Nagios监控linux服务器

原始出处

Nagios监控linux服务器

平台及所用组件,

监控服务器:RHEL5(192.168.0.20)+nagios-3.0.5+ nagios-plugins-1.4.11+ nrpe_2.8.1

被监控端RHEL5 (192.168.0.21)+ nagios-plugins-1.4.11+ nrpe_2.8.1

内容简介

本文档介绍nagios监控linux服务器, 因为监控都是依靠插件去完成的，而监控linux主要使用NRPE插件,本文首先简单介绍一下NRPE监控基础,及监控过程,然后一步步的配置一个实例实现监控linux服务器

1.NRPE监控插件基础

NRPE总共由两部分组成:

check_nrpe插件,运行在监控主机上。

NRPE daemon,运行在远程的linux主机上(通常就是被监控机)

整个的监控过程:(如下图)

当Nagios需要监控某个远程linux主机的服务或者资源情况时：

1).nagios运行check_nrpe插件,我们要在nagios配置文件中告诉它要检查什么.

2).check_nrpe插件会通过SSL连接到远程的NRPE daemon.

3).NRPE daemon会运行相应的nagios插件来执行检查本地资源或服务.

4).NRPE daemon将检查的结果返回给check_nrpe插件,插件将其递交给nagios做处理.

注意:NRPE daemon需要nagios插件安装在远程被监控linux主机上,否则,daemon不能做任何的监控. 别外因为它们间的通信是加密的SSL,所以在编译安装时都要加上选项, ./configure --enable-ssl --with-ssl-lib=/lib/,否则也会出错.

2.配置监控端

1.安装nagios

rpm -qa |grep gd

rpm -ql gd-devel-2.0.28-5.4E.el4_6.1

cd nagios-3.0.5

./configure --prefix=/usr/local/nagios --with-command-group=nagcmd --with-gd-lib=/usr/lib --with-gd-inc=/usr/include

make all

make install

make install-init

make install-config

make install-commandmode

make install-webconf #可以自动配置httpd.conf

2.安装nagios-plugins

cd nagios-plugins-1.4.11

./configure --with-nagios-user=nagios --with-nagios-group=nagios --enable-redhat-pthread-workaround

make

make install

3.安装NRPE

cd nagios-nrpe_2.8.1

./configure #默认自动添加了openssl

#因为传送过程要加密,如果后面make报错,加如下参数

rpm -qa| grep ssl

openssl-devel-0.9.7a-43.17.el4_6.1

rpm -ql openssl-devel-0.9.7a-43.17.el4_6.1 | more

./configure --enable-ssl --with-ssl-lib=/lib/(当然前提要有openssl)

make all

make install-plugin

4.commands.cfg定义外部构件nrpe

vi /usr/local/nagios/etc/objects/commands.cfg

#添加

#check nrpe

define command{

command_name check_nrpe

command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$

}

5.配置要监控的linux主机

vi /usr/local/nagios/etc/nagios.cfg

#中间添加

cfg_file=/usr/local/nagios/etc/objects/mylinux.cfg

6.新建mylinux.cfg 设置监控内容

vi /usr/local/nagios/etc/objects/mylinux.cfg

define host{

use linux-server

host_name mylinux

alias mylinux

address 192.168.0.21(客户端IP既被监控的IP)

}

define service{

use generic-service

host_name mylinux

service_description check-swap

check_command check_nrpe!check_swap

}

define service{

use generic-service

host_name mylinux

service_description check-load

check_command check_nrpe!check_load

}

define service{

use generic-service

host_name mylinux

service_description check-disk

check_command check_nrpe!check_had1

define service{

use generic-service

host_name mylinux

service_description check-users

check_command check_nrpe!check_users

}

define service{

use generic-service

host_name mylinux

service_description otal_procs

check_command check_nrpe!check_total_procs

}

6.其它设置

chkconfig --add nagios #配置机器启动时自动启动Nagios

chkconfig nagios on

/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg #检查Nagios配置文件

vi /etc/selinux/config #关闭SELinux

SELINUX=disabled

service iptables stop #关闭SELinux,或打开80,5666端口

service nagios start

3.配置被监控端

1.安装nagios-plugin

useradd nagios

passwd nagios

tar -zxvf nagios-plugins-1.4.12.tar.gz

cd nagios-plugins-1.4.12

./configure --with-nagios-user=nagios --with-nagios-group=nagios --enable-redhat-pthread-workaround

Make

make install

2.改变主目录权限

chown –R nagios.nagios /usr/local/nagios

[root@client nagios]# ll

drwxr-xr-x 2 nagios nagios 4096 Jun 1 00:07 libexec

drwxr-xr-x 3 nagios nagios 4096 Jun 1 00:07 share

3.安装客户端的nrpe

tar -zxvf nagios-nrpe_2.8.1.orig.tar.gz

cd nagios-nrpe_2.8.1

./configure (会自动加载SSL)

#如果后面make报错,加如下参数

./configure --enable-ssl --with-ssl-lib=/usr/lib/(当然前提要有openssl)

make all

make install-plugin

make install-daemon

make install-daemon-config

4.配置nrpe信息

vi /usr/local/nagios/etc/nrpe.cfg

allowed_hosts=192.168.0.20,127.0.0.1,192.168.0.99

5.启动nrpe

/usr/local/nagios/bin/nrpe -c /usr/local/nagios/etc/nrpe.cfg –d

#或

vi /etc/rc.d/rc.local

/usr/local/nagios/bin/nrpe -c /usr/local/nagios/etc/nrpe.cfg –d

6.验证nrpe

netstat -an | grep 5666

tcp 0 0 0.0.0.0:5666 0.0.0.0:* LISTEN

/usr/local/nagios/libexec/check_nrpe -H 127.0.0.1

NRPE v2.8.1

#服务端测试

/usr/local/nagios/libexec/check_nrpe -H l92.168.0.21

NRPE v2.8.1

#常见错误

/usr/local/nagios/libexec/check_nrpe -H 127.0.0.1

CHECK_NRPE: Error - Could not complete SSL handshake.

配置allowed_hosts=192.168.0.20,127.0.0.1,192.168.0.99,然后kill进程再重启就OK了

2./usr/local/nagios/libexec/check_nrpe -H 127.0.0.1

Connection refused by host

Nrpe进程没有启动

7.配置监控对像(关键)

由监控原理可知被监控端做监控然后传给监控服务器绘总,设置监控详细参数主要是设置被监控端的nrpe.cfg文件

可以看到里面监控对象

vi /usr/local/nagios/etc/nrpe.cfg

command[check_users]=/usr/local/nagios/libexec/check_users -w 5 -c 10

command[check_load]=/usr/local/nagios/libexec/check_load -w 15,10,5 -c 30,25,20

command[check_hda1]=/usr/local/nagios/libexec/check_disk -w 20 -c 10 -p /dev/hda1

command[check_zombie_procs]=/usr/local/nagios/libexec/check_procs -w 5 -c 10 -s Z

command[check_total_procs]=/usr/local/nagios/libexec/check_procs -w 150 -c 200

command[check_swap]=/usr/local/nagios/libexec/check_swap -w 20% -c 10%

这一步是关键,如果nagios服务器想要监控客户机swap分区,但客户机nrpe.cfg文件没有swap监控对像,这时监控服务器就是报错(NRPE command ‘check_swap’no defined).如下图:其实平时自己写脚本,也是主要配这个地方

到此,就可以监控linux客户机的Disk,swap,users,memory了.

注:附件包含本次实验的所有软件包,配置文件

转载于:https://blog.51cto.com/17610376/195971