基于Keepalived+Haproxy搭建四层负载均衡器

一、前言
       Haproxy是稳定、高性能、高可用性的负载均衡解决方案，支持HTTP及TCP代理后端服务器池，因支持强大灵活的7层acl规则，广泛作为HTTP反向代理。本文则详细介绍如何利用它的四层交换与Keepalived实现一个负载均衡器，适用于Socket、ICE、Mail、Mysql、私有通讯等任意TCP服务。系统架构图如下：



二、平台环境

OS:Centos5.4(64X)
MASTER:192.168.0.20
BACKUP:192.168.0.21
VIP:192.168.0.100
Serivce Port:11231
 

三、平台安装配置
1、添加非本机IP邦定支持

#vi /etc/sysctl.conf
net.ipv4.ip_nonlocal_bind=1
#sysctl –p
 

2、配置平台日志支持

#vi /etc/syslog.conf
添加：
local3.*        /var/log/haproxy.log
local0.*        /var/log/haproxy.log

#vi /etc/sysconfig/syslog
修改：
SYSLOGD_OPTIONS="-r -m 0"
#/etc/init.d/syslog restart
 

3、关闭SELINUX

vi /etc/sysconfig/selinux
修改：
SELINUX=disabled
#setenforce 0
 

4、配置iptables，添加VRRP通讯支持

iptables -A INPUT -d 224.0.0.18 -j ACCEPT
 

5、Keepalived的安装、配置

#mkdir -p /home/install/keepalivedha
#cd /home/install/keepalivedha
#wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz
#tar zxvf keepalived-1.2.2.tar.gz
#cd keepalived-1.2.2
#./configure
#make && make install
 

#cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
#cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
#mkdir /etc/keepalived
#cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/
#cp /usr/local/sbin/keepalived /usr/sbin/
 

#vi /etc/keepalived/keepalived.conf

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! Configuration File for keepalived

global_defs {
   notification_email {
         [email protected]
   }
   notification_email_from [email protected]
   smtp_connect_timeout 3
   smtp_server 127.0.0.1
   router_id LVS_DEVEL
}
vrrp_script chk_haproxy {
    script "killall -0 haproxy"
    interval 2
    weight 2
}
vrrp_instance VI_1 {
    interface eth1
    state MASTER # 从为BACKUP
    priority 101 # 从为100
    virtual_router_id 50 #路由ID，可通过#tcpdump vrrp查看。
    garp_master_delay 1 #主从切换时间，单位为秒。

    authentication {
        auth_type PASS
        auth_pass KJj23576hYgu23IP
    }
    track_interface {
       eth0
       eth1
    }
    virtual_ipaddress {
        192.168.0.100
    }
    track_script {
        chk_haproxy
    }

    #状态通知
    notify_master "/etc/keepalived/Mailnotify.py master"
    notify_backup "/etc/keepalived/Mailnotify.py backup"
    notify_fault "/etc/keepalived/Mailnotify.py fault"
}

! Configuration File for keepalived global_defs {    notification_email {          [email protected]    }    notification_email_from [email protected]    smtp_connect_timeout 3    smtp_server 127.0.0.1    router_id LVS_DEVEL } vrrp_script chk_haproxy {     script "killall -0 haproxy"     interval 2     weight 2 } vrrp_instance VI_1 {     interface eth1     state MASTER # 从为BACKUP     priority 101 # 从为100     virtual_router_id 50 #路由ID，可通过#tcpdump vrrp查看。     garp_master_delay 1 #主从切换时间，单位为秒。     authentication {         auth_type PASS         auth_pass KJj23576hYgu23IP     }     track_interface {        eth0        eth1     }     virtual_ipaddress {         192.168.0.100     }     track_script {         chk_haproxy     }     #状态通知     notify_master "/etc/keepalived/Mailnotify.py master"     notify_backup "/etc/keepalived/Mailnotify.py backup"     notify_fault "/etc/keepalived/Mailnotify.py fault" }
6、Haproxy的安装与配置

#cd /home/install/keepalivedha
#wget http://haproxy.1wt.eu/download/1.4/src/haproxy-1.4.11.tar.gz
#tar -zxvf haproxy-1.4.11.tar.gz
#cd haproxy-1.4.11
#make install
#mkdir -p /usr/local/haproxy/etc
#mkdir -p /usr/local/haproxy/sbin
#cp examples/haproxy.cfg /usr/local/haproxy/etc
#ln -s /usr/local/sbin/haproxy /usr/local/haproxy/sbin/haproxy
 

#vi /usr/local/haproxy/etc/haproxy.cfg

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# this config needs haproxy-1.1.28 or haproxy-1.2.1

global
#        log 127.0.0.1   local0
        log 127.0.0.1   local1 notice
        maxconn 5000
        uid 99
        gid 99
        daemon
        pidfile /usr/local/haproxy/haproxy.pid


defaults
        log     global
        mode    http
        #option httplog
        option  dontlognull
        retries 3
        option redispatch
        maxconn 2000
        contimeout      5000
        clitimeout      50000
        srvtimeout      50000

listen  ICE01   192.168.0.100:11231
        mode tcp #配置TCP模式
        maxconn 2000
        balance roundrobin
        server  ice-192.168.0.128 192.168.0.128:11231 check inter 5000 fall 1 rise 2
        server  ice-192.168.0.129 192.168.0.129:11231 check inter 5000 fall 1 rise 2
        server  ice-192.168.0.130 192.168.0.130:11231 check inter 5000 fall 1 rise 2
        server  ice-192.168.0.131 192.168.0.131:11231 check inter 5000 fall 1 rise 2
        server  ice-192.168.0.132 192.168.0.132:11231 check inter 5000 fall 1 rise 2
        server  ice-192.168.0.34 192.168.0.34:11231 check inter 5000 fall 1 rise 2
        srvtimeout      20000

listen stats_auth 192.168.0.20:80
# listen stats_auth 192.168.0.21:80 # backup config
        stats enable
        stats uri  /admin-status #管理地址
        stats auth  admin:123456 #管理帐号:管理密码
        stats admin if TRUE

# this config needs haproxy-1.1.28 or haproxy-1.2.1 global #        log 127.0.0.1   local0         log 127.0.0.1   local1 notice         maxconn 5000         uid 99         gid 99         daemon         pidfile /usr/local/haproxy/haproxy.pid defaults         log     global         mode    http         #option httplog         option  dontlognull         retries 3         option redispatch         maxconn 2000         contimeout      5000         clitimeout      50000         srvtimeout      50000 listen  ICE01   192.168.0.100:11231         mode tcp #配置TCP模式         maxconn 2000         balance roundrobin         server  ice-192.168.0.128 192.168.0.128:11231 check inter 5000 fall 1 rise 2         server  ice-192.168.0.129 192.168.0.129:11231 check inter 5000 fall 1 rise 2         server  ice-192.168.0.130 192.168.0.130:11231 check inter 5000 fall 1 rise 2         server  ice-192.168.0.131 192.168.0.131:11231 check inter 5000 fall 1 rise 2         server  ice-192.168.0.132 192.168.0.132:11231 check inter 5000 fall 1 rise 2         server  ice-192.168.0.34 192.168.0.34:11231 check inter 5000 fall 1 rise 2         srvtimeout      20000 listen stats_auth 192.168.0.20:80 # listen stats_auth 192.168.0.21:80 # backup config         stats enable         stats uri  /admin-status #管理地址         stats auth  admin:123456 #管理帐号:管理密码         stats admin if TRUE
7、邮件通知程序(python实现)
#vi /etc/keepalived/Mailnotify.py

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#!/usr/local/bin/python
#coding: utf-8
from email.MIMEMultipart import MIMEMultipart
from email.MIMEText import MIMEText
from email.MIMEImage import MIMEImage
from email.header import Header
import sys
import smtplib

#---------------------------------------------------------------
# Name:        Mailnotify.py
# Purpose:     Mail notify to SA
# Author:      Liutiansi
# Email:       [email protected]
# Created:     2011/03/09
# Copyright:   (c) 2011
#--------------------------------------------------------------
strFrom = '[email protected]'
strTo = '[email protected]'
smtp_server='smtp.domain.com'
smtp_pass='123456'

if sys.argv[1]!="master" and sys.argv[1]!="backup"  and sys.argv[1]!="fault":
    sys.exit()
else:
    notify_type=sys.argv[1]


mail_title='[紧急]负载均衡器邮件通知'
mail_body_plain=notify_type+'被激活，请做好应急处理。'
mail_body_html='<b><font color=red>'+notify_type+'被激活，请做好应急处理。</font></b>'

msgRoot = MIMEMultipart('related')
msgRoot['Subject'] =Header(mail_title,'utf-8')
msgRoot['From'] = strFrom
msgRoot['To'] = strTo

msgAlternative = MIMEMultipart('alternative')
msgRoot.attach(msgAlternative)

msgText = MIMEText(mail_body_plain, 'plain', 'utf-8')
msgAlternative.attach(msgText)


msgText = MIMEText(mail_body_html, 'html','utf-8')
msgAlternative.attach(msgText)


smtp = smtplib.SMTP()
smtp.connect(smtp_server)
smtp.login(smtp_user,smtp_pass)
smtp.sendmail(strFrom, strTo, msgRoot.as_string())
smtp.quit()

#!/usr/local/bin/python #coding: utf-8 from email.MIMEMultipart import MIMEMultipart from email.MIMEText import MIMEText from email.MIMEImage import MIMEImage from email.header import Header import sys import smtplib #--------------------------------------------------------------- # Name:        Mailnotify.py # Purpose:     Mail notify to SA # Author:      Liutiansi # Email:       [email protected] # Created:     2011/03/09 # Copyright:   (c) 2011 #-------------------------------------------------------------- strFrom = '[email protected]' strTo = '[email protected]' smtp_server='smtp.domain.com' smtp_pass='123456' if sys.argv[1]!="master" and sys.argv[1]!="backup"  and sys.argv[1]!="fault":     sys.exit() else:     notify_type=sys.argv[1] mail_title='[紧急]负载均衡器邮件通知' mail_body_plain=notify_type+'被激活，请做好应急处理。' mail_body_html='<b><font color=red>'+notify_type+'被激活，请做好应急处理。</font></b>' msgRoot = MIMEMultipart('related') msgRoot['Subject'] =Header(mail_title,'utf-8') msgRoot['From'] = strFrom msgRoot['To'] = strTo msgAlternative = MIMEMultipart('alternative') msgRoot.attach(msgAlternative) msgText = MIMEText(mail_body_plain, 'plain', 'utf-8') msgAlternative.attach(msgText) msgText = MIMEText(mail_body_html, 'html','utf-8') msgAlternative.attach(msgText) smtp = smtplib.SMTP() smtp.connect(smtp_server) smtp.login(smtp_user,smtp_pass) smtp.sendmail(strFrom, strTo, msgRoot.as_string()) smtp.quit()
注：修改成系统python实际路径&ldquo;#!/usr/local/bin/python&rdquo;(第一行)
#chmod +x /etc/keepalived/Mailnotify.py
#/usr/local/haproxy/sbin/haproxy -f /usr/local/haproxy/etc/haproxy.cfg
#service keepalived start

8、查看VRRP通讯记录
#tcpdump vrrp

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
15:49:05.270017 IP 192.168.0.20 > VRRP.MCAST.NET: VRRPv2, Advertisement, vrid 50, prio 100, authtype simple, intvl 1s, length 20
 

四、Haproxy界面
访问http://192.168.0.20/admin-status，输入帐号admin密码123456进入管理监控平台。

haproxy-1.4.9以后版本最大的亮点是添加了手工启用/禁用功能，对升级变更应用时非常有用。

五、邮件通知