lvs+keepalived（DR）

DR工作模式参考：http://os.51cto.com/art/201105/264303.htm

LVS详细参考：      http://www.it165.net/admin/html/201401/2248.html

 

一、搭建环境

      master:192.168.181.129 （director）

      backup:192.168.181.133

      realserver:192.168.181.131

      realserver:192.168.181.132

      vip： 192.168.181.134

      系统均为CentOS 6.6

二、安装：

      yum install -y ipvsadm

      yum install -y keepalived

     

Director 上 vim /usr/local/sbin/lvs_dr.sh   //增加

#! /bin/bash
echo 1 > /proc/sys/net/ipv4/ip_forward
ipv=/sbin/ipvsadm
vip=192.168.181.134
rs1=192.168.181.131
rs2=192.168.181.132
ifconfig eth0:0 $vip broadcast $vip netmask 255.255.255.255 up
route add -host $vip dev eth0:0
$ipv -C
$ipv -A -t $vip:80 -s rr
$ipv -a -t $vip:80 -r $rs1:80 -g -w 1
$ipv -a -t $vip:80 -r $rs2:80 -g -w 1

两台realserver上：vim /usr/local/sbin/lvs_dr_rs.sh  //增加

#! /bin/bash
vip=192.168.181.134
ifconfig lo:0 $vip broadcast $vip netmask 255.255.255.255 up
route add -host $vip lo:0

#避免arp广播问题

echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore

echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce

 

编写配置文件：

vim /etc/keepalived/keepalived.conf 

! Configuration File for keepalived
#邮件部分不需要的话可注释
global_defs {
   notification_email {
    [email protected]                                   # 发生故障时发送的邮箱
   }
   notification_email_from [email protected]             # 使用哪个邮箱发送
   smtp_server linuxzen.com                                  # 发件服务器
   smtp_connect_timeout 30
   router_id LVS_DEVEL
}
vrrp_instance VI_1 {
    state MASTER                                             #备用服务器上为 BACKUP
    interface eth0                                           # HA检测端口
    virtual_router_id 51                                     # 主备的virtual_router_id 必须相同
    priority 100                                             # 优先级,备lvs要比主lvs稍小，备用服务器上为90
    advert_int 1                                             # VRRP Multicast 广播周期秒数
    authentication {                                         # 定义认证
        auth_type PASS                                       # 认证方式为口令认证
        auth_pass 1111                                       # 定义口令
    }
    virtual_ipaddress {                                      #定义vip
        192.168.181.134                                      # 多个vip可换行添加
    }
}

virtual_server 192.168.181.134 80 {
    delay_loop 6                                             # 每隔6秒查看realserver状态
    lb_algo wlc                                              # 调度算法为加权最小连接数（lvs算法）
    lb_kind DR                                               # lvs工作模式为DR(直接路由)模式
    persistence_timeout 50                                   # 同一IP 的连接50秒内被分配到同一台realserver
    protocol TCP                                             # 用TCP监测realserver的状态

    real_server 192.168.181.131 80 {
        weight 100                                             #权重
        TCP_CHECK {
        connect_timeout 10                                   #（10s无响应超时）
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
    real_server 192.168.181.132 80 {
        weight 100
        TCP_CHECK {
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
   real_server 192.168.181.129 80 {
        weight 100
        TCP_CHECK {
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
}
}

以上为主director的配置文件，从director的配置文件只需要修改
state MASTER  -> state BACKUP
priority 100 -> priority 90
配置完keepalived后，需要开启端口转发（主从都要做）：
echo 1 > /proc/sys/net/ipv4/ip_forward
然后，两个rs上执行 /usr/local/sbin/lvs_dr_rs.sh 脚本
最后，两个director上启动keepalived服务（先主后从）：

/etc/init.d/keepalived start

 

可将master或者backup上的keepalived服务停掉做模拟故障，日志在/var/log/message上显示