1、启停
1.1、注册成服务的启停方式
Haproxy重启
systemctl restart haproxy
Haproxy 启动
systemctl start haproxy
Haproxy 停止
systemctl restart haproxy
1.2、未注册成服务的启停方式
启动
haproxy -f /etc/haproxy/haproxy.cfg
停止
Ps –ef|grep haproxy 查出进程号
Kill -9 进程号
2、配置
HAProxy配置中分成五部分内容，当然这些组件不是必选的，可以根据需要选择部分作为配置。
global：
参数是进程级的，通常和操作系统（OS）相关。这些参数一般只设置一次，如果配置无误，就不需要再次配置进行修改
defaults：
配置默认参数的，这些参数可以被利用配置到frontend，backend，listen组件
frontend：
接收请求的前端虚拟节点，Frontend可以根据规则直接指定具体使用后端的 backend(可动态选择)。
backend：
后端服务集群的配置，是真实的服务器，一个Backend对应一个或者多个实体服务器。
listen：
Frontend和Backend的组合体。
-------------------------------------------------
BALANCE 选项：
balance source ：
如果想让HAProxy按照客户端的IP地址进行负载均衡策略，即同一IP地址的所有请求都发送到同一服务器时，需要配置此选项。
balance roundrobin ：
HAProxy把请求轮流的转发到每一个服务器上，依据每台服务器的权重，此权重会动态调整。最常见的默认配置。
一个配置示例
#---------------------------------------------------------------------
# Example configuration for a possible web application. See the
# full configuration options online.
#
# http://haproxy.1wt.eu/download/1.4/doc/configuration.txt
#
#---------------------------------------------------------------------
#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
# to have these messages end up in /var/log/haproxy.log you will
# need to:
#
# 1) configure syslog to accept network log events. This is done
# by adding the '-r' option to the SYSLOGD_OPTIONS in
# /etc/sysconfig/syslog
#
# 2) configure local2 events to go to the /var/log/haproxy.log
# file. A line like the following can be added to
# /etc/sysconfig/syslog
#
# local2.* /var/log/haproxy.log
#
log 127.0.0.1 local2
chroot /var/lib/haproxy
#将haproxy的进程号写入文件/var/run/haproxy.pid，启动haproxy进程的用户必须有对haproxy.pid文件的读写权限。
pidfile /var/run/haproxy.pid
#最大连接数
maxconn 4000
#用户
user haproxy
#组
group haproxy
#使haproxy进程进入后台运行，这是推荐的运行模式。
daemon
# turn on stats unix socket
stats socket /var/lib/haproxy/stats
#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
#默认的模式，可选项tcp和http
mode http
log global
option httplog
option dontlognull
option http-server-close
option forwardfor except 127.0.0.0/8
option redispatch
retries 3
timeout http-request 10s
timeout tunnel 3600s
timeout queue 1m
timeout connect 10s
timeout client 3m
timeout server 3m
timeout http-keep-alive 10s
timeout check 10s
maxconn 3000
#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend main
bind *:80
acl url_static path_beg -i /static /images /javascript /stylesheets
acl url_static path_end -i .jpg .gif .png .css .js
acl oss_url path_beg -i /cloud-web/oss/v1
# use_backend static if url_static
use_backend oss_backend if oss_url
default_backend cloudweb
#---------------------------------------------------------------------
# static backend for serving up images, stylesheets and such
#---------------------------------------------------------------------
backend static
balance roundrobin
server static 127.0.0.1:4331 check
#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend oss_backend
mode http
option httpchk HEAD / HTTP/1.0
reqrep ^([^\ ]*)\ /cloud-web/oss/v1/(.*) \1\ /v1/\2
server swift0 10.110.20.147:8081 check inter 2000 fall 3 weight 30
server swift1 10.110.20.148:8081 check inter 2000 fall 3 weight 30
backend cloudweb
mode http
option httpchk HEAD / HTTP/1.0
balance roundrobin
server app0 10.110.20.147:8080 check inter 2000 fall 3 weight 30
server app1 10.110.20.148:8080 check inter 2000 fall 3 weight 30
#listen rabbitmq *:5672
# mode tcp
# option tcpka
# balance roundrobin
# server mq1 10.110.19.240:5672 check inter 2000 fall 3
listen status
mode http
bind 0.0.0.0:50002
stats enable
stats hide-version
stats uri /state
stats auth admin:123456a?
stats admin if TRUE
一篇不错的文章
http://www.cnblogs.com/dkblog/archive/2012/03/13/2393321.html