编译安装haproxy：
1.下载haproxy的源码包
# wget http://www.haproxy.org/download/1.5/src/haproxy-1.5.14.tar.gz
2.编译安装
# tar xf haproxy-1.5.14.tar.gz
# cd haproxy-1.5.14
# uname -a ###查看linux内核版本
# make TARGET=linux26 PREFIX=/usr/local/haproxy
# make install PREFIX=/usr/local/haproxy
3.提供配置文件（编译安装默认是没有配置文件的）
# mkdir /etc/haproxy
# cd /etc/haproxy
# vim haproxy.cfg
#---------------------------------------------------------------------
# Example configuration for a possible web application. See the
# full configuration options online.
#
# http://haproxy.1wt.eu/download/1.3/doc/configuration.txt
#
#---------------------------------------------------------------------
#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
log 127.0.0.1 local2 ###[err warning info debug]
chroot /usr/local/haproxy
pidfile /var/run/haproxy.pid ###haproxy的pid存放路径,启动进程的用户必须有权限访问此文件
maxconn 4000 ###最大连接数，默认4000
user haproxy
group haproxy
daemon ###创建1个进程进入deamon模式运行。此参数要求将运行模式设置为"daemon"
#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
mode http ###默认的模式mode { tcp|http|health }，tcp是4层，http是7层，health只会返回OK
log global ###采用全局定义的日志
option dontlognull ###不记录健康检查的日志信息
option httpclose ###每次请求完毕后主动关闭http通道
option httplog ###日志类别http日志格式
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 ###serverId对应的服务器挂掉后,强制定向到其他健康的服务器
timeout connect 10000 #default 10 second timeout if a backend is not found
timeout client 300000 ###客户端连接超时
timeout server 300000 ###服务器连接超时
maxconn 60000 ###最大连接数
retries 3 ###3次连接失败就认为服务不可用，也可以通过后面设置
#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend main *:5000
acl url_static path_beg -i /static /p_w_picpaths /javascript /stylesheets
acl url_static path_end -i .jpg .gif .png .css .js
use_backend static if url_static ###满足策略要求，则响应策略定义的backend页面
default_backend app ###不满足则响应backend的默认页面
#---------------------------------------------------------------------
# static backend for serving up p_w_picpaths, stylesheets and such
#---------------------------------------------------------------------
backend static
balance roundrobin ###负载均衡模式轮询
server static 127.0.0.1:4331 check ###后端服务器定义
#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend app
balance roundrobin ###负载均衡模式轮询
server app1 127.0.0.1:5001 check ###后端服务器定义，check进行健康检查
server app2 127.0.0.1:5002 check
server app3 127.0.0.1:5003 check
server app4 127.0.0.1:5004 check
5.新建haproxy用户以安全方式运行进程
# groupadd -r -g 158 haproxy
# useradd -g haproxy -r -s /sbin/nologin -u 102 haproxy
6.配置haproxy服务的日志
# vim /etc/rsysconfig/rsyslog
SYSLOGD_OPTIONS="-c 2 -r"
# vim /etc/rsyslog.conf
local2.* /var/log/haproxy.log ###在文件的最后添加一行
# service rsyslog restart ###重启系统日志服务使其生效
7.检查配置文件是否错误
# /usr/local/haproxy/sbin/haproxy -c -f /etc/haproxy/haproxy.cfg
8.启动haproxy服务
# /usr/local/haproxy/sbin/haproxy -f /etc/haproxy/haproxy.cfg
# netstat -tnulp | grep haproxy or ps -ef | grep haproxy
9.关闭haproxy服务
# killall haproxy
10.提供haproxy服务启动脚本
# vim /etc/rc.d/init.d/haproxy
#!/bin/bash
#
# haproxy
#
# chkconfig: 35 85 15
# description: HAProxy is a free, very fast and reliable solution \
# offering high availability, load balancing, and \
# proxying for TCP and HTTP-based applications
# processname: haproxy
# config: /etc/haproxy/haproxy.cfg
# pidfile: /var/run/haproxy.pid
# Source function library.
. /etc/rc.d/init.d/functions
# Source networking configuration.
. /etc/sysconfig/network
# Check that networking is up.
[ "$NETWORKING" = "no" ] && exit 0
config="/etc/haproxy/haproxy.cfg"
exec="/usr/local/haproxy/sbin/haproxy"
prog=$(basename $exec)
[ -e /etc/sysconfig/$prog ] && . /etc/sysconfig/$prog
lockfile=/var/lock/subsys/haproxy
check() {
$exec -c -V -f $config
}
start() {
$exec -c -q -f $config
if [ $? -ne 0 ]; then
echo "Errors in configuration file, check with $prog check."
return 1
fi
echo -n $"Starting $prog: "
# start it up here, usually something like "daemon $exec"
daemon $exec -D -f $config -p /var/run/$prog.pid
retval=$?
echo
[ $retval -eq 0 ] && touch $lockfile
return $retval
}
stop() {
echo -n $"Stopping $prog: "
# stop it here, often "killproc $prog"
killproc $prog
retval=$?
echo
[ $retval -eq 0 ] && rm -f $lockfile
return $retval
}
restart() {
$exec -c -q -f $config
if [ $? -ne 0 ]; then
echo "Errors in configuration file, check with $prog check."
return 1
fi
stop
start
}
reload() {
$exec -c -q -f $config
if [ $? -ne 0 ]; then
echo "Errors in configuration file, check with $prog check."
return 1
fi
echo -n $"Reloading $prog: "
$exec -D -f $config -p /var/run/$prog.pid -sf $(cat /var/run/$prog.pid)
retval=$?
echo
return $retval
}
force_reload() {
restart
}
fdr_status() {
status $prog
}
case "$1" in
start|stop|restart|reload)
$1
;;
force-reload)
force_reload
;;
checkconfig)
check
;;
status)
fdr_status
;;
condrestart|try-restart)
[ ! -f $lockfile ] || restart
;;
*)
echo $"Usage: $0 {start|stop|status|checkconfig|restart|try-restart|reload|force-reload}"
exit 2
esac
11.而后为此脚本赋予执行权限
# chmod +x /etc/rc.d/init.d/haproxy
12.添加至服务管理列表，并让其开机自动启动
# chkconfig --add haproxy
# chkconfig haproxy on
# service haproxy start
13.查看服务是否正常启动
# ps -ef | grep haproxy
14.输出haproxy的man手册至man命令的查找路径
# vim /etc/man.config，添加如下行即可
MANPATH /usr/local/haproxy/share/man
15.修改PATH环境变量，让系统可以直接使用haproxy的相关命令
# vim /etc/profile.d/haproxy.sh
export PATH=$PATH:/usr/local/haproxy/sbin
16.重新读取环境变量的值
# source /etc/profile
