Wise Turtles

Install Nagios 4 on Ubuntu/Debian


Tags Ubuntu Debian Monitor Management By Zhang Wanming On 2015-05-23

Ucloud后台监控系统功能很简单，最近发现之前设置过的监控项也无法正常显示，更不能编辑了。 虽然，马上就要将系统迁移到公司自己大家的云平台，但，最近Ucloud服务器压力很大，周末抽空先将Nagios搭建起来，让自己能及时收到报警。

我们Ucloud服务器都用的Debian 7 (wheezy)，源里只有nagios3，所以，自己编译、安装Nagios 4。

监控主机安装Nagios

安装需要的软件包

$ sudo apt-get install build-essential libgd2-xpm-dev openssl libssl-dev apache2 php5 libapache2-mod-php5 apache2-utils postfix

创建用户、组

$ sudo useradd nagios
$ sudo groupadd nagcmd
$ sudo usermod -a -G nagcmd nagios

安装nagios 4

$ cd /data/software
$ wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-4.0.8.tar.gz
$ tar zxf nagios-4.0.8.tar.gz
$ cd nagios-4.0.8
$ ./configure --with-nagios-group=nagios --with-command-group=nagcmd --with-mail=$(which sendmail)
$ sudo make all
$ sudo make install && make install-commandmode && make install-init && make install-config
$ sudo ln -s /etc/init.d/nagios /etc/rcS.d/S99nagios # 开机自启动
$ sudo service nagios restart

配置apache2

$ sudo /usr/bin/install -c -m 644 sample-config/httpd.conf /etc/apache2/sites-available/nagios.conf
$ sudo ln -s /etc/apache2/sites-available/nagios.conf /etc/apache2/sites-enabled/
$ sudo a2enmod rewrite
$ sudo a2enmod cgi
$ sudo htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
$ sudo service apache2 restart

浏览器访问 http://监控主机IP/nagios 查看监控情况, 登录用户名、密码就是 htpasswd 设置的。 nagios 4将被安装到 /usr/local/nagios 目录，该目录下的 etc 是配置文件夹。

安装nagios-plugins-2.0.3

$ cd /data/software
$ wget https://nagios-plugins.org/download/nagios-plugins-2.0.3.tar.gz
$ tar zxf nagios-plugins-2.0.3.tar.gz
$ cd nagios-plugins-2.0.3
$ ./configure --with-nagios-user=nagios --with-nagios-group=nagios --with-openssl
$ make all && make install

nagios-plugins 命令安装在 /usr/local/nagios/libexec 目录。

安装nagios-nrpe-2.15

$ cd /data/software
$ wget -O nrpe-2.15.tar.gz "http://downloads.sourceforge.net/project/nagios/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz?r=http%3A%2F%2Fsourceforge.net%2Fprojects%2Fnagios%2Ffiles%2Fnrpe-2.x%2Fnrpe-2.15%2F&ts=1432369927&use_mirror=liquidtelecom"
$ tar zxf nrpe-2.15.tar.gz
$ cd nrpe-2.15
$ ./configure --with-nagios-user=nagios --with-nagios-group=nagios --with-ssl=/usr/bin/openssl --with-ssl-lib=/usr/lib/x86_64-linux-gnu 
$ make all
$ find -iname 'check_nrpe'
$ sudo /usr/bin/install -c -m 755 ./src/check_nrpe /usr/local/nagios/libexec/

测试是否可以工作:

$ /usr/local/nagios/libexec/check_nrpe -H 10.4.2.2 # 该IP是被监控主机的IP
NRPE v2.13

被监控主机安装Nagios NRPE

安装nagios-plugins, nagios-nrpe-server

$ sudo apt-get install nagios-plugins nagios-nrpe-server

配置nagios-nrpe-server，允许监控主机连接该被监控主机。

$ sudo vim /etc/nagios/nrpe.cfg
$ 将 监控主机IP 填入 allowed_hosts 字段，如: allowed_hosts=127.0.0.1,10.4.22.22
$ sudo service nagios-nrpe-server restart

配置

配置监控主机

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

$ diff -u nagios.cfg.back nagios.cfg
--- nagios.cfg.back2015-05-23 11:07:51.436491931 +0800
+++ nagios.cfg2015-05-23 22:08:09.872618927 +0800
@@ -30,6 +30,9 @@
cfg_file=/usr/local/nagios/etc/objects/contacts.cfg
cfg_file=/usr/local/nagios/etc/objects/timeperiods.cfg
cfg_file=/usr/local/nagios/etc/objects/templates.cfg
+cfg_file=/usr/local/nagios/etc/objects/hosts.cfg
+cfg_file=/usr/local/nagios/etc/objects/groups.cfg
+cfg_file=/usr/local/nagios/etc/objects/services.cfg

# Definitions for monitoring the local (Linux) host
cfg_file=/usr/local/nagios/etc/objects/localhost.cfg
@@ -1174,7 +1177,7 @@
# using the $ADMINEMAIL$ and $ADMINPAGER$ macros in your notification
# commands.

-admin_email=nagios@localhost
+admin_email=your-emai-address
admin_pager=pagenagios@localhost

/usr/local/nagios/etc/objects/hosts.cfg

$ # Define a host for the local machine
##############
# appstore01 #
##############
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                       appstore01
    alias                           appstore01 on ucloud
    address                         10.4.2.2
    }

##############
# appstore02 #
##############
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                       appstore02
    alias                           appstore02 on ucloud
    address                         10.4.2.22
    }

/usr/local/nagios/etc/objects/groups.cfg

# Define an optional hostgroup for Linux machines
define hostgroup{
    hostgroup_name  appstore-group ; The name of the hostgroup
    alias           appstore server group ; Long name of the group
    members         appstore01,appstore02     ; Comma separated list of hosts that belong to this group
    }

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

$ diff -u objects/commands.cfg.back objects/commands.cfg
+########################
+# add by zhang wanming #
+########################
+# 'check_mysql' command definition
+define command{
+   command_name    check_mysql
+   command_line    $USER1$/check_mysql -H $HOSTADDRESS$ -u $ARG1$ -p $ARG2$ -d $ARG3$ -P 3306
+   }

+# 'check_http_with_url_port' command definition
+define command{
+        command_name    check_http_with_url_port
+        command_line    $USER1$/check_http -I $HOSTADDRESS$ -u $ARG1$ -p $ARG2$
+        }
+
+# 'check_nrpe' command definition
+define command{
+        command_name check_nrpe
+        command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
+        }
+
+# 'check_memcached' command definition
+define command{
+        command_name check_memcached
+        command_line $USER1$/check_tcp -H $HOSTADDRESS$ -p 11211 -t 5 -E -s 'stats\r\nquit\r\n' -e 'uptime' -M crit
+        }

/etc/local/nagios/etc/objects/services.cfg

$ cat objects/services.cfg 
define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             PING
        check_command                   check_ping!100.0,20%!500.0,60%
}

define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             SSH
        check_command                   check_ssh!-p 1122
}

#################
# HTTP services #
#################
define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             Nginx
        check_command                   check_http
}

define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             check http tdnaceweb
        check_command                   check_nrpe!check_http_tdanceweb
}

define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             check http appstore
        check_command                   check_nrpe!check_http_appstore
}

define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             check http launcher
        check_command                   check_nrpe!check_http_launcher
}

#########
# Redis #
#########
define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             Redis
        check_command                   check_nrpe!check_redis
}

#############
# Memcached #
#############
define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             Memcached
        check_command                   check_nrpe!check_memcached
}

#########
# MySQL #
#########
define service {
        use                             generic-service
        host_name                       appstore01
        service_description             MySQL
        check_command                   check_nrpe!check_mysql
}

################
# disk/partion #
################
define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             check root disk
        check_command                   check_nrpe!check_disk_root
}

define service {
        use                             generic-service
        hostgroup_name                  appstore-group
        service_description             check root data
        check_command                   check_nrpe!check_disk_data
}

配置被监控主机

$ cat /etc/nagios/nrpe_local.cfg 
######################################
# Do any local nrpe configuration here
######################################
command[check_disk_root]=/usr/lib/nagios/plugins/check_disk -w 25% -c 10% -p /
command[check_disk_data]=/usr/lib/nagios/plugins/check_disk -w 25% -c 10% -p /data
command[check_redis]=/usr/lib/nagios/plugins/check_tcp -H localhost -p 6379 -t 5 -E -s 'info\r\n' -q 'quit\r\n' -e 'uptime_in_days' -M crit
command[check_memcached]=/usr/lib/nagios/plugins/check_tcp -H localhost -p 11211 -t 5 -E -s 'stats\r\nquit\r\n' -e 'uptime' -M crit
command[check_mysql]=/usr/lib/nagios/plugins/check_mysql -H localhost -u user -p passwd -d your-database
command[check_http_tdanceweb]=/usr/lib/nagios/plugins/check_http -H localhost -p 6688 -t 3
command[check_http_appstore]=/usr/lib/nagios/plugins/check_http -H localhost -p 8888 -t 3 -u /m3/subjects
command[check_http_launcher]=/usr/lib/nagios/plugins/check_http -H localhost -p 9999 -t 3

配置过程中碰到的问题

监控服务器上没有check_nrpe命令

如果没有安装nrpe，请下载、编译、安装，请参考 安装nagios-nrpe-2.15

CHECK_NRPE: Error - Could not complete SSL handshake.

编辑/etc/nagios/nrpe.cfg, 确定 allowed_hosts 中加入监控主机IP，多个IP以 “,” 分隔。 如: allowed_hosts=127.0.0.1,10.4.13.14

然后，重新加载 nagios-nrpe-server 配置文件，如下：

$ service nagios-nrpe-server reload

下次再学习并补充联系人及报警相关设置。

参考：

  1. https://www.digitalocean.com/community/tutorials/how-to-install-nagios-4-and-monitor-your-servers-on-ubuntu-14-04
  2. http://netkiller.github.io/monitoring/nagios/