For years we’ve been trying to educate the world about the benefits and the ideology behind free software. We’ve been working hard to enlighten as many people and companies as possible, but somewhere along the way I believe we forgot our goal. Our goal was to get Linux, free software and open source into peoples homes, offices and even the data centers and believe it or not, WE ARE HERE!!!

Open source has gone into a new phase and whether we like it or not the rules have changed. Of course this didn’t happen over night, this is the result of a series of decisions a couple of companies made. Red Hat decided to release an enterprise version of their Linux distribution and begun to compete with Microsoft, Sun, HP and others about the space in the data centers and not too long ago Red Hat also bough the popular open source application server JBoss. Novell bought SUSE and pretty much replaced NetWare with SUSE Linux and joined the party in the data centers.

A company that definitely made a difference in leading open source into the next phase is Sun Microsystems. In the past few years Sun has been changing the licensing of Java to open source and also released OpenSolaris an open source version of Solaris. As another step in Sun’s open source strategy they bought two very significant open source projects, MySQL and VirtualBox. Sun isn’t the only company to buy open source projects at the moment and not to long ago Nokia bought Trolltech and Citrix bough Xen Source.

At this new playground there’s a new set of rules to live up to that the open source-community never faced before. At this playground of companies, business agreements, economics and profitability there’s no room for decisions based on ideology. We need to help these companies find ways to make their decisions so that they do not interfere with the ideology behind open source and so that these companies can benefit from their decisions.

It’s no longer the open source-community’ believe in their ideology that brings open source further, open source has silently taken the step into the commercial world and whatever you all think about that it was all of us that brought it there. We got what we asked for and now it’s time to learn to play by the new rules.

I’ve been using Nagios for system and network monitoring both at home and in an enterprise environment. At home i monitor services and hardware of two Linux servers and an IBM AS/400. Professionally I’ve been monitoring over 400 Linux-, Unix-, Mac- and Windows servers together with network devices such as switches, routers and load balancers.

Nagios is designed for Linux but should run nice on any *NIX system and requires a web server preferably Apache. Nagios monitors network services such as TCP, SMTP, POP, IMAP, HTTP, DNS, SSH, PING… etc. and host resources such as processor load, disk usage and number of users logged in. Nagios is also capable of host hierarchies for hosts and networks resources to detect network outages. The latest stable version of Nagios as I write this is Nagios 2.1.0 and latest development release is Nagios 3.0rc3.

Nagios is a scalable monitoring system that can have many nodes providing monitoring information to a central Nagios server with the web interface to present the collected information. In this case you set up the nodes to collect information through active and passive checks from the different hosts and network resources in your network and then sends then to a central Nagios server as passive checks. Except the web interface Nagios provides notifications of failing checks through e-mail, SMS or jabber with some 3rd party software eg. SMTP-server, SMS-gateway or Jabber-gateway.

The only inconvenience with Nagios is that the configuration is stored in text files. In large environment you end up with giant text files of configuration if you don’t create your own configuration file structure. Use of agents such as NRPE doesn’t really make your configuration file problem any smaller. To Nagios benefit I have to say that it’s fairly easy to write your own plugins, either for better functionality or to monitor your companies internally developed services.

During the time I’ve been using Nagios I have coded a few plugins for Nagios in Perl. Two of those plugins are remote checks of MySQL, first with a SELECT NOW() to check that it responds and the other check is of MySQL replication checking that replication is running and how many seconds behind the master it is. There are also two hard drive checks, one local using regular shell command df and the other check is a remote check using SNMP with the command snmpdf. These plugins can be found at: http://amelia.linuxchick.se/code/nagios-plugins/

For more information on Nagios and to download it visit http://www.nagios.org.

A screenshot of my Nagios running at home http://amelia.linuxchick.se/screenshots/nagios.jpg.