http://www.codeweblog.com/nagios%E5%AE%89%E8%A3%85%E9%85%8D%E7%BD%AE/

上线的服务器有时会被人攻击，导致服务不可用，今天安装配置了nagios对上线服务器进行监控，简单记录一下

#安装必要的软件包

yum install -y gcc glibc glibc-common gd gd-devel xinetd openssl-devel

#创建nagios用户及授予目录权限

useradd -s /sbin/nologin nagios

mkdir /usr/local/nagios

chown -R nagios.nagios /usr/local/nagios

#安装nagios

tar xf nagios-4.0.7.tar.gz

cd nagios-4.0.7

./configure --prefix=/usr/local/nagios

make all

make install && make install-init && make install-commandmode && make install-config

chkconfig --add nagios && chkconfig --level 35 nagios on && chkconfig --list nagios

#安装nagios-plugins

tar xf nagios-plugins-2.0.2.tar.gz

cd nagios-plugins-2.0.2

./configure --prefix=/usr/local/nagios

make && make install

#安装apache

tar xf httpd-2.2.23.tar.gz

cd httpd-2.2.23

./configure --prefix=/usr/local/apache2

make && make install

#安装php

tar xf php-5.5.13.tar.gz

cd php-5.5.13

./configure --prefix=/usr/local/php --with-apxs2=/usr/local/apache2/bin/apxs

make && make install

接下来配置apache

#生成nagios密码文件

/usr/local/apache2/bin/htpasswd -c /usr/local/nagios/etc/htpasswd admin

vim /usr/local/apache2/conf/httpd.conf

...

User nagios

Group nagios

...

<IfModule dir_module>

    DirectoryIndex index.html index.php

</IfModule>

...

AddType application/x-httpd-php .php

...

#setting for nagios

ScriptAlias /nagios/cgi-bin "/usr/local/nagios/sbin"

<Directory "/usr/local/nagios/sbin">

     AuthType Basic

     Options ExecCGI

     AllowOverride None

     Order allow,deny

     Allow from all

     AuthName "Nagios Access"

     AuthUserFile /usr/local/nagios/etc/htpasswd             //用于此目录访问身份验证的文件

     Require valid-user

</Directory> Alias /nagios "/usr/local/nagios/share"

<Directory "/usr/local/nagios/share">

     AuthType Basic

     Options None

     AllowOverride None

     Order allow,deny

     Allow from all

     AuthName "nagios Access"

     AuthUserFile /usr/local/nagios/etc/htpasswd

     Require valid-user

</Directory> 

#启动apache

vim /etc/init.d/httpd

#!/bin/sh

#

# Startup script for the Apache Web Server

#

# chkconfig: 345 85 15

# description: Apache is a World Wide Web server.  It is used to serve \

#           HTML files and CGI.

# processname: httpd

# pidfile: /usr/local/apache2/logs/httpd.pid

# config: /usr/local/apache2/conf/httpd.conf

# Source function library.

. /etc/rc.d/init.d/functions

# See how we were called.

case "$1" in

start)

echo -n "Starting httpd: "

daemon /usr/local/apache2/bin/httpd -DSSL

echo

touch /var/lock/subsys/httpd

;;

stop)

echo -n "Shutting down http: "

killproc httpd

echo

rm -f /var/lock/subsys/httpd

rm -f /usr/local/apache2/logs/httpd.pid

;;

status)

status httpd

;;

restart)

$0 stop

$0 start

;;

reload)

echo -n "Reloading httpd: "

killproc httpd -HUP

echo

;;

*)

echo "Usage: $0 {start|stop|restart|reload|status}"

exit 1

esac

exit 0

chmod +x /etc/init.d/httpd

chkconfig httpd on

/etc/init.d/httpd start

接下来配置nagios

#确保admin用户登录后有权限查看信息

vim /usr/local/nagios/etc/cgi.cfg

...

default_user_name=admin

authorized_for_system_information=nagiosadmin,admin

authorized_for_configuration_information=nagiosadmin,admin

authorized_for_system_commands=admin

authorized_for_all_services=nagiosadmin,admin

authorized_for_all_hosts=nagiosadmin,admin

authorized_for_all_service_commands=nagiosadmin,admin

authorized_for_all_host_commands=nagiosadmin,admin

...

#修改nagios主配置文件，将主机的定义都放在/usr/local/nagios/etc/hosts目录中

mkdir /usr/local/nagios/etc/hosts

vim /usr/local/nagios/etc/nagios.cfg

...

cfg_dir=/usr/local/nagios/etc/hosts

...

#添加一个自定义命令

vim /usr/local/nagios/etc/objects/command.cfg

...

# 'check_custom_http' command definition

define command{

        command_name    check_custom_http

        command_line    $USER1$/check_http -4 -N -H $ARG1$ -u $ARG2$

        }

# 'check_dns' command definition

define command{

        command_name    check_dns

        command_line    $USER1$/check_dns -v -H $ARG1$ -a $ARG2$ -w $ARG3$ -c $ARG4$

        }

...

#定义主机组

vim /usr/local/nagios/etc/hosts/group.cfg

define hostgroup{

        hostgroup_name    groupname1

        alias               groupname1

        members             server1 #server1必须在/etc/hosts里有对应的映射

}

#定义主机server1

vim /usr/local/nagios/etc/hosts/server1.cfg

define host{

        use                     linux-server

        host_name               server1

        alias                   server1

        address                 xx.xx.xx.xx

        notification_period     24x7

}

define service{

        use                             local-service         ; Name of service template to use

        host_name                       server1

        service_description             PING

        check_command                   check_ping!100.0,20%!500.0,60% ; 延时100ms丢包率大于20%时，则发出警告通知; 延时500ms丢包率大于60%时，则发出严重错误通知

}

;需要做好本机使用的DNS设置，在/etc/resolv.conf文件中定义

define service{

        use                             local-service         ; Name of service template to use

        host_name                       server1

        service_description             DNS

        check_command                   check_dns!xxx.test.com!xx.xx.xx.xx!4!10 ;连续解析域名发生4次错误，则发出警告通知；连续解析域名发生10次错误，则发出严重错误通知；

}

define service{

        use                             local-service         ; Name of service template to use

        host_name                       server1

        service_description             HTTP

        check_command                   check_custom_http!xxx.abc.com!/somepath/path1  ;注意这里的参数要以!分隔

}

define service{

        use                             local-service         ; Name of service template to use

        host_name                       server1

        service_description             SSH

        check_command                   check_ssh

}

#配置监控出现问题时要通知的联系人

vim /usr/local/nagios/etc/objects/contacts.cfg

define contact{

        contact_name                    user1                ; Short name of user

        use                             generic-contact         ; Inherit default values from generic-contact template (defined above)

        alias                           user1                ; Full name of user

        email                           user1@abc.com  ; <<***** CHANGE THIS TO YOUR EMAIL ADDRESS ******

        }

define contact{

        contact_name                    user2                ; Short name of user

        use                             generic-contact         ; Inherit default values from generic-contact template (defined above)

        alias                           user2                ; Full name of user

        email                           user2@abc.com  ; <<***** CHANGE THIS TO YOUR EMAIL ADDRESS ******

        }

 define contactgroup{

        contactgroup_name       admins

        alias                   Nagios Administrators

        members                 user1,user2

        }   

重启nagios

/etc/init.d/nagios restart

刚才发现nagios监控到服务器异常也没有发邮件通知，查了一下，还需要配置mail命令可发送邮件

yum install mail

vim /etc/mail.rc

...

set from=abc-noreply@abc.com

set smtp=smtp.abc.com

set smtp-auth-user=abc-noreply@abc.com

set smtp-auth-password=somepwd

set smtp-auth=login

...