Nagios and Oreon (Nagios web front end) installation

What is Nagios ?

Nagios® is a host and service monitor designed to inform you of network problems before your clients, end-users or managers do. It has been designed to run under the Linux operating system, but works fine under most *NIX variants as well. The monitoring daemon runs intermittent checks on hosts and services you specify using external "plugins" which return status information to Nagios. When problems are encountered, the daemon can send notifications out to administrative contacts in a variety of different ways (email, instant message, SMS, etc.). Current status information, historical logs, and reports can all be accessed via a web browser.

What is oreon ?

Oreon© is an Open Source monitoring solution based on Nagios. It offers to this monitoring standard a new front end and brings it a panel of new functionalities.

Oreon Plugins

Nagios 1.2 and Oreon 1.2.2 installation on Debian


Edit you /etc/apt/sources.list file enter any of the following two source list and save the file

deb stable main
deb-src stable main

deb stable main
deb-src stable main

deb stable main
deb-src stable main

If you modified this file, you must update the package list

# apt-get update

Put an IP address in /etc/network/interfaces

Put in the file /etc/hosts, the link between IP adress and Hostname.

Restart network service

# /etc/init.d/networking restart

Packages Need to Install

C Compilator and sudo installation

# apt-get install gcc make sudo g++

Web server installation : Apache 2

# apt-get install apache2

Mysql 4 database installation

# apt-get install mysql-server

PHP4 tool installation

# apt-get install php4 php4-gd php4-cgi php4-mysql libapache2-mod-php4

Nagios 1.2 installation

You can download compressor file on :

Take last version (At the moment, the V0.3 of November 17, 2004).

Save it in /tmp

Uncompress it

# tar xzf install_nagios_by_oreon-v0.3.tar.gz

Now, you should have this directory :


Edit this file

In section INSTALL / check for httpd directory , replace

/etc/apache2/conf by /etc/apache2
DIR_APACHE="/etc/apache2/conf" by DIR_APACHE="/etc/apache2"

Save and close the file

Execute installation ./, any questions asked 

install freetype yes
install jpeg yes
install png yes
install gd yes
install rrdtool yes
install net-snmp
      System Contact
      System Location
install nagios 1.2 yes
restart Apache yes
password nagiosadmin [put password]
start nagios server yes

Once finished insallation, modify this file /etc/init.d/nagios

Search this lign su –l and delete l so have only su –

Check the Nagios home : /home/nagios/. If don't exist, creat it

# cd /home
# mkdir nagios
# chown nagios.nagios nagios
# chmod 775 nagios

OREON 1.2.2 installation

You can download compressor file on :

Take last version (at the moment, the 1.2.2 of September 9, 2005).

Save it in /tmp

uncompress it

# tar xzf oreon-1.2.2.tar.gz

Now, you should have this directory


Execute installation ./, any questions asked


Are you sure to continue y
Where is installed nagios [Just press Enter]
Where do I install Oreon [Just press Enter]
Where is sudo [Just press Enter]

Last packages to install

nmap installation: Tool for auto-detect in Oreon

# apt-get install nmap

Oreon graphic tool installation

# apt-get install librrds-perl libgd-gd2-perl wget

Perl tool installation for a few plugins

# apt-get install libnet-snmp-perl

Final Steps

Delete oreon.conf file in apache2 directory

# rm /etc/apache2/conf.d/oreon.conf

Creat symbolic link between rrdtool directory.

# ln -s /usr/local/rrdtool-1.0.49/ /usr/local/rrdtool

So restart 3 services

# /etc/init.d/apache2 restart

# /etc/init.d/mysql restart

# /etc/init.d/nagios restart

Web interface Setup

Use web browser and go this URL : http://serverIPaddress/oreon/ First time, you finalize Oreon installation

This will open webinterface now you need to click on "start" button

If you don't have this page the FIRST TIME, entrer this URL: http://serverIPaddress/oreon/install/setup.php

Select I Accept and click on Next

Check environment configuration.

Click on Next

This step, all statuts must be on OK But there, we have a problem with PHP memory limit.

To correct this,edit this file:

# vi /etc/php4/apache2/php.ini

Replace this lign memory_limit = 8M by memory_limit = 16M
Un-comment this lign

Save and close this file

Restart apache2

# /etc/init.d/apache2 restart

Come back on web navigator and click on Recheck

Click on Next

In theory, there aren't root password for mysql

Give name for mysql database

Give it password

Precise server address : in theory, put localhost

Click on Next

Give Oreon administrator login

Give it password

Put Firstname




Click on Next

If there aren't errors, click on Next, else come back to correct them.

So, your minimal installation and configuration is finished.

Click on interface or enter this URL: http://serverIPaddress/oreon/

If you see this red message in this page

Installation Directory is accessible. Delete this directory to prevent security problem

So you must delete install directory in Oreon

# rm -Rf /usr/local/oreon/install/

Re-fresh this page and the message must not be there.

You can log.

The first time, you must generate the plugin file.

Plugin generation

Click on Options on the top page and plugins on the left

Click on Generate

Nagios and runlevel

At this installation end, Nagios don't start with the computer. You must start manually this service.

If you want to start nagios with computer, you must execute this command

# cd /etc/init.d/

# update-rc.d nagios defaults

So, if you computer (re)start, Nagios service will be started.