基于lvs的DR模型搭建高可用的web服务，并部署wordpress，（附有脚本实现健康状态检测的代码） 推荐

# uname -ro
2.6.32-358.el6.i686 GNU/Linux

# ntpdate 172.16.0.1
# crontab -e
no crontab for root - using an empty one
*/5 * * * * /usr/sbin/ntpdate 172.16.0.1

centos6.4自带nfs服务
1.新添加一块磁盘，创建逻辑卷，作为文件共享存储，并挂载/data目录下：具体过程可以参见以前的博客

2.编辑nfs的配置文件/etc/exports，添加如下代码：
# vim /etc/exports
/data   172.16.0.0/16(rw,no_root_squash)
3.启动nfs服务
# service nfs start

4.将NFS文件系统挂分别载至web1和web2服务器的 /usr/local/apache/htdocs目录下，共享web目录
# vim /etc/fstab
172.16.19.1:/data       /usr/local/apache/htdocs                        nfs     defaults,acl    0 0
4.设置共享文件的权限：
#setfacl -m -u:apache:rwx /data
NFS服务基于RPC（远程过程调用）实现网络文件共享

为wordpress授权，使其能够操作数据库
MariaDB [(none)]> grant all privileges on *.* to "wordpress"@'172.16.%.%' identified by 'wordpress';
Query OK, 0 rows affected (0.01 sec)
MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.01 sec)

# vim /usr/local/apache/htdocs/index.php
<?php
phpinfo();
?>

在Director中进行如下配置

1.清空iptables中的规则
# iptables -t filter -F
# yum -y install ipvsadm
　　
2.配置vip
# ifconfig eth0:0 172.16.19.100/16 up

3.配置web1（RS1）
# echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
# echo 1 > /proc/sys/net/ipv4/conf/eth0/arp_ignore
# echo 2 > /proc/sys/net/ipv4/conf/eth0/arp_announce
# echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce

4.隐藏RS1中的VIP，使RS1基于VIP正常与客户端通信
# ifconfig lo:0 172.16.1.100 netmask 255.255.255.255 broadcast 172.16.19.100 up
# route add -host 172.16.19.100 dev lo:0

5.配置web2（RS2）
# echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore
# echo 1 > /proc/sys/net/ipv4/conf/eth0/arp_ignore
# echo 2 > /proc/sys/net/ipv4/conf/eth0/arp_announce
# echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce

6.隐藏RS1中的VIP，使RS1基于VIP正常与客户端通信
# ifconfig lo:0 172.16.1.100 netmask 255.255.255.255 broadcast 172.16.19.100 up
# route add -host 172.16.19.100 dev lo:0
　　
7.在Director中添加集群规则：实现session绑定
# ipvsadm  -A -t 172.16.19.100:80 -s wlc -p 86400
# ipvsadm  -a -t 172.16.19.100:80 -r 172.16.1.10 -g
# ipvsadm  -a -t 172.16.19.100:80 -r 172.16.1.11 -g

1 # cd /data/
　　
下载wordpress
lftp 172.16.0.1:/> get pub/Sources/5.i386/new_lamp/wordpress-3.3.1-zh_CN.zip
2解压wordpress
# uzip wordpress-3.3.1-zh_CN.zip
　　
3.修改wordpress所有文件的权限
# chmod 777  /data/wordpress/*

4 初始化wordpress，并安装部署wordpress
为wordpress创建数据库
# MariaDB [(none)]> create database  wordpress ;
5.为其提供配置脚本
# vim /data/wordpress/wp-config.php
<?php
define('DB_NAME', 'wordpress');
define('DB_USER', 'dis');
define('DB_PASSWORD', 'dis');
define('DB_HOST', '172.16.19.101');
define('DB_CHARSET', 'utf8');
define('DB_COLLATE', '');
define('AUTH_KEY',         '{};kK-laXdILf#|3:0$dX_o( u*.SU9!B2!x,@,Zi!PK^-MQw;=o2P3SCk@0wRoK');
define('SECURE_AUTH_KEY',  '@AkI-VJs-WUVz+]A,n<hClqe.(nJ xsdfqOe:5SxH|UwV:tnU+qyVjCpzG2T/m*j');
define('LOGGED_IN_KEY',    '^8]94US~HTZ,1}K 0q6.Lg.y6,Deq,}7P*PK3I@]x)YxCQ<YVezqs]f!ah>%/* S');
define('NONCE_KEY',        'H wWh@]>p,[7mOdjXtM9hpw@{S[;3pqZN/jVOUSrDF<Kc/fb[5S4J@!)kzk>v428');
define('AUTH_SALT',        'ta:l97{$5{}tuH3&H_JEkR*6f^+AD&Iwv{&v$JXu`/1}dbixz=$sWAtiT]7D(aVt');
define('SECURE_AUTH_SALT', '-GH*Z=2]`6!jEiYfPe$XHk3Y/ItzD,81`4k`zjTj[LOGn&e?y:g?tY|#S%uZzGP$');
define('LOGGED_IN_SALT',   'SLML{Uuo4BX*{!Q.VRA&O3:JaWIYLT>GX{#_OsWS=IJO/bY^PciYjFQ_d{S}F(jp');
define('NONCE_SALT',       'EmkqCx,4<9C;J4]Fr(:2rr4TrgaW4F`R+k,<9K{Et5*i90T+C%#%![Kx^JJGz<$z');
$table_prefix  = 'wp_';
define('WPLANG', 'zh_CN');
define('WP_DEBUG', false);
if ( !defined('ABSPATH') )
define('ABSPATH', dirname(__FILE__) . '/');
require_once(ABSPATH . 'wp-settings.php');
define('WP_ALLOW_REPAIR', true);
?>

# ipvsadm -L -n --connection
IPVS connection entries
pro expire state       source             virtual            destination
TCP 1385:22 NONE        172.16.0.102:0     172.16.19.100:80   172.16.1.11:80
TCP 1313:11 NONE        172.16.19.2:0      172.16.19.100:80   172.16.1.10:80

# ipvsadm -L -n --stats
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes
-> RemoteAddress:Port
TCP  172.16.19.100:80                  310     2958        0   256017        0
-> 172.16.1.10:80                    196     1624        0   132126

# vim checkhealth.sh
#!/bin/bash
#
VIP=172.16.19.100
CPORT=80
FAIL_BACK=127.0.0.1
RS=("172.16.1.10" "172.16.1.11")
declare -a RSSTATUS
RW=("2" "1")
RPORT=80
TYPE=g
CHKLOOP=3
LOG=/var/log/ipvsmonitor.log
addrs() {
ipvsadm -a -t $VIP:$CPORT -r $1:$RPORT -$TYPE -w $2
[ $? -eq 0 ] && return 0 || return 1
}
delrs() {
ipvsadm -d -t $VIP:$CPORT -r $1:$RPORT
[ $? -eq 0 ] && return 0 || return 1
}
checkrs() {
local I=1
while [ $I -le $CHKLOOP ]; do
if curl --connect-timeout 1 http://$1 | grep OK  &> /dev/null; then
return 0
fi
let I++
done
return 1
}
initstatus() {
local I
local COUNT=0;
for I in ${RS[*]}; do
if ipvsadm -L -n | grep "$I:$RPORT" &> /dev/null ; then
RSSTATUS[$COUNT]=1
else
RSSTATUS[$COUNT]=0
fi
let COUNT++
done
}
initstatus
while true; do
let COUNT=0
for I in ${RS[*]}; do
if checkrs $I; then
if [ ${RSSTATUS[$COUNT]} -eq 0 ]; then
addrs $I ${RW[$COUNT]}
[ $? -eq 0 ] && RSSTATUS[$COUNT]=1 && echo "`date +'%F %H:%M:%S'`, $I is back." >> $LOG
fi
else
if [ ${RSSTATUS[$COUNT]} -eq 1 ]; then
delrs $I
[ $? -eq 0 ] && RSSTATUS[$COUNT]=0 && echo "`date +'%F %H:%M:%S'`, $I is gone." >> $LOG
fi
fi
let COUNT++
done
sleep 5
done