Great walkthrough, working without a flaw. One thing: when copying on a windows machine, and pasting into a shell, the hyphens (‘-’) sometimes have to be re-entered.

With regards,
Mark

https://help.ubuntu.com/community/Nagios3

it’s just one package now!

Enjoy.

The previous useradd nagios command automatically creates the group nagios and adds nagions
userid to it.

# wget http://osdn.dl.sourceforge.net/sourceforge/nagios/nagios-3.0.6.tar.gz
This file does not exist. Best to download it from nagios.org anyway.

I stopped at this point.

Error: Could not read object configuration data!

Here are some things you should check in order to resolve this error:

1. Verify configuration options using the -v command-line option to check for errors.
2. Check the Nagios log file for messages relating to startup or status data errors.

apt-get install build-essential

after that everything worked as suggested.

If you follow these instructions, here’s what you’ll end up with:

Nagios and the plugins will be installed underneath /usr/local/nagios

Nagios will be configured to monitor a few aspects of your local system (CPU load, disk usage, etc.)

The Nagios web interface will be accessible at http://localhost/nagios/

Required Packages:
……………..

Make sure you’ve installed the following packages on your Ubuntu installation before continuing.

Apache 2
GCC compiler and development libraries
GD development libraries

Preparing Your System

First you need to install the following packages

sudo apt-get install apache2

sudo apt-get install build-essential

sudo apt-get install libgd2-xpm-dev

1) Create Account Information

Become the root user.

sudo -s

Create a new nagios user account and give it a password.

#/usr/sbin/useradd nagios

#passwd nagios

On Ubuntu server edition , you will need to also add a nagios group (it’s not created by default). You should be able to skip this step on desktop editions of Ubuntu.

#/usr/sbin/groupadd nagios

#/usr/sbin/usermod -G nagios nagios

Create a new nagcmd group for allowing external commands to be submitted through the web interface. Add both the nagios user and the apache user to the group.

#/usr/sbin/groupadd nagcmd

#/usr/sbin/usermod -G nagcmd nagios

#/usr/sbin/usermod -G nagcmd www-data

2) Download Nagios and the Plugins

Create a directory for storing the downloads.

#mkdir ~/downloads

#cd ~/downloads

Download the source code tarballs of both Nagios and the Nagios plugins (visit http://www.nagios.org/download/ for links to the latest versions). At the time of writing, the latest versions of Nagios and the Nagios plugins were 2.10 and 1.4.10, respectively.

#wget http://switch.dl.sourceforge.net/sourceforge/nagios/nagios-2.10.tar.gz

#wget http://kent.dl.sourceforge.net/sourceforge/nagiosplug/nagios-plugins-1.4.10.tar.gz

3) Compile and Install Nagios

Extract the Nagios source code tarball.

#cd ~/downloads

#tar xzf nagios-2.10.tar.gz

#cd nagios-2.10

Run the Nagios configure script, passing the name of the group you created earlier like so:

#./configure –with-command-group=nagcmd

Compile the Nagios source code.

#make all

Install binaries, init script, sample config files and set permissions on the external command directory.

#make install

#make install-init

#make install-config

#make install-commandmode

Don’t start Nagios yet – there’s still more that needs to be done…

4) Customize Configuration

Sample configuration files have now been installed in the /usr/local/nagios/etc directory. These sample files should work fine for getting started with Nagios. You’ll need to make just one change before you proceed…

Edit the /usr/local/nagios/etc/objects/contacts.cfg config file with your favorite editor and change the email address associated with the nagiosadmin contact definition to the address you’d like to use for receiving alerts.

#vi /usr/local/nagios/etc/objects/contacts.cfg

5) Configure the Web Interface

Install the Nagios web config file in the Apache conf.d directory.

#make install-webconf

Create a nagiosadmin account for logging into the Nagios web interface. Remember the password you assign to this account – you’ll need it later.

#htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin

Restart Apache to make the new settings take effect.

#/etc/init.d/apache2 reload

6) Compile and Install the Nagios Plugins

Extract the Nagios plugins source code tarball.

#cd ~/downloads

#tar xzf nagios-plugins-1.4.10.tar.gz

#cd nagios-plugins-1.4.10

Compile and install the plugins.

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

#make

#make install

7) Start Nagios

Configure Nagios to automatically start when the system boots.

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

Verify the sample Nagios configuration files.

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

If there are no errors, start Nagios.

#/etc/init.d/nagios start
8) Login to the Web Interface

You should now be able to access the Nagios web interface at the URL below. You’ll be prompted for the username (nagiosadmin) and password you specified earlier.

http://localhost/nagios/

Click on the “Service Detail” navbar link to see details of what’s being monitored on your local machine. It will take a few minutes for Nagios to check all the services associated with your machine, as the checks are spread out over time.

9) Other Modifications

If you want to receive email notifications for Nagios alerts, you need to install the mailx (Postfix) package.

#apt-get install mailx

You’ll have to edit the Nagios email notification commands found in /usr/local/nagios/etc/commands.cfg and change any ‘/bin/mail’ references to ‘/usr/bin/mail’. Once you do that you’ll need to restart Nagios to make the configuration changes live.

#/etc/init.d/nagios restart

After I input this command I get the following:
Checking for a BSD-compatible install… /usr/bin/install -c
Checking build system type… i686-pc-linux-gnulibc1
Checking host system type… i686-pc-linux-gnulibc1
Checking for gcc… gcc
Checking for C compiler default output file name… configure: error: C compiler cannot create executables
See ‘config.log’ for more details.

All the steps leading up to this have worked great not sure why this one is giving me troubles. If anyone has any ideas please let me know. thank you.

Adam

I’m pretty new to linux but i followed your manual and everything worked out fine, no errors or warnings. How ever the last command “sudo /etc/init.d/nagios start” does not work – “command not found”. Any advice on how to fix this?

Thanks for a straight forward and easy to use manual, just the thing I needed.

tho.

you will have to answer a few questions during the installation – most of them to do with email.

WARNING: i did try to run this type of installation and nagios wound up working but no plugins would work with it. installing via source didn’t have these problems.

alert messages by either e-mailr. then server engineer easily can manage his network. It can also be configured so that only designated

personnel can view status information for particular services or equipment.

Installation:
Nagios3 is in the repository for Ubuntu 8.10.

we can watch that it will install a number of packages to make it all work.
The following extra packages will be installed:
libfreetype6 libgd2-noxpm libjpeg62 libnet-snmp-perl libperl5.10 libpng12-0
libradius1 libsensors3 libsnmp-base libsnmp15 libsysfs2 libtalloc1
libwbclient0 nagios-images nagios-plugins nagios-plugins-basic
nagios-plugins-standard nagios3-common nagios3-doc radiusclient1
samba-common smbclient snmp

Suggested packages:
libfreetype6-dev libgd-tools libcrypt-des-perl libdigest-hmac-perl
libdigest-sha1-perl libio-socket-inet6-perl lm-sensors nagios2 nagios-text
nagios whois nagios-nrpe-plugin smbfs
The following NEW packages will be installed:
libfreetype6 libgd2-noxpm libjpeg62 libnet-snmp-perl libperl5.10 libpng12-0
libradius1 libsensors3 libsnmp-base libsnmp15 libsysfs2 libtalloc1
libwbclient0 nagios-images nagios-plugins nagios-plugins-basic
nagios-plugins-standard nagios3 nagios3-common nagios3-doc radiusclient1
samba-common smbclient snmp
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Once it is installed run a pre-flight check to verify it is working correctly.