男人的胸怀是委屈撑大的。

通过前篇文章《Linux安装Nagios监控系统, perl-fcgi, nginx》看，Nagios的安装比较简单，即使是用nginx来替代apache。复杂的是设置和配置参数的设定。不过你要放松一点，毕竟我们要搞定它，不是吗？那就开始吧：

1：获得最新的安装包，http://www.nagios.org/download
2：以root身份登录服务器，目前最新的版本是3.0.6：
1）nagios，版本2.5：

wget http://nchc.dl.sourceforge.net/sourceforge/nagios/nagios-3.0.6.tar.gz

2）获得nagios插件，版本1.4.3：

wget http://jaist.dl.sourceforge.net/sourceforge/nagiosplug/nagios-plugins-1.4.13.tar.gz

3）获得图库文件：

http://dl.sf.net/nagios/imagepak-base.tar.gz

4）NRPE，版本2.5.2

http://ufpr.dl.sourceforge.net/sourceforge/nagios/nrpe-2.5.2.tar.gz

5）NSCA，版本2.6

http://kent.dl.sourceforge.net/sourceforge/nagios/nsca-2.6.tar.gz

3：切换到root用户：
sudo su

4：解压缩
tar zxvf nagios-2.5.tar.gz

5：建立运行nagios的用户：
adduser nagios

6：建立安装nagios的文件夹，并使这个文件夹的所有者为nagios:nagios
mkdir /usr/local/nagios
chown nagios.nagios /usr/local/nagios

7：确认web服务器的用户
可能会通过web接口执行一些命令，必须确定web服务器以哪个用户运行的，通常为：apache：
grep “^User” /usr/local/apache2/conf/httpd.conf

8：建立命令文件组
这个新的组会包括apache的用户和nagios的用户
pw groupadd nagcmd
pw usermod apache -G nagcmd
pw usermod nagios -G nagcmd
———————————-
cat /etc/group
nagcmd:*:9007:apache,nagios
———————————-

8：运行配置脚本并安装nagios
cd nagios-3.0.6

./configure –prefix=/usr/local/nagios –with-gd-lib=/usr/local/lib –with-gd-inc=/usr/local/include
make all
make install
make install-init
make install-commandmode
make install-config

9：安装nagios-plugins
tar zxvf nagios-plugins-1.4.13.tar.gz
cd nagios-plugins-1.4.13
./configure –prefix=/usr/local/nagios-plugins
make all
make install
安装完成以后在/usr/local/nagios-plugins-plugins会产生一个libexec的目录，将该目录全部移动到/usr/local/nagios目录下即可。
mv /usr/local/nagios-plugins-plugins/libexec/ /usr/local/nagios/

10：imagepak-base.tar.gz的安装
tar –xvzf imagepak-base.tar.gz
解压以后是base目录
mv base/ /usr/local/nagios/share/images/logos/

———————————————————————-
现在开始配置：
———————————————————————-
1：配置web接口
假设你已经运行了apache，如果没有，请参考：

http://localhost/upload/blog.php?do-showone-tid-18.html

vi /usr/local/apache2/conf/httpd.conf
添加如下内容：
引用
ScriptAlias /nagios/cgi-bin /usr/local/nagios/sbin
Options ExecCGI
AllowOverride None
Order allow,deny
Allow from all
AuthName “Nagios Access”
AuthType Basic
AuthUserFile /usr/local/nagios/etc/htpasswd.users
Require valid-user

Alias /nagios /usr/local/nagios/share
Options None
AllowOverride None
Order allow,deny
Allow from all
AuthName “Nagios Access”
AuthType Basic
AuthUserFile /usr/local/nagios/etc/htpasswd.users
Require valid-user

修改完毕，保存文件，并重启apache：
/usr/local/apahce2/bin/apachectl restart

2：配置apache的BASIC认证：
生成认证密码：
/usr/local/apache2/bin/htpasswd –c /usr/local/nagios/etc/htpasswd.users nagios nagios
apache接口配置完成。

开始配置nagios：
cd /usr/local/nagios/etc/
在/usr/local/nagios/etc下是nagios的配置模板文件-sample,把.cfg-sample文件全部拷贝成.cfg
例如:cp nagios.cfg-sample nagios.cfg
全部拷贝完成即可.

vi minimal.cfg
注释所有command：
注释的方法是在每一个定义语句前面添加”#“
修改cgi.cfg
修改use_authentication=1为use_authentication=0,即不用验证.不然有一些页面不会显示。

现在检查配置文件是否有语法错误：
/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
如果正确，会显示以下结果：
Total Warnings: 0
Total Errors: 0
否则，需要根据提示进行修改配置文件。

配置文件等会再弄。现在启动nagios
/usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg

为了使nagios异常中断，我们使用daemontools启动：
安装daemontool：
mkdir -p /package
chmod 1755 /package
cd /package
fetch http://cr.yp.to/daemontools/daemontools-0.76.tar.gz
cd admin/daemontools-0.76/
package/install
检查svscan进程是否启动：
ps aux | grep svscan
root 376 0.0 0.0 1636 0 con- IW – 0:00.00 /bin/sh /command/svscanboot
root 411 0.0 0.0 1224 208 con- S 8Jul06 0:42.50 svscan /service

ok，启动正常了。
cd /service
mkdir nagios
chmod 1755 nagios
touch ./run
chmod 755 ./run
vi run
PATH=/usr/local/bin:/usr/bin:/bin
export PATH

exec env – PATH=$PATH \
/usr/local/nagios/bin/nagios /usr/local/nagios/etc/nagios.cfg

mkdir log
cd log
touch ./run
chmod 755 ./run
vi ./run
#!/bin/sh
exec setuidgid logadmin multilog t s1000000 n100 ./main

mkdir main
chmod 777 main
chown nagios.nagios main
touch status
chown nagios.nagios status

svc -u /service/nagios/
svstat /service/nagios/
root@## ps auxww | grep nagios
root 23276 0.0 0.1 1176 488 ?? I 5:00PM 0:01.71 supervise nagios
nagios 34251 0.0 0.3 2316 1552 ?? S 6:06PM 0:00.10 /usr/local/nagios/bin/nagios /usr/local/nagios/etc/nagios.cfg
root@##

ok，现在把nagios服务做成自动启动的服务了。
通过svc命令可以启动或者停止服务。
———————————————————————————
svc opts services
opts is a series of getopt-style options. services consists of any number of arguments, each argument naming a directory used by supervise.

-u: Up. If the service is not running, start it. If the service stops, restart it.
-d: Down. If the service is running, send it a TERM signal and then a CONT signal. After it stops, do not restart it.
-o: Once. If the service is not running, start it. Do not restart it if it stops.
-p: Pause. Send the service a STOP signal.
-c: Continue. Send the service a CONT signal.
-h: Hangup. Send the service a HUP signal.
-a: Alarm. Send the service an ALRM signal.
-i: Interrupt. Send the service an INT signal.
-t: Terminate. Send the service a TERM signal.
-k: Kill. Send the service a KILL signal.
-x: Exit. supervise will exit as soon as the service is down. If you use this option on a stable system, you’re doing something wrong; supervise is designed to run forever.
———————————————————————————
比如：
停止nagios－－svc -d /service/nagios/
重启nagios－－svc -t /service/nagios/
启动nagios－－svc -u /service/nagios/

当然，你也可以使用inited的方式进行：
/usr/local/etc/rc.d/nagios start/stop

好了，反正daemontools很强大，以后慢慢熟悉，转入正题。
现在打开网页：http://localhost/nagios/
一定会让你大吃一惊，呵呵，我的服务器和服务状态都清楚的看到了。
现在我们的nagios中只有一个，那就是它自己，localhost，呵呵，等会我们添加别的主机和主机服务，ok，我们认识一下nagios的庐山真面目：

配置nagios：

1）为主机添加服务
2）添加主机并添加服务
3）停止一个服务
4）删除一台主机和服务
5）查看所有主机的故障
6）查看一台特定的主机状态
7）改变报警的时间间隔
8）改变发现故障的重试次数
9）如何在nagios中使用外部命令

1）为主机添加一个服务
为localhost主机添加qmail服务的监控，方法如下：
vi minimal.cfg
define service{
use generic-service ; Name of service template to use
host_name localhost
service_description qmail_smtp
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_smtp!20%!10%!/
}

可以直接拷贝原有的进行修改，我这个就是拷贝的原有的check_local_disk进行的。
修改host_name，service_description，check_command等

define service{
use generic-service ; Name of service template to use
host_name localhost
service_description qmail_pop3
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_pop!20%!10%!/
}
照猫画虎的进行修改，然后去修改：
vi checkcommands.cfg
#’check_qmail’ command definition
define command{
command_name check_qmail
command_line $USER1$/check_smtp -H 127.0.0.1
}
define command{
command_name check_pop3
command_line $USER1$/check_pop -H 127.0.0.1
}
保存，然后检查配置文件：
/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
如果没有错误会显示：
Total Warnings: 0
Total Errors: 0
如果有错误，请根据提示进行错误的修正。
重启nagios
svc -d /service/nagios/ && svc -u /service/nagios/
通过web页面检查nagios的结果：

http://10.5.1.153/nagios/

点击“Service Detail”
会出现：

2）添加主机并添加服务
我们会监控这台主机的负载、磁盘等一些没有通过端口方式启动的服务器状态，以及它的服务，比如：apache、mysql、qmail和ntp等等吧。那么没有端口的nagios直接能监控到吗？答案是不行。所以我们必须在两台主机上安装nrpe，nrpe可以启动5666端口，把检测的信息源源不断的传给监控中心的主机。
ok，我们把apache、mysql、qmail和ntp先加上，这回我们把监控的主机和服务新建一个文件：
cd /usr/local/nagios/etc/
touch 10_5_1_156.cfg
vi nagios.cfg
cfg_file=/usr/local/nagios/etc/10_5_1_156.cfg

vi 10_5_1_156.cfg
定义一个主机：
define host{
use generic-host ; Name of host template to use
host_name test_nrpe
alias client
address 10.5.1.156
check_command check-host-alive
max_check_attempts 1
check_period 24×7
notification_interval 120
notification_period 24×7
notification_options d,r
contact_groups admins
}

定义主机需要检查的服务：
define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description PING
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_ping!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description apache
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_http!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description mysql
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_mysql!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description ntp
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_ntp!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description qmail_smtp
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_smtp!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description qmail_pop3
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_pop!100.0,20%!500.0,60%
}
现在我们象上次一样把
服务也定义完了：

此时是不是多了一个主机和它下面的服务呢?那是肯定的，添加主机和服务可能出现的问题有如下情况：
1：配置参数出现问题，如果你没有检查配置就启动nagios，可能会启动成功，但是显示会不正常；
解决方法：调整配置参数
2：Connection refused
当出现这个问题的时候，我开始以为是ssh的无密码登录没有成功，但是其实我的服务器没有启动该服务造成的，启动服务即可。

但是这些是有端口的服务，没有使用端口的状态任何检测？
使用nrpe，ok，我们现在在服务器上安装nrpe：
一、远程主机的配置
1、安装nrpe与配置
fetch http://ufpr.dl.sourceforge.net/sourceforge/nagios/nrpe-2.5.2.tar.gz
tar zxvf nrpe-2.5.2.tar.gz
cd nrpe-2.5.2
./configure –enable-ssl –enable-command-args
make all
mkdir -p /usr/local/nagios/etc
mkdir /usr/local/nagios/bin
mkdir /usr/local/nagios/libexec
pw addgroup nagios
pw useradd nagios -g nagios -d /usr/local/nagios/ -s /sbin/nologin
chown -R nagios:nagios /usr/local/nagios
cp ./sample-config/nrpe.cfg /usr/local/nagios/etc
cp src/nrpe /usr/local/nagios/bin
2、启动nrpe，端口为5666
/usr/local/nagios/bin/nrpe -c /usr/local/nagios/etc/nrpe.cfg -d
netstat -ant | grep 5666
tcp4 0 0 *.5666 *.* LISTEN

二、监控服务器上的配置
1、安装nrpe(主要是使用check_nrpe模块)
fetch http://ufpr.dl.sourceforge.net/sourceforge/nagios/nrpe-2.5.2.tar.gz
tar zxvf nrpe-2.5.2.tar.gz
cd nrpe-2.5.2
./configure –enable-ssl –enable-command-args
make all
cp src/check_nrpe /usr/local/nagios/libexec
2、nagios文件的配置
vi checkcommands.cfg
定义check_nrpe命令
# ‘check_nrep’ command definition
define command{
command_name check_nrpe
command_line /usr/local/nagios/libexec/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
}
三、上面我们已经配置了一部分参数，下面是配置的最终结果：
define host{
use generic-host ; Name of host template to use
host_name test_nrpe
alias client
address 10.5.1.156
check_command check-host-alive
max_check_attempts 1
check_period 24×7
notification_interval 120
notification_period 24×7
notification_options d,r
contact_groups admins
}

# ‘check_load’ command definition
define command{
command_name check_load
command_line $USER1$/check_load -w $ARG1$ -c $ARG2$
}

# ‘check_load’ command definition
define command{
command_name check_disk
command_line $USER1$/check_disk -w $ARG1$ -c $ARG2$
}
define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description PING
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_ping!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description apache
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_http!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description mysql
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_mysql!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description ntp
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_ntp!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description qmail_smtp
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_smtp!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description qmail_pop3
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_pop!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description test_load
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_load!100.0,20%!500.0,60%
}

define service{
use generic-service ; Name of service template to use
host_name test_nrpe
service_description test_disk
is_volatile 0
check_period 24×7
max_check_attempts 1
normal_check_interval 1
retry_check_interval 1
contact_groups admins
notification_options w,u,c,r
notification_interval 960
notification_period 24×7
check_command check_disk!100.0,20%!500.0,60%
}

四、检查配置参数并重启nagios

9）如何在nagios中使用外部命令
vi /usr/local/nagios/etc/nagios.cfg
check_external_commands=1

mkdir /usr/local/nagios/var/rw
chown nagios.nagcmd /usr/local/nagios/var/rw
chmod u+rw /usr/local/nagios/var/rw
chmod g+rw /usr/local/nagios/var/rw
chmod g+s /usr/local/nagios/var/rw

svc -t /service/nagios/
/usr/local/apache2/bin/apachectl restart