NAGIOS MEMBER WITH NRPE

How To Monitor Remote Linux Host using Nagios 3.0

Download Nagios Plugins and NRPE Add-on

1. Create nagios account 2. Install Nagios Plugins 3. Install NRPE 4. Setup NRPE to run as daemon 5. Modify the /usr/local/nagios/etc/nrpe.cfg

steps to install Nagios Plugins and NRPE on the remote host

Download following files from Nagios.org and move to /home/downloads:

• nagios-plugins-1.4.11.tar.gz • nrpe-2.12.tar.gz

Create nagios account[remotehost]# useradd nagios[remotehost]# passwd nagios

3. Install nagios-plugin[remotehost]# cd /home/downloads[remotehost]# tar xvfz nagios-plugins-1.4.11.tar.gz[remotehost]# cd nagios-plugins-1.4.11[remotehost]# export LDFLAGS=-ldl

[remotehost]# ./configure --with-nagios-user=nagios --with-nagios-group=nagios --enable-redhat-pthread-workaround[remotehost]# make[remotehost]# make install

[remotehost]# chown nagios.nagios /usr/local/nagios[remotehost]# chown -R nagios.nagios /usr/local/nagios/libexec/

4. Install NRPE[remotehost]# cd /home/downloads[remotehost]# tar xvfz nrpe-2.12.tar.gz[remotehost]# cd nrpe-2.12

[remotehost]# ./configure[remotehost]# make all[remotehost]# make install-plugin[remotehost]# make install-daemon[remotehost]# make install-daemon-config[remotehost]# make install-xinetd

[remotehost]#vim /etc/xinetd.d/nrpe

only_from = 127.0.0.1 192.168.1.2

Modify the /etc/services and add the following at the end of the file.[remotehost]#vim /etc/services

nrpe 5666/tcp # NRPE

[remotehost]#service xinetd restart

[remotehost]# netstat -at | grep nrpe tcp 0 0 *:nrpe *:* LISTEN

[remotehost]# /usr/local/nagios/libexec/check_nrpe -H localhost

NRPE v2.12

command[check_disk]=/usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/hda1

[remotehost]#/usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/hda1

DISK CRITICAL - free space: / 6420 MB (10% inode=98%);| /=55032MB;51792;58266;0;64741

Configuration steps on the Nagios monitoring server to monitor

NAGIOS SERVER

1. Download NRPE Add-on

Download nrpe-2.12.tar.gz from Nagios.org and move to /home/downloads:

2. Install check_nrpe on the nagios monitoring server[nagios-server]# tar xvfz nrpe-2.12.tar.gz[nagios-server]# cd nrpe-2.1.2[nagios-server]# ./configure[nagios-server]# make all[nagios-server]# make install-plugin

./configure will give a configuration summary as shown below:

*** Configuration summary for nrpe 2.12 05-31-2008 ***:

General Options:————————-NRPE port: 5666NRPE user: nagiosNRPE group: nagiosNagios user: nagiosNagios group: nagios

[nagios-server]# rpm -ivh openssl-devel-0.9.7a-43.16.i386.rpm krb5-devel-1.3.4-47.i386.rpm zlib-devel-1.2.1.2-1.2.i386.rpm e2fsprogs-devel-1.35-12.5.

el4.i386.rpmwarning: openssl-devel-0.9.7a-43.16.i386.rpm: V3 DSA signature: NOKEY, key ID db42a60ePreparing… ########################################### [100%]1:e2fsprogs-devel ########################################### [ 25%]2:krb5-devel ########################################### [ 50%]3:zlib-devel ########################################### [ 75%]4:openssl-devel ########################################### [100%]

[nagios-server]#/usr/local/nagios/libexec/check_nrpe -H 192.168.0.8

NRPE v2.12

NOTE:- 192.168.0.8 is client IP

[nagios-server]#vim /usr/local/nagios/etc/objects/remotehost.cfg

define host{

use linux-serverhost_name remotehostalias Remote Hostaddress 192.168.1.3contact_groups admins}

define service{

use generic-serviceservice_description Root Partitioncontact_groups adminscheck_command check_nrpe!check_disk}

[nagios-server]#vim /usr/local/nagios/etc/nagios.cfg

cfg_file=/usr/local/nagios/etc/objects/remotehost.cfg {add This line}

[nagios-server]# service nagios reload

NOTEERROR:-

checking for SSL headers... configure: error: Cannot find ssl headersThen install this packages

yum install openssl-devel

HELP[remotehost]# make all

cd ./src/; make ; cd ..

make[1]: Entering directory `/usr/local/nrpe-2.13/src'

make[1]: Nothing to be done for `all'.

make[1]: Leaving directory `/usr/local/nrpe-2.13/src'

*** Compile finished ***

If the NRPE daemon and client compiled without any errors, you

can continue with the installation or upgrade process.

Read the PDF documentation (NRPE.pdf) for information on the next

steps you should take to complete the installation or upgrade.

[remotehost]# make install-plugin

cd ./src/ && make install-plugin

make[1]: Entering directory `/usr/local/nrpe-2.13/src'

/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/libexec

/usr/bin/install -c -m 775 -o nagios -g nagios check_nrpe /usr/local/nagios/libexec

make[1]: Leaving directory `/usr/local/nrpe-2.13/src'

[remotehost]# cd ./src/ && make install-plugin

/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/libexec

/usr/bin/install -c -m 775 -o nagios -g nagios check_nrpe /usr/local/nagios/libexec

[remotehost]#make install-plugin

/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/libexec

/usr/bin/install -c -m 775 -o nagios -g nagios check_nrpe /usr/local/nagios/libexec

[remotehost]#/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/libexec

[remotehost]#[remotehost]#/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/libexec

Command not found. Failed to search for file: Invalid search term

[remotehost]#/usr/bin/install -c -m 775 -o nagios -g nagios check_nrpe /usr/local/nagios/libexec

[remotehost]#make install-daemon

/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/bin

/usr/bin/install -c -m 775 -o nagios -g nagios nrpe /usr/local/nagios/bin

[remotehost]#/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/bin

[remotehost]#/usr/bin/install -c -m 775 -o nagios -g nagios nrpe /usr/local/nagios/bin

[remotehost]#make install-daemon-config

make: *** No rule to make target `install-daemon-config'. Stop.

[remotehost]#cd ..

[remotehost]# make install-daemon-config

/usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/etc

/usr/bin/install -c -m 644 -o nagios -g nagios sample-config/nrpe.cfg /usr/local/nagios/etc

[remotehost]# /usr/bin/install -c -m 775 -o nagios -g nagios -d /usr/local/nagios/etc

[remotehost]# /usr/bin/install -c -m 644 -o nagios -g nagios sample-config/nrpe.cfg /usr/local/nagios/etc

[remotehost]# make install-xinetd

/usr/bin/install -c -m 644 sample-config/nrpe.xinetd /etc/xinetd.d/nrpe

[remotehost]# /usr/bin/install -c -m 644 sample-config/nrpe.xinetd /etc/xinetd.d/nrpe

[remotehost]# vim /etc/xinetd.d/nrpe

[remotehost]# vim /etc/services

[remotehost]# service xinetd restart

Stopping xinetd: [ OK ]

Starting xinetd: [ OK ]

[remotehost]# netstat -at | grep nrpe

tcp 0 0 *:nrpe *:* LISTEN

[remotehost]# /usr/local/nagios/libexec/check_nrpe -H localhost

NRPE v2.13

[remotehost]# vim /usr/local/nagios/etc/nrpe.cfg

[remotehost]# /usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/hda1

DISK CRITICAL - /dev/hda1 is not accessible: No such file or directory

[remotehost]# fdisk -l

Disk /dev/sda: 250.1 GB, 250059350016 bytes

255 heads, 63 sectors/track, 30401 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x000c1873

Device Boot Start End Blocks Id System

/dev/sda1 * 1 128 1024000 83 Linux

Partition 1 does not end on cylinder boundary.

/dev/sda2 128 4590 35840000 83 Linux

/dev/sda3 4590 4851 2097152 82 Linux swap / Solaris

/dev/sda4 4851 30402 205236224 5 Extended

/dev/sda5 4851 30402 205235200 83 Linux

[remotehost]# /usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/sda1

DISK OK - free space: /boot 880 MB (94% inode=99%);| /boot=53MB;787;885;0;984

[remotehost]# /usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/sda2

DISK OK - free space: / 13405 MB (40% inode=85%);| /=19295MB;27560;31005;0;34450

[remotehost]# /usr/local/nagios/libexec/check_load -w 15,10,5 -c 30,25,20

OK - load average: 0.01, 0.10, 0.10|load1=0.010;15.000;30.000;0; load5=0.100;10.000;25.000;0; load15=0.100;5.000;20.000;0;

[remotehost]# /usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/hda1

DISK CRITICAL - /dev/hda1 is not accessible: No such file or directory

[remotehost]# /usr/local/nagios/libexec/check_disk -w 20% -c 10% -p /dev/sda1

DISK OK - free space: /boot 880 MB (94% inode=99%);| /boot=53MB;787;885;0;984

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