keepalived 负载均衡实例

目的：利用keepalived 实现http的负载均衡  用户访问192.168.1.153，实现对sr1和sr2的负载均衡。

实验环境：

        sr1: 192.168.1.151  http服务

        sr2: 192.168.1.152  http服务

        ka1: 192.168.1.150 主keepalived

        ka2: 192.168.1.149 备keepalived

        vip: 192.168.1.153  虚拟IP

操作步骤：

        一：sr1、sr2 安装 httpd 服务、配置虚拟IP

            yum -y install httpd

            mkdir /etc/sh

            vim /etc/sh/dr.sh

                #!/bin/bash
                vip=192.168.1.153
                ifconfig lo:0 $vip broadcast $vip netmask 255.255.255.255 up
                route add -host $vip lo:0
                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

            更改权限并运行

                 chmod 700 /etc/sh/dr.sh;bash /etc/sh/dr.sh

             ifconfig 查看lo:0处于up状态。

        

        二：ka1、ka2安装keepalived、ipvsadm服务

            yum -y install keepalived

            yum -y install ipvsadm

        

        三：配置主keepalived

            vim /etc/keepalived/keeplived.conf

                ! Configuration File for keepalived

global_defs {                     #全局配置
   notification_email {
     [email protected]       #如有故障时，收件的email邮箱，可不填
     [email protected]
   }
   notification_email_from [email protected]
   smtp_server 192.168.1.202
   smtp_connect_timeout 30     #邮件服务器连接超时的最长时间
   router_id LVS_DEVEL
}

vrrp_instance VI_1 {
    state MASTER            #主keepalived 为 MASTER,备keepalived设为BACKUP
    interface eth0
    virtual_router_id 51
    priority 100          #主keepalived的的优先级，备keepalived的可设为90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }

 virtual_ipaddress {
        192.168.1.153    #虚拟IP
    }
}

virtual_server 192.168.1.153 80 {
    delay_loop 6    #每6秒检查一次服务是否正常
    lb_algo rr      #负载均衡的调度算法方式，一般使用rr或者wlc

    lb_kind DR      #负载均衡的模式，TUN、NTA、DR三种
    nat_mask 255.255.255.0
    persistence_timeout 2  #会话保持时间，单位：秒。如果是动态服务，建议开启。

    protocol TCP           #通讯模式。TCP UDP

    real_server 192.168.1.151 80 {   #真实服务的IP
        weight 100                   #权重值，数值越大，权重越高，分发的可能越大                TCP_CHECK {
        connect_timeout 10       #(10秒无响应超时)
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80          #端口
        }
    }

 real_server 192.168.1.152 80 { 
        weight 10
        TCP_CHECK {
        connect_timeout 10       #(10秒无响应超时)
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
}

        四：配置备keepalived

            vim /etc/keepalived/keepalived.conf

            在主keepalived.conf 基础上把

            1：state MASTER 修改为 state BACKUP

            2：priority 100 修改为 priority 90

        五：先启动ka1,再启动ka2

            ka1 : /etc/init.d/keepalived start;

            ka2 : /etc/init.d/keepalived start;

        六：浏览器访问http://192.168.1.153 进行测试。