10.Nagios如何监控Linux机器


NRPE总共由两部分组成:
(1).check_nrpe插件,运行在监控主机上。
(2).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：
1).nagios会运行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.

11.Nagios的配置文件
＃ 控制cgi访问的配置文件
cgi.cfg
＃ Nagios主配置文件
nagios.cfg
＃ resource.cfg定义了一些变量，以便被其他文件引用，如$USER1$
resource.cfg
# objects是一个目录，用于定义Nagios对象
objects
# servers是自己创建的一个目录，Nagios可以加载一个目录下面的所有配置文件（需要在nagios.cfg中配置）
servers

./objects:
＃ 命令定义配置文件，里面定义的命令可以被其他文件引用
commands.cfg
＃ 联系人和联系人组配置文件
contacts.cfg
＃ 监控本地机器的配置文件
localhost.cfg
＃ 监控打印机的一个事例配置文件（默认未启用）
printer.cfg
＃ 监控路由器的一个事例配置文件（默认未启用）
switch.cfg
＃ 模板配置文件，在此可以定义模板，在其他文件中引用
templates.cfg
＃ 定义监控时间段的配置文件
timeperiods.cfg
＃ 监控Windows的一个事例配置文件（默认未启用）
windows.cfg

./servers:
＃ 自己创建的主机群组配置文件
hostgroup.cfg
＃ 自己创建的监控远程Linux主机的配置文件
wiki-l-11.cfg

配置文件是怎样引用的？

用nagios主要是监控一台主机的各种信息,包括本机资源以及对外的服务等等.这些在nagios里面都是被定义为一个个的项目(nagios称之为服 务,为了与主机提供的服务相区别,我这里用项目这个词),而实现每个监控项目,则需要通过commands.cfg文件中定义的命令。
为了不必重复定义一些项目，Nagios引入了一个模板配置文件（templates.cfg），将一些共性的属性定义成模板，以便于多次引用。
我们现在有一个监控项目是监控一台机器的web服务是否正常, 我们需要哪些元素呢?最重要的有下面三点:首先是监控哪台机器,然后是这个监控要用什么命令实现,最后就是出了问题的时候要通知哪个联系人。
我们首先应该在commands.cfg中定义监控远程服务和资源的命令，以及如何发送邮件的命令。大部分监控远程服务和资源的命令的命令通过/usr/local/nagios/libexec下的脚本实现，如ping命令为check_ping。
/usr/local/nagios/libexec下的脚本命令的使用发法可以通过-h参数查看，如：
-----------------------------------------------------------------------------------------
[root@tech ~]# /usr/local/nagios/libexec/check_ping -h
check_ping v1991 (nagios-plugins 1.4.13)
Copyright (c) 1999 Ethan Galstad <nagios@nagios.org>
Copyright (c) 2000-2007 Nagios Plugin Development Team
    <nagiosplug-devel@lists.sourceforge.net>

Use ping to check connection statistics for a remote host.

Usage:check_ping -H <host_address> -w <wrta>,<wpl>% -c <crta>,<cpl>%
 [-p packets] [-t timeout] [-4|-6]

Options:
 -h, --help
    Print detailed help screen
 -V, --version
    Print version information
 -4, --use-ipv4
    Use IPv4 connection
 -6, --use-ipv6
    Use IPv6 connection
 -H, --hostname=HOST
    host to ping
 -w, --warning=THRESHOLD
    warning threshold pair
 -c, --critical=THRESHOLD
    critical threshold pair
 -p, --packets=INTEGER
    number of ICMP ECHO packets to send (Default: 5)
 -L, --link
    show HTML in the plugin output (obsoleted by urlize)
 -t, --timeout=INTEGER
    Seconds before connection times out (default: 10)
-----------------------------------------------------------------------------------------
然后我们在contacts.cfg文件中定义联系人和联系人组，在timeperiods.cfg中定义监控时间段。最后我们在服务器监控配置文件中引用前面定义的元素来监控服务器状态。

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
下面引用配置文件中部分配置做说明：
vi /usr/local/nagios/etc/resource.cfg
＃ 定义$USER1$变量，设置插件路径
$USER1$=/usr/local/nagios/libexec

vi /usr/local/nagios/etc/objects/commands.cfg
＃ 定义check-host-alive命令
define command{
        command_name    check-host-alive  ＃ 命令名称
        command_line    $USER1$/check_ping -H $HOSTADDRESS$ -w 3000.0,80% -c 5000.0,100% -p 5
        }
＃ 上面的$USER1$和$HOSTADDRESS$引用自已定义的配置文件。变量不需现定义才能被引用。
########################################################################
#
# 2008.11.18 add by Stone
# NRPE COMMAND
# 自己定义check_nrpe命令，此命令后接必需接一个参数，用于告诉远程服务器上的NRPE daemon需要监控的内容，如check_swap参数为监控远程机器的交换分区。
########################################################################
# 'check_nrpe ' command definition
define command{
        command_name check_nrpe
        command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
        }


vi /usr/local/nagios/etc/objects/contacts.cfg
＃ 定义联系人
define contact{
        contact_name                    nagiosadmin             ; Short name of user
        use                             generic-contact         ; Inherit default values from generic-contact template (defined above)
        alias                           Nagios Admin            ; Full name of user

        email                           test@gmaile.com         ; <<***** CHANGE THIS TO YOUR EMAIL ADDRESS ******
        }
＃ 上面的generic-contact在templates.cfg中定义。
＃ 定义联系人组
define contactgroup{
        contactgroup_name       admins
        alias                   Nagios Administrators
        members                 nagiosadmin   ＃在此可以加入多个联系人，中间用逗号隔开
        }

vi /usr/local/nagios/etc/objects/timeperiods.cfg
＃ 定义监控的时间段
define timeperiod{
        timeperiod_name 24x7   ＃监控所有时间段（7＊24小时）
        alias           24 Hours A Day, 7 Days A Week
        sunday          00:00-24:00
        monday          00:00-24:00
        tuesday         00:00-24:00
        wednesday       00:00-24:00
        thursday        00:00-24:00
        friday          00:00-24:00
        saturday        00:00-24:00
        }

vi /usr/local/nagios/etc/objects/templates.cfg
＃ 定义generic-contact联系人模板，并非真正的联系人，真正的联系人在contacts.cfg中定义
define contact{
        name                            generic-contact         ; The name of this contact template
        service_notification_period     24x7                    ; service notifications can be sent anytime
        host_notification_period        24x7                    ; host notifications can be sent anytime
        service_notification_options    w,u,c,r,f,s             ; send notifications for all service states, flapping events, and scheduled downtime events
        host_notification_options       d,u,r,f,s               ; send notifications for all host states, flapping events, and scheduled downtime events
        service_notification_commands   notify-service-by-email ; send service notifications via email
        host_notification_commands      notify-host-by-email    ; send host notifications via email
        register                        0                       ; DONT REGISTER THIS DEFINITION - ITS NOT A REAL CONTACT, JUST A TEMPLATE!
        }
------------------------------------------------------------------------------------------------------------------
service_notification_period     24x7
服务出了状况通知的时间段,这个时间段就是上面在timeperiods.cfg中定义的.
host_notification_period        24x7
主机出了状况通知的时间段, 这个时间段就是上面在timeperiods.cfg中定义的
service_notification_options    w,u,c,r
当服务出现w—报警(warning),u—未知(unkown),c—严重(critical),或者r—从异常情况恢复正常,在这四种情况下通知联系人.
host_notification_options       d,u,r
当主机出现d­­­­—当机(down),u—返回不可达(unreachable),r—从异常情况恢复正常,在这3种情况下通知联系人
service_notification_commands   notify-service-by-email
服务出问题通知采用的命令notify-service-by-email,这个命令是在commands.cfg中定义的,作用是给联系人发邮件.
host_notification_commands      notify-host-by-email
同上,主机出问题时采用的也是发邮件的方式通知联系人
------------------------------------------------------------------------------------------------------------------

＃ 定义generic-host主机模板
define host{
        name                            generic-host    ; The name of this host template
        notifications_enabled           1               ; Host notifications are enabled
        event_handler_enabled           1               ; Host event handler is enabled
        flap_detection_enabled          1               ; Flap detection is enabled
        failure_prediction_enabled      1               ; Failure prediction is enabled
        process_perf_data               1               ; Process performance data
        retain_status_information       1               ; Retain status information across program restarts
        retain_nonstatus_information    1               ; Retain non-status information across program restarts
        notification_period             24x7            ; Send host notifications at any time
        register                        0               ; DONT REGISTER THIS DEFINITION - ITS NOT A REAL HOST, JUST A TEMPLATE!
        }

＃ 定义Linux主机模板
define host{
        name                            linux-server    ; The name of this host template
        use                             generic-host    ; This template inherits other values from the generic-host template
        check_period                    24x7            ; By default, Linux hosts are checked round the clock
        check_interval                  5               ; Actively check the host every 5 minutes
        retry_interval                  1               ; Schedule host check retries at 1 minute intervals
        max_check_attempts              10              ; Check each Linux host 10 times (max)
        check_command                   check-host-alive ; Default command to check Linux hosts
        notification_period             workhours       ; Linux admins hate to be woken up, so we only notify during the day
                                                        ; Note that the notification_period variable is being overridden from
                                                        ; the value that is inherited from the generic-host template!
        notification_interval           120             ; Resend notifications every 2 hours
        notification_options            d,u,r           ; Only send notifications for specific host states
        contact_groups                  admins          ; Notifications get sent to the admins by default
        register                        0               ; DONT REGISTER THIS DEFINITION - ITS NOT A REAL HOST, JUST A TEMPLATE!
        }

＃ 在nagios.cfg配置文件中开启对/usr/local/nagios/etc/servers/中配置文件的引用。
cfg_dir=/usr/local/nagios/etc/servers

＃ 远程Linux主机监控文件，如果监控多台主机只需简单复制修改即可。
＃我们应该牢记wiki-l-11.cfg用到的命令在commands.cfg中定义，在commands.cfg中定义的命令用到/usr/local/nagios/libexec下的插件（命令）。
vi /usr/local/nagios/etc/servers/wiki-l-11.cfg
＃ 定义主机
define host{
        use                     linux-server            ; Name of host template to use
                                                        ; This host definition will inherit all variables that are defined
                                                        ; in (or inherited by) the linux-server host template definition.
        host_name               wiki
        alias                   Docs
        address                 192.168.0.11
        }
＃ 定义Ping远程Linux主机
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             PING
        check_command                   check_ping!100.0,20%!500.0,60%   ;check_ping命令在commands.cfg中定义，后跟两个参数，命令及参数间用!分割。
        }
＃检查远程Linux主机根分区使用情况，check_nrpe命令必须在/usr/local/nagios/etc/objects/commands.cfg中定义（默认未定义）
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             Root Partition
        check_command                   check_nrpe!check_disk_root
        }
＃ 检查远程Linux主机的登录人数
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             Current Users
        check_command                   check_nrpe!check_users
        }
＃ 检查远程Linux的主机的负载
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             Current Load
        check_command                   check_nrpe!check_load
        }
＃ 检查远程Linux主机swap分区使用情况
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             Swap Usage
        check_command                   check_nrpe!check_swap
        }
＃ 检查远程Linux主机的SSH服务
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             SSH
        check_command                   check_ssh
        notifications_enabled           0
        }
＃ 检查远程Linux主机的HTTP服务
define service{
        use                             generic-service         ; Name of service template to use
        host_name                       wiki
        service_description             HTTP
        check_command                   check_http
        notifications_enabled           0
        }

vi /usr/local/nagios/etc/servers/hostgroup.cfg
＃ 定义主机组（localhost.cfg中有类似的主机组设置，我已将其注释掉，否则可能会有冲突）
define hostgroup{
        hostgroup_name  linux-servers ; The name of the hostgroup
        alias           Linux Servers ; Long name of the group
        members         localhost,wiki     ; Comma separated list of hosts that belong to this group
        }

#define hostgroup{
#        hostgroup_name  windows-servers ; The name of the hostgroup
#        alias           Windows Servers ; Long name of the group
#        members         print     ; Comma separated list of hosts that belong to this group
#        }
＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
＃ 完成监控主机配置文件的配置后使用下面命令检查配置文件的正确性：
/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
＃ 确定无误后重启Nagios：
service nagios restart

使用Nagios监控Windows服务器

12.Nagios使用NSClient++监控远程Windows主机

NSClient++ /install
 NSClient++ SysTray install
 NSClient++ /start
如果有防火墙，请开放相应端口。
创建监控配置文件，使用check_nt命令监控windows系统信息（此命令默认已定义）。

Ｗindows监控示例配置文件：
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[root@tech etc]# cat /usr/local/nagios/etc/servers/print-w-80.cfg
###############################################################################
# WINDOWS.CFG - SAMPLE CONFIG FILE FOR MONITORING A WINDOWS MACHINE
#
# Last Modified: 06-13-2007
#
# NOTES: This config file assumes that you are using the sample configuration
#     files that get installed with the Nagios quickstart guide.
#
###############################################################################



###############################################################################
###############################################################################
#
# HOST DEFINITIONS
#
###############################################################################
###############################################################################

# Define a host for the Windows machine we'll be monitoring
# Change the host_name, alias, and address to fit your situation

define host{
    use        windows-server    ; Inherit default values from a template
    host_name    print80        ; The name we're giving to this host
    alias        Print80        ; A longer name associated with the host
    address        192.168.0.80    ; IP address of the host
    }

###############################################################################
###############################################################################
#
# HOST GROUP DEFINITIONS
# 主机组在/usr/local/nagios/etc/servers/hostgroup.cfg中单独配置
###############################################################################
###############################################################################


# Define a hostgroup for Windows machines
# All hosts that use the windows-server template will automatically be a member of this group

#define hostgroup{
#    hostgroup_name    windows-servers    ; The name of the hostgroup
#    alias        Windows Servers    ; Long name of the group
#    }


###############################################################################
###############################################################################
#
# SERVICE DEFINITIONS
#
###############################################################################
###############################################################################


# Create a service for monitoring the version of NSCLient++ that is installed
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    NSClient++ Version
    check_command        check_nt!CLIENTVERSION
    }

# Create a service for monitoring the uptime of the server
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    Uptime
    check_command        check_nt!UPTIME
    }

# Create a service for monitoring CPU load
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    CPU Load
    check_command        check_nt!CPULOAD!-l 5,80,90
    }

# Create a service for monitoring
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    Memory Usage
    check_command        check_nt!MEMUSE!-w 80 -c 90
    }

# Create a service for monitoring C:\ disk usage
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    C_Drive_Space
    check_command        check_nt!USEDDISKSPACE!-l c -w 80 -c 90
    }

# Create a service for monitoring the W3SVC service
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    W3SVC
    check_command        check_nt!SERVICESTATE!-d SHOWALL -l W3SVC
    }

# Create a service for monitoring the Explorer.exe process
# Change the host_name to match the name of the host you defined above

define service{
    use            generic-service
    host_name        print80
    service_description    Explorer
    check_command        check_nt!PROCSTATE!-d SHOWALL -l Explorer.exe
    }

＃主机组配置文件
[root@tech etc]# cat /usr/local/nagios/etc/servers/hostgroup.cfg
define hostgroup{
        hostgroup_name  linux-servers ; The name of the hostgroup
        alias           Linux Servers ; Long name of the group
        members         localhost,wiki     ; Comma separated list of hosts that belong to this group
        }

define hostgroup{
        hostgroup_name  windows-servers ; The name of the hostgroup
        alias           Windows Servers ; Long name of the group
        members         print80     ; Comma separated list of hosts that belong to this group
        }
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

使用NDOUtils将Nagios监控信息存入数据库

1.NDOUtils安装需求：
Nagios正确安装运行，版本>=2.0安装目录：/usr/local/nagios
MySQL正确安装并运行，我用的是二进制安装包，安装目录：/usr/local/mysql

2.安装
下载安装包：http://www.nagios.org/download/
#　确认DBD-mysql包安装，如没有安装，请先安装。
# 如果DBI包没安装DBD-mysql前需要先安装DBI包
tar xzvf DBI-1.605.tar.gz
cd DBI-1.605
perl Makefile.PL
make
make install

tar xzvf DBD-mysql-3.0008.tar.gz
cd DBD-mysql-3.0008
unset LANG
perl Makefile.PL --libs="-L/usr/local/mysql/lib/mysql -lmysqlclient -L/usr/lib -lz " --cflags="-I/usr/local/mysql/include"  --testhost=127.0.0.1 --mysql_config=/usr/local/mysql/bin/mysql_config --testuser=root --testpassword=baihe.com
make
make install

#　做好MySQL库文件lib和include文件的连接（这点很重要）。
ln -s /usr/local/mysql/include/* /usr/include/
mkdir /usr/include/mysql
ln -s /usr/local/mysql/include/* /usr/include/mysql/
ln -s /usr/local/mysql/lib/* /usr/lib/
mkdir /usr/lib/mysql
ln -s /usr/local/mysql/lib/* /usr/lib/mysql

tar xzvf ndoutils-1.4b7.tar.gz
cd ndoutils-1.4b7
./configure --enable-mysql
#　执行完成后，注意向上看看打印出的信息，看看是否找到了MySQL的库文件和include文件。
make
cd src/
#　我的Nagios是3.0.5，所以拷贝的是ndomod-3x.o、ndo2db-3x，如果你的是2.X.x请拷贝ndomod-2x.o、ndo2db-2x
cp ndomod-3x.o ndo2db-3x log2ndo file2sock /usr/local/nagios/bin
cd ../db
#　创建数据库，使用root用户，密码是baihe.com
mysqladmin -u root -pbaihe.com create nagios
./installdb -u root -p baihe.com -d nagios
#　拷贝配置文件
cd ../config
cp ndo* /usr/local/nagios/etc/
#　修改/usr/local/nagios/etc/ndo2db.cfg文件的数据库信息。
vi /usr/local/nagios/etc/ndo2db.cfg
vi nagios.cfg
#　复制下面内容粘贴到/usr/local/nagios/etc/nagios.cfg配置文件的#broker_module＝...下面。
# Uncomment the line below if you're running Nagios 3.x
broker_module=/usr/local/nagios/bin/ndomod-3x.o config_file=/usr/local/nagios/etc/ndomod.cfg
#　修改/usr/local/nagios/etc/nagios.cfg配置文件下面参数的值为-1（一般默认如此）。
event_broker_options=-1

# 启动ndo2db
/usr/local/nagios/bin/ndo2db-3x -c /usr/local/nagios/etc/ndo2db.cfg
# 查看系统日志是否有错误信息：
tail -30 /var/log/messages
Nov 27 14:09:26 tech nagios: ndomod: NDOMOD 1.4b7 (10-31-2007) Copyright (c) 2005-2007 Ethan Galstad (nagios@nagios.org)
Nov 27 14:09:26 tech nagios: ndomod: Successfully connected to data sink.  0 queued items to flush.
Nov 27 14:09:26 tech nagios: Event broker module '/usr/local/nagios/bin/ndomod-3x.o' initialized successfully.
Nov 27 14:09:26 tech nagios: Finished daemonizing... (New PID=18848)
# 重启Nagios
service nagios restart
# 查看Nagios日志，看是否正常启动。
tail -20 /usr/local/nagios/var/nagios.log
[1227766166] ndomod: NDOMOD 1.4b7 (10-31-2007) Copyright (c) 2005-2007 Ethan Galstad (nagios@nagios.org)
[1227766166] ndomod: Successfully connected to data sink.  0 queued items to flush.
[1227766166] Event broker module '/usr/local/nagios/bin/ndomod-3x.o' initialized successfully.
[1227766166] Finished daemonizing... (New PID=18848)

3.如何用NDOUtils将多个Nagios实例的性能数据写入一个数据库？