Have you ever considered how you will monitor your production kvm guest machines? You could monitor them just like any other physical machine but that is not considered best practice in the virtualization industry and in fact touted as a shortcoming in virtual machine management practice. Well..there is a tool being developed by Redhat that relies on the libvirt interface for monitoring virtual machines based on kvm or any other hypervisor supported by the libvirt interface. This means that it obviously will only work for kvm guests being managed by tools based on libvirt such as virt-manager, virtsh etc. and will not work for your kvm guests being managed by command line.

What is Nagios?

Nagios is one of the most popular open source monitoring systems and considered the grandfather of opensource monitoring on linux. It is available by default in all major linux distributions and provides a solid, reliable framework for systems and network monitoring. One of the best features of nagios is how easy you can plugin your custom scripts to extend it’s capabilities. This is where nagios-virt comes in.

More information can be found on nagios here: Nagios Monitoring

The nagios-virt tool

Nagios-virt is an open source nagios plug-in monitor maintained by redhat designed for using the libvirt interface to monitor your virtual machines. The nagios-virt tool can be easily integrated with your current nagios installation if you already have one or can be used to setup a new nagios installation.

The project pages for nagios-virt can be found here: Nagios support for virtualization. It provides documentation for installation and basic instructions for getting it up and running. At the time of this writing it is only at version 0.2.0 so still a young project but development is happening at a rapid case as is usually the case for young projects. If you manage your kvm guests using libvirt tools, you should consider giving this a try if monitoring is something you need to do.