We often get questions about the kind of hardware requirements needed for a particular Nagios installation. As covered in a previous article, this is often a very difficult question to answer since monitoring environments differ so much. Most people assume that for a large Nagios installation, it’s a matter of simply adding enough CPU’s to the machine to handle the workload that it’s given. Although having enough CPU power is important, I’ve found that it’s ultimately not the biggest hardware limitation to the system. A large Nagios installation creates an enormous amount of disk activity, and if the hard disk can’t keep up with the constant traffic flow that needs to happen, all of those precious CPU’s are simply going to wait in line to be able to do what they need to do on the system. I’ve talked to some users who have spent some serious money on hardware to have insanely fast disks to handle their workload, but I wanted to do some experiments in-house for those users who may need to have better performance on a budget. I want to give special thanks to Nagios community members Dan Wittenberg and Max Schubert for documenting some of the tricks that you guys pioneered on this topic.
Continue reading ‘Nagios Performance Tuning – Tech Tips: Understanding Disk I\O’