前提先自行安装好Apache+php
测试环境
主监控机：CentOS 6.2 172.16.1.8
被监控机：CentOS 6.2 172.16.5.11
主监控机设置:
1、安装epel
# cat /etc/issue
CentOS release 6.2 (Final)
Kernel \r on an \m
# rpm -ivh rpm -ivh http://dl.iuscommunity.org/pub/ius/stable/Redhat/6/x86_64/epel-release-6-5.noarch.rpm 这里应该对应你服务器的版本
2、安装nagios、nagios-plugin与nrpe (nagios 3.3.1版本)
# yum install nagios nagios-plugins nagios-plugins-all nagios-plugins-nrpe nrpe
3、创建一个nagiosadmin 的用户用于Nagios的WEB接口登录，用户认证配置useradd nagiosadmin
# htpasswd -c /etc/nagios/passwd nagiosadmin
New password:
Re-type new password:
Adding password for user nagiosadmin
4、修改cgi.cfg文件，找到use_authentication=1 这行，把1改成0
#find -name cgi.cfg -print 查找
#vi /etc/nagios/cgi.cfg
5、启动apache与nagios
# /etc/init.d/httpd restart
# /etc/init.d/nagios start
6、登陆http://localhost/nagios/，输入用户密码后查看是否正常运行
注：别忘记了nagios后面那个/
被监控机设置:
1、安装需要软件
# yum install nagios-plugins nagios-plugins-nrpe nrpe
2、配置nrpe
# vi /etc/nagios/nrpe.cfg 修改监控机的地址或域名
allowed_hosts=127.0.0.1,192.168.1.8
3、修改/etc/hosts.allow增加监控机ip
# echo ‘nrpe:192.168.1.8′ >> /etc/hosts.allow
4、检查 NRPE 是否正常：
监控机上：
# /usr/lib64/nagios/plugins/check_nrpe -H 192.168.5.11
NRPE v2.12
查看相应的端口：netstat -an |grep 5666
防火墙开启5666 允许局域网IP或固定IP连接
5、启动 NRPE 守护进程：
# /usr/sbin/nrpe -c /etc/nagios/nrpe.cfg –d 或者
#/etc/init.d/nrpe start
6、关闭selinux：
#setenforce 0
在回到监控机：
添加nrpe的定义
# vi commands.cfg
# ‘check_nrpe’ command definition
define command{
command_name check_nrpe
command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
}
增加主机监控配置项www.cfg

######definehosts###################################definehost{host_namecancer-ts4address172.16.5.4check_commandcheck-host-alivecheck_interval5max_check_attempts2contact_groupsadmins}definehost{host_namecancer-ts11address172.16.5.11check_commandcheck-host-alivecheck_interval5max_check_attempts2contact_groupsadmins}definehost{host_namecancer-ts12address172.16.5.12check_commandcheck-host-alivecheck_interval5max_check_attempts2contact_groupsadmins}definehost{host_namecancer-hz4address172.16.3.4check_commandcheck-host-alivecheck_interval5max_check_attempts2contact_groupsadmins}definehost{host_namecancer-hz5address172.16.3.5check_commandcheck-host-alivecheck_interval5max_check_attempts2contact_groupsadmins}definehost{host_namecancer-hz12address172.16.3.12check_commandcheck-host-alivecheck_interval5max_check_attempts2contact_groupsadmins}definehost{host_namecancer-hz13address172.16.3.13check_commandcheck-host-alivecheck_interval1max_check_attempts2contact_groupsadmins}########defineservice######################defineservice{host_namecancer-ts4,cancer-ts11,cancer-ts12,cancer-hz4,cancer-hz5,cancer-hz12,cancer-hz13service_descriptionUserscheck_period24x7normal_check_interval5retry_check_interval2max_check_attempts5notification_period24x7contact_groupsadminscheck_commandcheck_nrpe!check_users}defineservice{host_namecancer-ts4,cancer-ts11,cancer-ts12,cancer-hz4,cancer-hz5,cancer-hz12,cancer-hz13service_descriptionLoadcheck_period24x7normal_check_interval5retry_check_interval2max_check_attempts5notification_period24x7contact_groupsadminscheck_commandcheck_nrpe!check_load}defineservice{host_namecancer-ts4,cancer-ts11,cancer-ts12,cancer-hz4,cancer-hz5,cancer-hz12,cancer-hz13service_descriptiondiskcheck_period24x7normal_check_interval5retry_check_interval2max_check_attempts5notification_period24x7contact_groupsadminscheck_commandcheck_nrpe!check_hda1}defineservice{host_namecancer-ts11,cancer-ts12,cancer-ts4,cancer-hz4,cancer-hz5,cancer-hz13,cancer-hz12service_descriptionnginxcheck_period24x7normal_check_interval5retry_check_interval2max_check_attempts5notification_period24x7contact_groupsadminscheck_commandcheck_nrpe!check_nginx}

并把www.cfg添加到nagios主配置项
# echo “cfg_file=/etc/nagios/objects/www.cfg” >> /etc/nagios/nagios.cfg
其他机器如法炮制即可