nagios安装使用

nagios

nagios自身在ubuntu上的安装可参照http://nagios.sourceforge.net/docs/3_0/quickstart-ubuntu.html

NRPE安装参照http://blog.c1gstudio.com/archives/559 , 另在此之前安装libssl-dev

percona monitoring plugin 可参见http://www.percona.com/software/percona-monitoring-plugins/ , can integrate with nagios

其实我就是一个网络搬运工

安装

in nagios server (ubuntu 12.04):

机器A， ip 172.16.21.119

apt-get install libssl-dev openssl

dpkg -L libssl-dev #see libssl.so real path

ln -s /usr/lib/x86_64-linux-gnu/libssl.so /usr/lib/libssl.so

apt-get install apache2 libapache2-mod-php5 build-essential libgd2-xpm-dev

useradd -m -s /bin/bash nagios

passwd nagios

groupadd nagcmd

usermod -a -G nagcmd nagios

usermod -a -G nagcmd www-data

mkdir ~/downloads && cd ~/downloads

wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-3.2.3.tar.gz

wget https://www.nagios-plugins.org/download/nagios-plugins-1.5.tar.gz

tar xvf nagios-3.2.3.tar.gz

cd nagios-3.2.3

./configure –with-command-group=nagcmd

make all

make install

make install-init

make install-config

make install-commandmode

vim /usr/local/nagios/etc/objects/contacts.cfg #and change email address associated with nagiosadmin

make install-webconf

htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin #and remember the password

/etc/init.d/apache2 reload

cd ..

tar xvf nagios-plugins-1.5.tar.gz

cd nagios-plugins-1.5

./configure –with-nagios-user=nagios –with-nagios-group=nagios

make

make install

ln -s /etc/init.d/nagios /etc/rcS.d/S99nagios

/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg

/etc/init.d/nagios start

cd ..

wget http://sourceforge.net/projects/nagios/files/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz

tar xvf nrpe-2.12.tar.gz

cd nrpe-2.12

./configure –prefix=/usr/local/nagios

make all

make install-plugin

/usr/local/nagios/libexec/check_nrpe -H xxx.xxx.xxx.xxx #after nagios client run nrpe deamon, use this to check, xxx.xxx.xxx.xxx is client ip

vim /usr/local/nagios/etc/objects/commands.cfg , add:

# 'check_nrpe ' command definition
define command{
    command_name check_nrpe
    command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
    }

vim /usr/local/nagios/etc/objects/hostA.cfg , add:

define host{
    use                   generic-server ;is checkconfig error, use linux-server instead
    host_name             uts-app-2
    alias                 uts-app-2
    address               172.16.21.59
    }

define service{
    use   generic-service
    host_name  uts-app-2
    service_description load
    check_command  check_nrpe!check_load
    }

echo “cfg_file=/usr/local/nagios/etc/objects/hostA.cfg” >> /usr/local/nagios/etc/nagios.cfg

service nagios reload

see nagios web interface at http://localhost/nagios/

in nagios client(ubuntu 12.04):

机器B, ip 172.16.21.59

apt-get install libssl-dev openssl

dpkg -L libssl-dev #see libssl.so real path

ln -s /usr/lib/x86_64-linux-gnu/libssl.so /usr/lib/libssl.so

groupadd nagios

useradd -g nagios -d /usr/local/nagios -s /sbin/nologin nagios

wget https://www.nagios-plugins.org/download/nagios-plugins-1.5.tar.gz

tar xvf nagios-plugins-1.5.tar.gz

cd nagios-plugins-1.5

./configure –with-nagios-user=nagios –with-nagios-group=nagios –prefix=/usr/local/nagios –with-ping-command=”/bin/ping”

make

make install

ls /usr/local/nagios/libexec #check

cd ..

wget http://sourceforge.net/projects/nagios/files/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz

tar xvf nrpe-2.12.tar.gz

cd nrpe-2.12

./configure –prefix=/usr/local/nagios

make all

make install-plugin

make install-daemon

make install-daemon-config

chown -R nagios:nagios /usr/local/nagios

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

allowed_hosts=127.0.0.1,172.16.21.119

echo ‘nrpe:192.172.16.21.119’ >> /etc/hosts.allow

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

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

netstat -an | grep 5666 #check

echo “/usr/local/nagios/bin/nrpe -c /usr/local/nagios/etc/nrpe.cfg -d” >> /etc/rc.local #开机启动

some additions

如何修改nrpe端口
被监控机nrpe.cfg修改server_port为15666
/usr/local/nagios/libexec/check_nrpe -p 15666 -H 127.0.0.1

server_port=15666
重启nrpe

监控机commands.cfg增加-p 15666

define command{
        command_name check_nrpe
        command_line $USER1$/check_nrpe -H $HOSTADDRESS$ -p 15666 -c $ARG1$
        }
重启nagios就可以了

Connection refused or timed out
检查nrpe 端口
检查nrpe.cfg中allowed_hosts是否包含监控机ip地址
检查/etc/hosts.allow文件中监控机ip地址nrpe:192.168.1.91
检查iptables

开放5666端口

iptables -L
iptables -A RH-Firewall-1-INPUT -p tcp -m state --state NEW -m tcp --dport 5666 -j ACCEPT
#注意顺序
iptables -L
service iptables save
service iptables restart

添加更多监控项

以添加check_procs举例

B:

vim /usr/local/nagios/etc/nrpe.cfg ,add

command[check_procs]=/usr/local/nagios/libexec/check_procs -w 5:100 -c 2:1024

ps aux | grep nagios

kill -9 xxxx #xxxx is nagios pid

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

A:

vim /usr/local/nagios/etc/objects/hostA.cfg ,add

define service{
    use   generic-service
    host_name  uts-app-2
    service_description procs
    check_command  check_nrpe!check_procs
    }

service nagios reload

自定义监控

功能强大的Nagios网络监控平台让你可以为其功能增添一系列可用插件。如果你找不到可以满足自身要求的一款插件，也很容易自行编写.

Nagios插件可以用任何一门编程语言来编写，只要该编程语言在运行Nagios的平台上得到支持。Bash是用来编写Nagios插件的一门流行语言，因为它功能强大、使用简单。

借助插件进行的每一次有效的Nagios检查（Nagios check）都会生成一个数字表示的退出状态。可能的状态有：

• 0–各方面都正常，检查成功完成。
• 1–资源处于警告状态。某个地方不太妙。
• 2–资源处于临界状态。原因可能是主机宕机或服务未运行。
• 3–未知状态，这未必表明就有问题，而是表明检查没有给出一个清楚明确的状态。

插件还能输出文本消息。默认情况下，该消息显示在Nagios web界面和Nagios邮件警报信息中。尽管消息并不是硬性要求，你通常还是可以在可用插件中找到它们，因为消息告诉用户出了什么岔子，而不会迫使用户查阅说明文档。

an simple example write by shell to check nginx

vim /usr/local/nagios/libexec/check_nginx

#! /bin/bash

ECHO="/bin/echo"
GREP="/bin/egrep"
DIFF="/usr/bin/diff"
TAIL="/usr/bin/tail"
CAT="/bin/cat"
RM="/bin/rm"
CHMOD="/bin/chmod"
TOUCH="/bin/touch"

PROGNAME=`/usr/bin/basename $0`
PROGPATH=`echo $0 | sed -e 's,[\\/][^\\/][^\\/]*$,,'`
REVISION="0.1"

. $PROGPATH/utils.sh

print_usage() {
    echo "Usage: $PROGNAME"
    echo "Usage: $PROGNAME --help"
    echo "Usage: $PROGNAME --version"
}

print_help() {
    print_revision $PROGNAME $REVISION
    echo ""
    print_usage
    echo ""
    echo "Check nginx Running or not"
    echo ""
    support
}

# Grab the command line arguments

exitstatus=$STATE_WARNING #default
while test -n "$1"; do
    case "$1" in
        --help)
            print_help
            exit $STATE_OK
            ;;
        -h)
            print_help
            exit $STATE_OK
            ;;
        --version)
            print_revision $PROGNAME $REVISION
            exit $STATE_OK
            ;;
        -V)
            print_revision $PROGNAME $REVISION
            exit $STATE_OK
            ;;
        -x)
            exitstatus=$2
            shift
            ;;
        --exitstatus)
            exitstatus=$2
            shift
            ;;
        * )
            echo "Unknown argument: $1"
            print_usage
            exit $STATE_UNKNOWN
            ;;
    esac
    shift
done

# If the source log file doesn't exist, exit
A=`ps -C nginx --no-header | wc -l`
if [ $A -eq 0 ];then
    $ECHO "nginx is not running\n"
    exit $STATE_CRITICAL
else
    $ECHO "nginx is running with $A processes\n"
    exit $STATE_OK
fi

exit $exitstatus

脚本需要可执行权限, 然后和上面添加权限一样添加入nagios即可

邮件报警

http://my.oschina.net/u/615185/blog/69699

nagios发邮件默认是使用本机的smtp服务，需要安装sendmail，但也可以更改commands.cfg中发邮件的命令，使用第三方邮件服务器，这样就不用自己搭建邮件服务器了，但也要注意第三方服务和网络的稳定性。

这里我使用163做邮件服务器，用sendEmail_ 作为客户端来发送邮件

163邮件服务器: smtp.163.com 用户 [email protected] 密码 xxx

wget http://caspian.dotconf.net/menu/Software/SendEmail/sendEmail-v1.56.tar.gz

tar xvf sendEmail-v1.56.tar.gz

cd sendEmail-v1.56

./sendEmail -v -f [email protected] -t [email protected] -u “from nagios” -s smtp.163.com -xu [email protected] -xp xxx -m “test sendEmail” #test

如果发邮件成功则 cp sendEmail /usr/local/bin

chmod +x /usr/local/bin/sendEmail

现在开始配置nagios中邮件报警

cd /usr/local/nagios/

vim etc/objects/contacts.cfg

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                           [email protected]  ; <<***** CHANGE THIS TO YOUR EMAIL ADDRESS ******
}

在email那里加上自己的邮箱，如果有多个可以用逗号隔开

修改etc/objects/commands.cfg中notify_host_by_email和notify_service_by_email:

define command{
    command_name    notify-host-by-email
    command_line    /usr/bin/printf "%b" "***** Nagios *****\n\nNotification Type: $NOTIFICATIONTYPE$\nHost: $HOSTNAME$\nState: $HOSTSTATE$\nAddress: $HOSTADDRESS$\nInfo: $HOSTOUTPUT$\n\nDate/Time: $LONGDATETIME$\n" | /usr/local/bin/sendEmail -f [email protected] -t $CONTACTEMAIL$ -s smtp.163.com -u "** $NOTIFICATIONTYPE$ Host Alert: $HOSTNAME$ is $HOSTSTATE$ **" -xu [email protected] -xp xxx
}

define command{
    command_name    notify-service-by-email
    command_line    /usr/bin/printf "%b" "***** Nagios *****\n\nNotification Type: $NOTIFICATIONTYPE$\n\nService: $SERVICEDESC$\nHost: $HOSTALIAS$\nAddress: $HOSTADDRESS$\nState: $SERVICESTATE$\n\nDate/Time: $LONGDATETIME$\n\nAdditional Info:\n\n$SERVICEOUTPUT$\n" | /usr/local/bin/sendEmail -f [email protected] -t $CONTACTEMAIL$ -s smtp.163.com -u "** $NOTIFICATIONTYPE$ Service Alert: $HOSTALIAS$/$SERVICEDESC$ is $SERVICESTATE$ **" -xu [email protected] -xp xxx
}

service nagios reload

关闭某些服务或重启nagios client机器测试下报警功能