Sys Admin Tools 0.1 - Installing and Monitoring with Icinga

Welcome to the third and final part of my 0.1 release. In this post I will discuss the steps necessary in order to in install and configure Icinga from source – at a later time I will post about installation from an RPM which a colleague of mine is working on.

We must install the prerequisites for Icinga before we move on, these include; Apache, GCC Compiler, C/C++ development libraries, and GD development libraries. Use the following command (as root or sudo) in order to install the necessary packages for RedHat Based distributions;

            yum install httpd gcc glibc glibc-common gd gd-devel libjpeg libjpeg-devel

            libpng libpng-devel net-snmp net-snmp-devel

Once you have the prerequisites installed you will need to the follow the upcoming steps in order to successfully install your Icinga Core and Icinga Web from source code.

Create your new icinga user account and give it a password

useradd –m icinga && passwd icinga

Create the required group named “icinga”

groupadd  icinga

We will then need to create a new group called “icinga-cmd” and adding the systems web user and Icinga user to this group will allow for them to use the classic web interface to send commands to Icinga.

groupadd icinga-cmd

usermod –a –G icinga-cmd icinga

usermod –a –G icinga-cmd apache

Change your current working directory to a location of your choosing and download and extract the following tarball files (as root or sudo) – the purpose of this post we will use “/usr/src” as our directory;

cd /usr/src/

Files to download;

wget http://sourceforge.net/projects/icinga/files/icinga/1.3.0/icinga-1.3.0.tar.gz/download

wget http://sourceforge.net/projects/icinga/files/icinga-web/1.3.0/icinga-web-1.3.0.tar.gz/download

wget http://sourceforge.net/projects/nagiosplug/files/nagiosplug/1.4.15/nagios-plugins-1.4.15.tar.gz/download

Next we will extract the Icinga Core and prepare it for installation;

tar –zxvf  icinga-1.3.0.tar.gz

cd /usr/src/icinga-1.3.0/

./configure --with-command-group=icinga-cmd (use the --help arguments for additional options)

            make all

To complete a full installation of Icinga from source you can simply enter the following command; “make fullinstall” – the default installation directory is “/usr/local/icinga/”. (Note: Do not start Icinga yet!)

Before we continue we must change the email address inside of the “/usr/local/icinga/etc/objects/contacts.cfg” file – this address is used for notification emails, review the other options in the file for additional changes you may want to make.

Icinga does come with a Classic Web Interface already built in, use the following commands to set up and configure your web interface that will be used to administer your Icinga server – if you would like to know how to install the new Icinga-Web follow this link.

cd /usr/src/icinga-1.3.0/

            make cgis

            make install-cgis

            make install-html

            make install-webconf

Create the icingaadmin account that will be logging into the Icinga classic web interface and then restart your web server – the account is determined by the entry found in the “/usr/loca/icinga/etc/objects/contacts.cfg” file’s “contact_name” option.

            htpasswd -c /usr/local/icinga/etc/htpasswd.users icingaadmin

            /etc/init.d/httpd restart

Because Icinga is backwards compitable with Nagios, it uses all of Nagios’ available plugins – these will need to be installed as well.

            cd /usr/src/nagios-plugins-1.4.15

            ./configure --prefix=/usr/loca/icinga --with-cgiurl=/icinga/cgi-bin --with-htmurl=/icinga --with-nagios-user=icinga --with-nagios-group=icinga

            make && make install

IMPORTANT: The commands above much also be executed on ALL machines that are to be monitored by Icinga. 

You may run into the always annoying encounters with SELinux settings on RedHat distributions, to perform an easy fix you can simply set your SELinux settings to permissive mode (setenforce 0) – the Icinga documentation provides the necessary commands in order to fix the SELinux issue, the commands are found below;

            

            chcon –R –t httpd_sys_script_exec_t /usr/local/icinga/sbin/

            chcon –R –t httpd_sys_content_t /usr/local/icinga/share/

            chcon –t httpd_sys_script_rw_t /usr/local/icinga/var/rw/icinga.cmd

This concludes the installation of your new Icinga server, you are now able to start your Icinga service – be sure to add it to your start up scripts;

            chkconfig --add icinga

            chkconfig icinga on

            /etc/init.d/icinga start

In order to access your Classic Web Interface you will need to redirect yourself to the following URL – http://localhost/icinga/ or http://yourdomain.com/icinga/

Full Size: http://matrix.senecac.on.ca/~gcasella/SBR/icinga.png

IMPORTANT: If iptables is enabled you MUST add the exception for port 80 to be accepted –     iptables –A INPUT –p tcp –m tcp –dport 80 –j ACCEPT

The following video will show a very small demonstration of what Icinga looks like after it is installed, with also a simple notification sample. Note that it is a demonstration on my virtual servers at home and is not yet ready for production. 

To be continued... Stay tuned for my 0.2 release where I will 
demonstrate Icinga in action, showing configuration 
and real-time monitoring on Fedora-ARM machines.

---

Gian-Luca Casella -- Last Updated on Tuesday, March 26, 2011

Sys Admin Tools 0.1 - Icinga vs Nagios

Welcome to part two of my three part series of my 0.1 release. During this blog entry I will be discussing what I am sure many have asked when it comes to Network Monitoring Tools, “Nagios or Icinga?”. These two tools serve the exact same purpose, to monitor devices through a network, but what exactly is Nagios or Icinga?

The main differences between these two monitoring tools are strictly their architecture. Below is an image of both architectures with more information that will follow.

                              Icinga                                                         Nagios

When using the Nagios architecture each add-on that is applied will need to suit its interfaces and formats, for example if you need MySQL output you will need your own interface in order to translate it to the Nagios Core. Ultimately if you need to use 5 different output formats than you would need to write 5 different passive interfaces, making this the main structural difference between Icinga and Nagios.

However, because of Icinga’s API developers will ONLY need to know the API and program off of it. The API has the ability to translate any required output directly to the Icinga Core. Also, like Nagios, the Icinga Core communicates to a database via the Icinga Data Out Module (IDOMOD) and Icinga Data Out to Database (IDO2DB). However the IDODB differs significantly from the Nagios Data out Database (NDODB), not only does IDOMOD support the standard MySQL Database but also other popular ones such as Oracle and PostgreSQL.

Note: Icinga must be installed with IDOUtils, which is what allows Icinga to support databases outside of MySQL.

Each instance/component of the Icinga architecture (Core/WebUI&API/Database) can run on their own separate servers while still being connect to each other by a switch. The advantage to this is that if a component were to fail, for example the Icinga Core, you could have a second Icinga Core to take its job in case of emergencies.

And lastly, unlike the Nagios Web User Interface which runs on the same instance as the Nagios Core, Icinga Web is a standalone software which communicates with the database through the Icinga API.

The folks at Icinga have provided users with a comparison chart that allows for a simpler view of what Icinga has to offer over Nagios.

This concludes Part Two of my Three Part series of my 0.1 release, for any additional information regarding the difference between the Nagios and Icinga monitoring tools you can follow the links below;

http://www.icinga.org/about/nagios/

http://www.icinga.org/about/nagios/architecture/

---

Gian-Luca Casella -- Last Updated on Tuesday, March 22, 2011

Sys Admin Tools 0.1 - Analysis

This is part one of a three part posting of a project that I am working on a project for CDOT at Seneca College that deals with deploying certain System Administrative Tools not only on the various machines/architectures within the CDOT environment, but also on a series of machines within the Fedora community. This project requires us to implement, fine tune, deploy, and document the following Administrative Tools explicitly within CDOT; Icinga/Nagios, Func, and Puppet. If you are interested in knowing more about this specific project visit the SBR600 Project Page.[Sys Admin Tools for ARM Build Farm]

Throughout the course of this project I will be working with two other colleagues. Each one of them will be working on a different System Administration Tool. They have created in their own blogs so that anyone within the Fedora community and CDOT would be able to monitor their progress on their specific Administration Tools – the links to their blogs along with their respected System Administration Tool is listed below.

Pirathapan Sivalingam – Puppet

Tim Furzer  – Func

Gian-Luca Casella – Icinga/Nagios

Whats Next?
Before any actual work can take place the proper research of all of these System Administration Tools must be conducted in order to determine what the best choice is for CDOT’s machines, being a System Administrator you must realize that not everything is full proof, so some extensive testing will need to be done in order to have a very smooth deployment of these tools.

Because we will be working with a series of different machines, architectures, and operating systems both within the open-source community and specifically CDOT we need to be able to understand how their systems function. Since the machines within CDOT run on a wide variety of platforms we require vital information from them, such as their current Operating System and architecture which will allow us to completely replicate them ensuring that there is less room for error during implementation and deployment of these System Administration Tools.

If you would like to continue reading please redirect yourself to Part Two of this post, in it there will be discussion on the following; Icinga vs. Nagios.

---

Gian-Luca Casella -- Last Updated on Tuesday, March 15, 2011