Haproxy通过结合Keepalived实现负载均衡器节点的高可用

环境介绍：CentOS 6.5平台Haproxy1：10.10.10.128/24Haproxy2：10.10.10.129/24web1：10.10.10.130/24web2：10.10.10.131/24VIP：10.10.10.100/24

部署前准备：1、时间同步：ntpdate ntp1.aliyun.com2、防火墙策略：service iptables stopchkconfig iptables off3、SELinux策略：sed -i 's#SELINUX=enforcing#SELINUX=disabled#' /etc/selinux/config4、更换国内yum源：wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repoyum clean allyum makecache5、重启服务器rebootweb服务器配置：1、安装httpd服务    yum install httpd -y2、修改配置文件：/etc/httpd/conf/httpd.conf    .....    Listen 8080    ServerName 10.10.10.130:8080  #web1    ServerName 10.10.10.131:8080  #web23、修改web主页：/var/www/html/index.html    echo "web1" >/var/www/html/index.html     #web1    echo "web2" >/var/www/html/index.html     #web24、启动web服务：    service httpd start    chkconfig httpd on5、验证服务是否正常：    lsof -i:8080    curl 10.10.10.130:8080  #返回web1    curl 10.10.10.131:8080  #返回web2Haproxy服务器配置：1、安装Haproxy服务    yum install haproxy -y2、修改配置文件：/etc/haproxy/haproxy.cfg    cp /etc/haproxy/haproxy /etc/haproxy/haproxy.cfg.bak    vim /etc/haproxy/haproxy.cfg  .........  .........#---------------------------------------------------------------------# main frontend which proxys to the backends#---------------------------------------------------------------------frontend  main    bind 0.0.0.0:80    acl url_static       path_beg       -i /static /images /javascript /stylesheets    acl url_static       path_end       -i .jpg .gif .png .css .js    use_backend static          if url_static    default_backend             dynamic#---------------------------------------------------------------------# static backend for serving up images, stylesheets and such#---------------------------------------------------------------------backend static    balance     roundrobin    server      static 127.0.0.1:80 check#---------------------------------------------------------------------# round robin balancing between the various backends#---------------------------------------------------------------------backend dynamic    balance     roundrobin    server  web1 10.10.10.130:8080 check maxconn 2000    server  web2 10.10.10.131:8080 check maxconn 20003、检测配置文件是否正确：    haproxy -c -f /etc/haproxy/haproxy.cfg4、启动Haproxy    service haproxy start    chkconfig haproxy on5、验证是否正常解析：    curl 10.10.10.128  //重复两次，分别显示web1和web2    curl 10.10.10.129  //重复两次，分别显示web1和web2Keepalived配置：1、安装keepalived服务：    yum -y install keepalived2、修改配置文件：#MASTER端：! Configuration File for keepalived#定义检查脚本vrrp_script check_haproxy {        script "/etc/keepalived/check_haproxy.sh"        interval 2        weight 2}global_defs {   notification_email {        root@localhost   }   notification_email_from keepalived@localhost   smtp_server 127.0.0.1   smtp_connect_timeout 30   router_id haproxy1}vrrp_instance ha1 {    state MASTER    interface eth0    virtual_router_id 51    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        10.10.10.100/24 dev eth0    }    track_script{         check_haproxy    }}#BACKUP端：.........router_id haproxy2   #修改虚拟路由的IDstate BACKUP   #修改角色priority 80     #修改优先级重启各服务：service keepalived restartservice haproxy restart验证：ip addr发现虚拟ip：10.10.10.100在MASTER端访问10.10.10.100正常

/etc/keepalived/check_haproxy.sh#!/bin/bashA=`ps -C haproxy --no-header |wc -l`if [ $A -eq 0 ];then/etc/init.d/keepalived stopfi

验证Haproxy+Keepalived服务的可靠性：

web端：关闭web1的httpd服务，service httpd stopcurl 10.10.10.100  #正常返回web2Haproxy端：关闭haproxy1的keepalived服务，service keepalived stopcurl 10.10.10.100 #正常轮询返回web1/web2通过ip addr 可以查看 VIP漂移到Haproxy2中