服务
   service keepalived start

   ##配置VS2，VS2的系统是centOS7.2.
   #配置sorry_server
   yum install -y httpd
   vim /var/www/html/index.html
   <h1/>sorry server 2:172.18.27.200</h1>
   启动服务
   systemctl start httpd
   #配置keepalived
   ! Configuration File for keepalived
   global_defs { 
        notification_email {
                root@localhost
        }
        notification_email_from keepalived@localhost
        smtp_server 127.0.0.1
        smtp_connect_timeout 30
        vrrp_mcast_group4 224.100.27.1
   }
   vrrp_instance VI_1 {
    state BACKUP
    interface eno16777736
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_interface {
        eno16777736
    }   
    nopreempt
    virtual_ipaddress {
        172.18.27.254/16 dev eno16777736 label eno16777736:0
    }
   }   
   virtual_server 172.18.27.254 80 {
        delay_loop 6
        lb_algo wrr
        lb_kind DR
        net_mask 255.255.0.0
        protocol TCP
        sorry_server 127.0.0.1 80
        real_server 172.18.27.201 80 {
                weight 1
                HTTP_GET {
                        url {
                                path /
                                status_code 200
                        }
                connect_timeout 1
                nb_get_retry 3
                delay_before_retry 1
                }
        }
        real_server 172.18.27.202 80 {
                weight 2
                HTTP_GET {
                        url {
                                path /  
                                status_code 200
                        }
                connect_timeout 1
                nb_get_retry 3
                delay_before_retry 1                 
                }
        }
   } 
   #启动服务
   systemctl start keeplived

   测试实验效果
   

   在client测试实验效果
   for i in {1..10};do curl 172.18.27.254 ;done

   正常状态的测试效果
   

   

   一台RS挂掉之后
   

   

   两台RS都挂掉