chbo_yang

nagios配置详解

前言：

文中未标明时，所有陪着之都是在nagios_server上的配置！

配置流程:

nagios.cfg-->hosts.cfg-->services.cfg-->command.cfg

创建hosts.cfg文件来定义主机和主机组
创建services.cfg文件来定义服务
用默认的contacts.cfg文件来定义联系人和联系人组
用默认的commands.cfg文件来定义命令
用默认的timeperiods.cfg来定义监控时间段
用默认的templates.cfg文件作为资源引用文件

/usr/local/nagios/etc/ 目录结构

[root@chboc etc]# tree /usr/local/nagios/etc

/usr/local/nagios/etc

|-- cgi.cfg

|-- htpasswd.users

|-- nagios.cfg

|-- nagios.cfg.bak

|-- nrpe.cfg

|-- objects

| |-- commands.cfg

| |-- contacts.cfg

| |-- hosts.cfg 定义监控remote_hosts和remote_hosts_group

| |-- hosts.cfg.bak

| |-- localhost.cfg

| |-- printer.cfg

| |-- services.cfg 定义被动模式的监控服务，监控remote_linux的本地资源

| |-- switch.cfg

| |-- templates.cfg

| |-- timeperiods.cfg

| `-- windows.cfg

|-- resource.cfg

`-- services 定义主动模式的监控服务，监控remote_linux的对外提供的服务

`-- web.cfg

注意！！创建hosts.cfg,services.cfg,services文件和目录时，修改他们的属主和属组！！

nagios.cfg

[root@chboc etc]# diff nagios.cfg nagios.cfg.bak

34,35d33

< cfg_file=/usr/local/nagios/etc/objects/services.cfg

< cfg_file=/usr/local/nagios/etc/objects/hosts.cfg

38c36

< #cfg_file=/usr/local/nagios/etc/objects/localhost.cfg

---

> cfg_file=/usr/local/nagios/etc/objects/localhost.cfg

54c52

< cfg_dir=/usr/local/nagios/etc/services

---

> #cfg_dir=/usr/local/nagios/etc/servers

可简单理解为：nagios.cfg只是指定nagios启动时加载哪些目录和文件而已。
修改nagios.cfg主配置文件，添加services.cfg,hosts.cfg，使得nagios启动过程中自动加载hosts.cfg和services.cfg中的内容。
nagios监控一般都是用来监控remote_linux上面的服务，所以在此将cfg_file=/usr/local/nagios/etc/objects/localhost.cfg注释掉。
nagios的监控模式简单分为主动模式和被动模式（NRPE）。

主动模式：一般用来监控web服务，数据库等这些对外提供服务的监控，如：httpd，mysqld，sshd等

被动模式：一般用来监控本地资源，例如负载，内存，硬盘，虚拟内存，磁盘IO，温度，风扇等的监控（我们也可以通过snmp实现监控部分系统资源）。

主动模式和被动模式是可以相互互换的，没有绝对性。

hosts.cfg

[root@chboc objects]# egrep -v "^$|^#" hosts.cfg

define host{

use linux-server

host_name lnmp

alias 198-lnmp

address 192.168.1.198

}

define host{

use linux-server

host_name lamp

alias 199-lamp

address 192.168.1.199

}

define hostgroup{

hostgroup_name linux-servers ; The name of the hostgroup

alias Linux Servers ; Long name of the group

members lnmp,lamp ; Comma separated list of hosts that belong to this group

}

定义所要监控的remote_linux，并将其分组。
生成hosts.cfg文件：
head -51 localhost.cfg >hosts.cfg
chown nagios.nagios /usr/local/nagios/etc/objects/hosts.cfg

services.cfg -->command.cfg

+--->nrpe.cfg(remote_linux)

[root@chboc objects]# egrep -v "^$|^#" services.cfg

define service {

use generic-service

host_name lnmp

service_description Disk Partition

check_command check_nrpe!check_disk

}

define service {

use generic-service

host_name lnmp

service_description load

check_command check_nrpe!check_load

}

define service {

use generic-service

host_name lnmp

service_description mem

check_command check_nrpe!check_mem

}

define service {

use generic-service

host_name lnmp

service_description swap

check_command check_nrpe!check_swap

}

define service {

use generic-service

host_name lnmp

service_description iostat

check_command check_nrpe!check_iostat

}

services.cfg 我采用NRPE的被动模式，通过nagios_server主机上的check_nrpe插件，调用运行在renmote_linux上的NRPE daemon监控renmote_linux的本地资源。
NRPE原理
NRPE 总共由两部分组成：
check_nrpe 插件，位于监控主机上
NRPE daemon，运行在远程的Linux主机上(通常就是被监控机)
按照上图，整个的监控过程如下：
当Nagios 需要监控某个远程Linux 主机的服务或者资源情况时：
Nagios 会运行check_nrpe 这个插件，告诉它要检查什么；
check_nrpe 插件会连接到远程的NRPE daemon，所用的方式是SSL；
NRPE daemon 会运行相应的Nagios 插件来执行检查；
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 插件安装在远程的Linux主机上，否则，daemon不能做任何的监控

command.cfg

--------------------------------------------------------------------------

[root@chboc objects]# tail -4 commands.cfg

define command{

command_name check_nrpe

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

}

nrpe.cfg(remote_linux)

------------------------------------------------------------------------log_facility=daemon

pid_file=/var/run/nrpe.pid

server_port=5666

nrpe_user=nagios

nrpe_group=nagios

allowed_hosts=127.0.0.1,192.168.1.201

dont_blame_nrpe=0

debug=0

command_timeout=60

connection_timeout=300

command[check_load]=/usr/local/nagios/libexec/check_load -w 15,10,6 -c 30,25,20

command[check_mem]=/usr/local/nagios/libexec/check_memory.pl -w 6% -c 3%

command[check_disk]=/usr/local/nagios/libexec/check_disk -w 20% -c 8% -p /

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

command[check_iostat]=/usr/local/nagios/libexec/check_iostat -w 6 -c 10

command[check_port_80]=/usr/local/nagios/libexec/check_tcp -H localhost -p80

/usr/local/nagios/etc/server/web.cfg

[root@chboc etc]# egrep -v "^$|^#" services/web.cfg

define service{

use generic-service

host_name lnmp

service_description blog_url

check_command check_http!-I 192.168.1.198

max_check_attempts 3

normal_check_interval 2

retry_check_interval 1

check_period 24x7

notification_interval 30

notification_period 24x7

notification_options w,u,c,r

contact_groups admins

}

define service{

use generic-service

host_name lnmp

service_description blog_port80

check_command check_tcp!80

max_check_attempts 3

normal_check_interval 2

retry_check_interval 1

check_period 24x7

notification_interval 30

notification_period 24x7

notification_options w,u,c,r

contact_groups admins

}

define service{

use generic-service

host_name lnmp

service_description mysqld_port3306

check_command check_tcp!3306

max_check_attempts 3

normal_check_interval 2

retry_check_interval 1

check_period 24x7

notification_interval 30

notification_period 24x7

notification_options w,u,c,r

contact_groups admins

}

define service{

use generic-service

host_name lnmp

service_description blog_port_80_beidong

check_command check_nrpe!check_port_80

max_check_attempts 3

normal_check_interval 2

retry_check_interval 1

check_period 24x7

notification_interval 30

notification_period 24x7

notification_options w,u,c,r

contact_groups admins

}

主动模式不需要调用check_nrpe插件,直接使用command.cfg里定义的命令即可！

检查配置文件

修改/etc/init.d/nagios启动文件，使其检测时显示详细内容。

vim /etc/init.d/nagios +178

checkconfig)

printf "Running configuration check..."

$NagiosBin -v $NagiosCfgFile > /dev/null 2>&1

if [ $? -eq 0 ]; then

echo " OK."

else

echo " CONFIG ERROR! Check your Nagios configuration."

exit 1

例如：

我们将command.cfg定义的check_nrpe命令注释掉：

[root@chboc objects]# tail -4 commands.cfg

#define command{

# command_name check_nrpe

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

# }

进行检测：

[root@chboc objects]# /etc/init.d/nagios checkconfig

Running configuration check...

Nagios Core 3.5.1

Last Modified: 08-30-2013

License: GPL

Website: http://www.nagios.org

Reading configuration data...

Read main config file okay...

Processing object config file '/usr/local/nagios/etc/objects/commands.cfg'...

Processing object config file '/usr/local/nagios/etc/objects/contacts.cfg'...

Processing object config file '/usr/local/nagios/etc/objects/timeperiods.cfg'...

Processing object config file '/usr/local/nagios/etc/objects/templates.cfg'...

Processing object config file '/usr/local/nagios/etc/objects/services.cfg'...

Processing object config file '/usr/local/nagios/etc/objects/hosts.cfg'...

Processing object config directory '/usr/local/nagios/etc/services'...

Processing object config file '/usr/local/nagios/etc/services/web.cfg'...

Read object config files okay...

Running pre-flight check on configuration data...

Checking services...

Error: Service check command 'check_nrpe' specified in service 'Disk Partition' for host 'lnmp' not defined anywhere!

Error: Service check command 'check_nrpe' specified in service 'blog_port_80_beidong' for host 'lnmp' not defined anywhere!

Error: Service check command 'check_nrpe' specified in service 'iostat' for host 'lnmp' not defined anywhere!

Error: Service check command 'check_nrpe' specified in service 'load' for host 'lnmp' not defined anywhere!

Error: Service check command 'check_nrpe' specified in service 'mem' for host 'lnmp' not defined anywhere!

Error: Service check command 'check_nrpe' specified in service 'swap' for host 'lnmp' not defined anywhere!

Checked 9 services.

Checking hosts...

Warning: Host 'lamp' has no services associated with it!

Checked 2 hosts.

Checking host groups...

Checked 1 host groups.

Checking service groups...

Checked 0 service groups.

Checking contacts...

Checked 1 contacts.

Checking contact groups...

Checked 1 contact groups.

Checking service escalations...

Checked 0 service escalations.

Checking service dependencies...

Checked 0 service dependencies.

Checking host escalations...

Checked 0 host escalations.

Checking host dependencies...

Checked 0 host dependencies.

Checking commands...

Checked 24 commands.

Checking time periods...

Checked 5 time periods.

Checking for circular paths between hosts...

Checking for circular host and service dependencies...

Checking global event handlers...

Checking obsessive compulsive processor commands...

Checking misc settings...

Total Warnings: 1

Total Errors: 6

***> One or more problems was encountered while running the pre-flight check...

Check your configuration file(s) to ensure that they contain valid

directives and data defintions. If you are upgrading from a previous

version of Nagios, you should be aware that some variables/definitions

may have been removed or modified in this version. Make sure to read

the HTML documentation regarding the config files, as well as the

'Whats New' section to find out what has changed.

CONFIG ERROR! Check your Nagios configuration.

在command.cfg添加check_nrpe命令的定义并检测：