环境准备：
| 主机名 | 角色 | IP地址 |
| mylinux1.contoso.com | haproxy服务器 | eth0:192.168.100.121 eth1:172.16.100.121 |
| mylinux3.contoso.com | web服务器1 | eth0:192.168.100.181 |
| mylinux4.contoso.com | web服务器2 | eth0:192.168.100.182 |
一、准备工作
在mylinux3和mylinux4上安装http服务，并启动。
yum -y install httpd/etc/init.d/httpd start
使用浏览器访问，保证服务正常。
二、修改haproxy配置文件
[root@mylinux1 conf]# cp haproxy.cfg haproxy.cfg.bak[root@mylinux1 conf]# vi haproxy.cfg[root@mylinux1 conf]# cat haproxy.cfg# this config needs haproxy-1.1.28 or haproxy-1.2.1global #log 127.0.0.1 local0 log 127.0.0.1:514 local0 warning pidfile /usr/local/haproxy/var/run/haproxy.pid daemon maxconn 4096 chroot /usr/local/haproxy/var/chroot user haproxy group haproxy nbproc 1 defaults log global mode http #默认的模式{tcp|http|health}，tcp是4层，http是7层，health只会返回OK retries 3 option httplog #日志类别，采用httplog option httpclose #每次请求完毕后主动关闭http通道,haproxy不支持keep-alive,只能模拟这种模式的实现 option dontlognull #不记录健康检查日志信息 option forwardfor #如果后端服务器需要获得客户端真实ip需要配置的参数，可以从Http Header中获得客户端ip option redispatch #当serverId对应的服务器挂掉后，强制定向到其他健康的服务器 maxconn 2000 balance roundrobin #设置默认负载均衡方式，轮询方式 timeout connect 5000 timeout client 50000 timeout server 50000 listen haproxy_stats bind *:8000 #绑定到本地所有IP地址的8000端口上 mode http #http的7层模式 option httplog #采用http日志格式 maxconn 20 #默认的最大连接数 stats enable #启用状态监控 stats refresh 30s #监控页面自动刷新时间 stats uri /haproxy_status #监控页面url stats auth admin:123456 #设置监控页面的用户名和密码，可以设置多个用户名 stats hide-version #隐藏监控页面上的Haproxy版本信息 listen websites bind 192.168.100.121:80 #绑定到192.168.100.121上的80端口 timeout server 15s timeout connect 30s server mylinux3 192.168.100.181:80 check port 80 inter 2000 fall 3 #检测健康端口80，检测心跳频率是2000ms，失败3次则认为服务器不可用 server mylinux4 192.168.100.182:80 check port 80 inter 2000 fall 3 三、启动haproxy并测试
1、启动haproxy
[root@mylinux1 conf]# /usr/local/haproxy/sbin/haproxy -f haproxy.cfg -cConfiguration file is valid[root@mylinux1 conf]# /usr/local/haproxy/sbin/haproxy -f haproxy.cfg -D[root@mylinux1 conf]# ps -ef|grep haproxyhaproxy 2575 1 0 23:24 ? 00:00:00 /usr/local/haproxy/sbin/haproxy -f /usr/local/haproxy/conf/haproxy.cfgroot 2584 1015 0 23:45 pts/1 00:00:00 grep haproxy
2、测试haproxy监控页面
3、web访问测试
4、后端节点负载测试
首先使用curl测试一下获取网页内容：
[root@mylinux1 conf]# curl -s http://192.168.100.121
<html>
<head>
<title>Web1</title>
</head>
<body>
<p align="center">
<span style="color:blue;font-size:24px">Web Site 1</span>
</p>
<hr />
<h1 align="center">mylinux3.contoso.com</h1>
</body>
</html>
[root@mylinux1 conf]# curl -s http://192.168.100.121
<html>
<head>
<title>Web2</title>
</head>
<body>
<p align="center">
<span style="color:blue;font-size:24px">Web Site 2</span>
</p>
<hr />
<h1 align="center">mylinux4.contoso.com</h1>
</body>
</html>
然后使用for循环测试100次，并将100次的结果全部追加到一个文件中去，最后检查每个节点出现的次数：
[root@mylinux1 conf]# for i in {1..100};do curl http://192.168.100.121/ >>/tmp/webtest.txt;done[root@mylinux1 conf]# grep mylinux3.contoso.com /tmp/webtest.txt |wc -l50[root@mylinux1 conf]# grep mylinux4.contoso.com /tmp/webtest.txt |wc -l50 结果是mylinux3和mylinux4都访问了50次，证明轮询方式下负载是一样的。
四、haproxy启动停止脚本
#!/bin/bash#####################################################chkconfig: 2345 20 70#description: Start and stop haproxy service.#Author: Jerry Zhao QQ:1217406852#Date: 2016-09-30 19:46:42 Friday###################################################BASE=/usr/local/haproxyPROG=$BASE/sbin/haproxyPIDFILE=$BASE/var/run/haproxy.pidCONFFILE=$BASE/conf/haproxy.cfgRUNNING_STATUS=`ps -ef|grep "haproxy -f"|egrep -v grep|wc -l`start(){ RUNNING_STATUS=`ps -ef|grep "haproxy -f"|egrep -v grep|wc -l` if [ $RUNNING_STATUS -ge 1 ];then echo "Haproxy is already running! Exit now." exit 1 else $PROG -f $CONFFILE [ $? -eq 0 ] && echo "Start haproxy successful." || echo "Start haproxy failed." fi}stop(){ if [ $RUNNING_STATUS -lt 1 ];then echo "Haproxy is not running. Stop haproxy failed!" else kill -9 $(cat $PIDFILE) [ $? -eq 0 ] && echo "Stop haproxy successful." || echo "Stop haproxy failed." rm -rf $PIDFILE fi}reload(){ if [ ! -f $PIDFILE ];then echo "No pid file found. Maybe you need to check haproxy status first." exit 1 else $PROG -f $CONFFILE -sf $(cat $PIDFILE) fi }status(){ if [ $RUNNING_STATUS -ge 1 ];then PID_NUM=`cat $PIDFILE` echo "Haproxy (pid $PID_NUM) is running..." else echo "Haproxy is stopped." fi}check(){ $PROG -f $CONFFILE -c}case $1 in start) start ;; stop) stop ;; restart) stop start ;; reload) reload ;; status) status ;; check) check ;; *) echo "USAGE: $0 start|stop|restart|reload|check ." exit 1 ;;esac 测试一下：
[root@mylinux1 ~]# cp haproxy /etc/init.d/[root@mylinux1 ~]# ll /etc/init.d/haproxy -rwxr-xr-x 1 root root 1567 Oct 1 00:06 /etc/init.d/haproxy[root@mylinux1 ~]# service haproxy statusHaproxy (pid 2575) is running...[root@mylinux1 ~]# service haproxy stopStop haproxy successful.[root@mylinux1 ~]# service haproxy startStart haproxy successful.[root@mylinux1 ~]# service haproxy restartStop haproxy successful.Start haproxy successful.[root@mylinux1 ~]# service haproxy statusHaproxy (pid 2796) is running...[root@mylinux1 ~]# service haproxy reload[root@mylinux1 ~]# service haproxy statusHaproxy (pid 2822) is running...[root@mylinux1 ~]# service haproxy checkConfiguration file is valid