一、keepalived和haproxy

1、keepalived

Keepalived的作用是检测服务器的健康状态,在所有可能出现单点故障的地方为其提供高可用。如果有一台服务器死机,或工作出现故障,Keepalived将检测到,并将有故障的服务器从系统中剔除,当服务器工作正常后Keepalived自动将服务器加入到服务器群中,这些工作全部自动完成,不需要人工干涉,需要人工做的只是修复故障的服务器。

   keepalived的核心是vrrp,它是通过脚本来调用服务的,所以在keepalived的使用中,仅需关心两点:配置文件(/etc/keepalived/keepalived.conf)和服务脚本(/etc/rc.d/init.d/keepalived)

2、haproxy

   haproxy是一个七层的负载均衡高度器,和nginx是属于一个层次上的,而lvs是一个四层的负载均衡高度器,它最多只能工作在TCP\IP协议栈上,所以对于代理转发,haproxy做的可以比lvs更细腻

HAProxy提供高可用性、负载均衡以及基于TCP和HTTP应用的代理,支持虚拟主机,它是免费、快速并且可靠的一种解决方案。HAProxy特别适用于那些负载特大的web站点,这些站点通常又需要会话保持或七层处理。HAProxy运行在当前的硬件上,完全可以支持数以万计的并发连接。并且它的运行模式使得它可以很简单安全的整合进您当前的架构中,同时可以保护你的web服务器不被暴露到网络上。

二、拓扑图

keepalived+haproxy双主高可用负载均衡_第1张图片

三、前端配置

1、ha1配置(172.16.7.10)

(1)配置keepalived

[root@ha1 ~]# yum -y install keepalived     #安装keepalived
[root@ha1 ~]# vim /etc/keepalived/keepalived.conf  #修改配置文件
! Configuration File for keepalived
global_defs {
   notification_email {    #通知邮件地址
     root@localhost
     shuishui@localhost
   }
   notification_email_from warning@localhost
   smtp_server 127.0.0.1        #邮件服务器地址
   smtp_connect_timeout 30
   router_id LVS_DEVEL_shuishui
}
#
vrrp_script chk_haproxy {
        script "killall -0 haproxy"    #服务探测,返回0说明服务是正常的
        interval 1    #每隔1秒探测一次
        weight 2      #haproxy上线,权重加2;下线,权重减2
}
#
vrrp_instance VI_1 {        #双主实例1
    state MASTER            #ha1(172.16.7.10)为主,ha2(172.16.7.100)为备
    interface eth0
    virtual_router_id 88    #实例1的VRID为88
    garp_master_delay 1
    priority 100            #主(172.16.7.10)的优先级为100,从的(172.16.7.100)优先级为99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
#
    virtual_ipaddress {
        172.16.7.88/16 dev eth0    #实例1的VIP
    }
    track_interface {
        eth0
    }
#
    track_script {        #脚本追踪
        chk_haproxy
    }
    notify_master "/etc/keepalived/notify.sh master"
    notify_backup "/etc/keepalived/notify.sh backup"
    notify_fault "/etc/keepalived/notify.sh fault"
}
vrrp_instance VI_2 {
    state BACKUP        #实例2在ha1(172.16.7.10)上是备,在ha2(172.16.7.100)上是主
    interface eth0
    virtual_router_id 188    #实例2的VRID是188
    garp_master_delay 1
    priority 200             #实例2在ha1上的优先级是200,在ha2上的优先级是201
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
#
    virtual_ipaddress {
        172.16.7.188/16 dev eth0    #实例2的VIP
    }
    track_interface {
        eth0
    }
#
    track_script {        #脚本追踪
        chk_haproxy
    }
}

为ha1的keepalived提供脚本文件:

[root@ha1 keepalived]# pwd
/etc/keepalived
[root@ha1 keepalived]# vim notify.sh
#!/bin/bash
# Author: MageEdu    脚本使用请清明出处
# description: An example of notify script
#
vip=172.16.7.88
contact='root@localhost'
notify() {
    mailsubject="`hostname` to be $1: $vip floating"
    mailbody="`date '+%F %H:%M:%S'`: vrrp transition, `hostname` changed to be $1"
    echo $mailbody | mail -s "$mailsubject" $contact
}
case "$1" in
    master)
        notify master
        /etc/rc.d/init.d/haproxy start
        exit 0
    ;;
    backup)
        notify backup
        /etc/rc.d/init.d/haproxy stop
        exit 0
    ;;
    fault)
        notify fault
        /etc/rc.d/init.d/haproxy stop
        exit 0
    ;;
    *)
        echo 'Usage: `basename $0` {master|backup|fault}'
        exit 1
    ;;
esac
#给脚本执行权限
[root@ha1 keepalived]# chmod +x notify.sh

(2)配置haproxy

[root@ha1 ~]# yum -y install haproxy    #安装haproxy
[root@ha1 ~]# vim /etc/haproxy/haproxy.cfg     #修改配置文件
global
    log         127.0.0.1 local2
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    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
    mode                    http    #指定haproxy的工作模式为http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close    #当客户端超时时,允许服务器关闭连接
    option forwardfor       except 127.0.0.0/8    #在响应头部加入forwardfor
    option                  redispatch    #在使用了基于cookie的会话保持的时候,通常需要
                                          #加这么一项,一旦后端某一server宕机时,能够将
                                          #其会话重新派发到其它的upstream servers
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 10000    #最大并发连接数
#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend  proxy *:80    #前端代理
    acl url_static       path_beg       -i /static /p_w_picpaths /javascript /stylesheets
    acl url_static       path_end       -i .html .jpg .gif .png .css .js
    acl dynamic_content  path_end       -i .php
    use_backend static          if url_static
    default_backend             dynamic
#---------------------------------------------------------------------
# static backend for serving up p_w_picpaths, stylesheets and such
#---------------------------------------------------------------------
backend static    #后端静态服务器
    balance     roundrobin
    server      web1  172.16.7.201:80 inter 3000 rise 2 fall 3 check maxconn 5000
#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend dynamic    #后端动态服务器
    balance     roundrobin
    server      web2  172.16.7.202:80 inter 3000 rise 2 fall 3 check maxconn 5000
    server      web3  172.16.7.200:80 inter 3000 rise 2 fall 3 check maxconn 5000
listen statistics
        mode http
        bind *:8080    #把stats页面绑定到8080端口
        stats enable   #开启stats功能
        stats auth admin:admin    #认证的用户名和密码
        stats uri /admin?stats    #指定uri访问路径
        stats hide-version        #为了安全(版本bug),隐藏版本信息
        stats admin if TRUE       #如果认证通过了就允许管理
        stats refresh 5s        #页面5秒刷新一次
        acl allow src 172.16.0.0/16    #定义访问控制列表
        tcp-request content accept if allow
        tcp-request content reject

2、ha2配置(172.16.7.100)

(1)配置keepalived

[root@ha2 ~]# yum -y install keepalived     #安装keepalived
[root@ha2 ~]# vim /etc/keepalived/keepalived.conf  #修改配置文件
! Configuration File for keepalived
global_defs {
   notification_email {
     root@localhost
     shuishui@localhost
   }
   notification_email_from root@localhost
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL_shuishui
}
#
vrrp_script chk_haproxy {
        script "killall -0 haproxy"
        interval 1
        weight 2
}
#
vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 88
    garp_master_delay 1
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
#
    virtual_ipaddress {
        172.16.7.88/16 dev eth0
    }
    track_interface {
        eth0
    }
#
    track_script {
        chk_haproxy
    }
}
#
vrrp_instance VI_2 {
    state MASTER
    interface eth0
    virtual_router_id 188
    garp_master_delay 1
    priority 201
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
#
    virtual_ipaddress {
        172.16.7.188/16 dev eth0
    }
    track_interface {
        eth0
    }
#
    track_script {
        chk_haproxy
    }
    notify_master "/etc/keepalived/notify.sh master"
    notify_backup "/etc/keepalived/notify.sh backup"
    notify_fault "/etc/keepalived/notify.sh fault"
}
#
#
#脚本同ha1的(脚本里的vip改为172.16.7.188),最后给执行权限

(2)配置haproxy

   因为ha1的haproxy与ha2的haproxy是相同的,都是将服务代理至后端服务器,所以直接scp就可以

[root@ha1 ~]# scp /etc/haproxy/haproxy.cfg [email protected]:/etc/haproxy/

3、启动keepalived并测试

(1)ha1

keepalived+haproxy双主高可用负载均衡_第2张图片

(2)ha2

keepalived+haproxy双主高可用负载均衡_第3张图片

(3)关闭ha1的haproxy服务测试VIP飘移

keepalived+haproxy双主高可用负载均衡_第4张图片

(4)查看ha2,是否接收到了ha1飘过来的VIP

keepalived+haproxy双主高可用负载均衡_第5张图片

四、后端配置

1、配置web1(172.16.7.201),静态的

[root@web1 ~]# yum -y install httpd
[root@web1 ~]# cd /var/www/html/
[root@web1 html]# vim index.html

Welcome to web1(172.16.7.201)

[root@web1 html]# service httpd start

2、配置web2(172.16.7.202),动态的

[root@web2 ~]# yum -y install httpd php
[root@web2 ~]# cd /var/www/html/
[root@web2 html]# vim index.php

Welcome to web2(172.16.7.202)

[root@web2 html]# service httpd start

3、配置web3(172.16.7.200),动态的

[root@web3 ~]# yum -y install httpd php
[root@web3 ~]# cd /var/www/html/
[root@web3 html]# vim index.php

Welcome to web3(172.16.7.200)

[root@web3 html]# service httpd start

五、测试

1、keepalived的高可用

   上面测试过了,当haproxy服务挂掉的时候,VIP可以飘走;当keepalived服务挂掉的时候,VIP也可以飘走,高可用功能实现

2、haproxy动静分离机制

(1)请求静态内容

   首先在web1(172.16.7.201)的网页目录下放入1.jpg

keepalived+haproxy双主高可用负载均衡_第6张图片

(2)请求动态内容

keepalived+haproxy双主高可用负载均衡_第7张图片

(3)haproxy统计页面的输出

   ①、URI及安全验证

keepalived+haproxy双主高可用负载均衡_第8张图片

   ②、haproxy统计页面

keepalived+haproxy双主高可用负载均衡_第9张图片