Cacti是由php开发的网页，运行于LA/NMP平台，可利用SNMP获取数据，周期性的执行能够取得数据的命令，将取回的数据保存至rrd文件当中，利用rrdtool绘出图形。
snmp原理详解
http://blog.csdn.net/shanzhizi/article/details/11606767
http://www.cnblogs.com/xdp-gacl/p/3978825.html
rrdtool原理详解
http://blog.liuts.com/post/215/
LAMP环境已经编译搭建
虚拟主机配置
<VirtualHost *:80>
DocumentRoot "/web/vhosts/cacti"
DirectoryIndex index.shtml index.html index.php
ErrorLog "logs/cacti_error.log"
CustomLog "logs/cacti_access.log" common
ProxyRequests Off ProxyPassMatch^/(.*\.php)$fcgi://127.0.0.1:9000/web/vhosts/cacti/$1
<Directory /web/vhosts/cacti >
Options FollowSymLinks Includes
AllowOverride All
Require all granted
</Directory>
</VirtualHost>安装snmp并配置
# yum -y install rrdtool net-snmp net-snmp-libs net-snmp-utils
修改配置文件/etc/snmp/snmpd.conf中的默认community,后启动服务
eg: com2sec notConfigUser 127.0.0.1 mypublic
# chkconfig snmpd on
# service snmpd start 安装cacti，解压安装包到虚拟主机的根目录
# mkdir -p /web/vhosts/
# tar xvf cacti-0.8.8h.tar.gz -C /web/vhosts/
# ln -sv /web/vhosts/cacti-0.8.8h /web/vhosts/cacti初始化数据，更新授权
# cd /web/vhosts/cacti
# mysqladmin create cactidb
# mysql cactidb < cacti.sql
# mysql -e "GRANT ALL ON cactidb.* to cactiuser@localhost IDENTIFIED BY 'cactipasswd'"
# mysqladmin flush-privileges创建系统用户cactiuser，修改cacti安装目录下rra和log目录的属主属组
# useradd cactiuser
# id cactiuser
uid=501(cactiuser) gid=501(cactiuser) groups=501(cactiuser)
# chown -R cactiuser:cactiuser rra log修改Cacti配置文件中的mysql连接参数
# cat include/config.php
$database_type = "mysql";
$database_default = "cactidb";
$database_hostname = "localhost";
$database_username = "cactiuser";
$database_password = "cactipasswd";
$database_port = "3306";
$database_ssl = false;
$url_path = "/"; #此处修改了cacti默认访问路径，不需要在访问地址后加/cacti以cactiuser用户身份添加cacti收集数据的任务计划
# echo '*/5 * * * * /usr/local/php/bin/php /web/vhosts/cacti/poller.php &>/dev/null' > /var/spool/cron/cactiuser
# echo "date.timezone = Asia/Shanghai" >> /etc/php.ini 修改php时区
# hwclock -w #同步硬件时间到系统
# hwclock
Mon 25 Jul 2016 06:57:17 PM CST -0.347178 seconds
# date
Mon Jul 25 18:57:20 CST 2016
# service httpd restart
# service snmpd restart在浏览器中输入http://ip按照提示进行安装 
编辑脚本获取TCP数据
# cd /web/vhosts/cacti/scripts/
# cat tcpcon.sh
#!/bin/bash
#$1: hostname/ip
#$2:snmp community
SNMPNETSTAT=/usr/bin/snmpnetstat
TF=`mktemp /tmp/$1_tcpcon.XXXXXXX`
$SNMPNETSTAT -v 2c -c $2 -Can -Cp tcp $1 > $TF
EST=`grep -i 'established' $TF |wc -l`
TWAIT=`grep -i 'timewait' $TF |wc -l`
SYNRECV=`grep -i 'synreceived' $TF |wc -l`
echo -n "established:$EST"
echo -n "timewait:$TWAIT"
echo -n "synreceived:$SYNRECV"Console -> Data Input Methods -> (Edit)
定义Data Input Methods，添加SNMP-TCP connections，数据收集方法为脚本，脚本路径为cacti安装目录下的tcpcon.sh，并传递两个参数
Console -> Data Templates -> (Edit)
定义数据模板，关联数据输入方法，添加3个数据源
Console -> Data Sources -> (Edit)定义数据源
Console -> Graph Templates -> (Edit)定义图像模板
