LVS+Keepalived+Squid+Nginx高可用负载均衡缓存配置

前言* 随着互联网IT行业的发展，越来越多的企业开始使用开源软件搭建自己的web架构，主流的LVS也得到了广泛的应用，在保证高可用的同时，用户对网站的体验速度也有了很高的要求，这时候需要我们在我们的架构既要满足高并发同时还要求高速度。 今天我们来搭建主流架构Lvs+Keepalived+Squid+Nginx

实施环境及相关软件：

系统：CentOS6.0 x64
Ipvsadm：ipvsadm-1.24.tar.gz
Keepalived：keepalived-1.1.15.tar.gz
Squid：squid-3.1.10
Nginx：nginx-1.2.0.tar.gz
Ip信息：
Lvs-master 192.9.117.139
Lvs-backup 192.9.117.140
Lvs-vip    192.9.117.145
Squid_1 192.9.117.141
Squid_2 192.9.117.142
Nginx_1 192.9.117.143
Nginx_1 192.9.117.144

网络架构图：

一、Lvs+Keepalived安装

1、下载源码包
cd /usr/src/
wget http://www.linuxvirtualserver.org/software/kernel-2.6/ipvsadm-1.24.tar.gz
wget http://www.keepalived.org/software/keepalived-1.1.15.tar.gz
2、建立软链接
ln -s /usr/src/kernels/2.6.* /usr/src/linux
3、安装ipvsadm、keepalived
cd /usr/src/ && tar xzvf ipvsadm-1.24.tar.gz &&cd ipvsadm-1.24
&& make && make install
cd /usr/src/  &&  tar -xzvf keepalived-1.1.15.tar.gz  &&
cd keepalived-1.1.15  && ./configure  &&  make  &&  make install
4、配置keepalived
cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
mkdir -p /etc/keepalived
cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/
cp /usr/local/sbin/keepalived /usr/sbin/

5、修改keepalived配置文件

vi /etc/keepalived/keepalived.conf ，根据实际情况修改：

! Configuration File for keepalived
global_defs {
   notification_email {
      [email protected]
   }
   notification_email_from [email protected]
   smtp_server 127.0.0.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
}
# VIP1
vrrp_instance VI_1 {
    state MASTER //备份服务器改成BACKUP
    interface eth0
    lvs_sync_daemon_inteface eth0
    virtual_router_id 51
    priority 100 //备份服务器改成90
    advert_int 5
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.9.117.145 //VIP地址
    }
}
virtual_server 192.9.117.145 80 {
    delay_loop 6
    lb_algo rr //lvs算法
    lb_kind DR
   persistence_timeout 60
protocol TCP
    real_server 192.9.117.141 80 {
        weight 100
        TCP_CHECK {
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
 real_server 192.9.117.142 80 {
        weight 100
        TCP_CHECK {
        connect_timeout 10
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
        }
    }
}

同理Lvs_backup也如上安装，并修改参数，Lvs+keepalived配置完毕后，启动keepalived, /etc/init.d/keepalived start 即可！然后在squid_1、squid_2分别执行realserver.sh脚本

二、Squid安装

1、给squid指定单独的缓存目录:
mkdir -p /data/squid &&chown -R squid:squid /data/squid/
2、设置squid日志路径:
mkdir -p /data/logs/squid/ && chown -R squid:squid /data/logs/squid/
3、安装squid
 yum install squid -y 即可。
4、修改squid.conf配置文件，贴一个简单的squid部分配置文件
####http port 2012 05 20
http_port 0.0.0.0:80 vhost vport
cache_peer 192.9.117.143 parent 80 0 no-digest no-query originserver
cache_peer 192.9.117.144 parent 80 0 no-digest no-query originserver
cache_mem 2048 MB
maximum_object_size_in_memory 4096 KB
cache_dir aufs /data/squid 4000 16 512
coredump_dir /data/squid
启动squid /etc/init.d/squid start 即可！
配置完两台squid并启动。并且都可以看到lo:0接口ip地址为VIP地址：

三、Nginx安装

分别在192.9.117.143、192.9.117.144安装nginx，并配置好相应的测试页面,最后访问LVS-vip结果如下 http://192.9.117.145/

查看lvs转发状态