I’m sure that many of the eyeos/oneye users have some Linux servers to administer (like the servers of a small company or even your home Linux box), so I’d like to indicate you a great free and open-source monitoring tool: Monitorix. It is a lightweight system monitoring tool written in Perl by Jordi Sanfeliu, a Catalan guy. It has a CGI web interface displaying RRDTOOL graphs, allowing to keep historical data. I’ve used it for 2 years and it helped me a lot in understanding the health and load status of my servers, showing me what had to be optimized. I also have made some contributions to the project (for example, I designed the MySQL graphs, which was then implemented by Jordi).
It can monitor: CPUs, memory, disks (usage and activity), temperatures, fans, network traffic, kernel activity, services requests (Apache, Nginx, MySQL, Samba, FTP, Sendmail, and many others…) and it can also send mail alerts.
It’s not as feature-rich as other tools like Nagios, but you’ll love its extreme lightness! (and if you have just a few small servers, you don’t need the complexity of Nagios!)
I hope you’ll find it useful…Have a nice day!