Overview¶
Objectives¶
The Ceilometer project was started in 2012 with one simple goal in mind: to provide an infrastructure to collect any information needed regarding OpenStack projects. It was designed so that rating engines could use this single source to transform events into billable items which we label as “metering”.
As the project started to come to life, collecting an increasing number of meters across multiple projects, the OpenStack community started to realize that a secondary goal could be added to Ceilometer: become a standard way to collect meter, regardless of the purpose of the collection. For example, Ceilometer can now publish information for monitoring, debugging and graphing tools in addition or in parallel to the metering backend. We labelled this effort as “multi-publisher”.
Most recently, as the Heat project started to come to life, it soon became clear that the OpenStack project needed a tool to watch for variations in key values in order to trigger various reactions. As Ceilometer already had the tooling to collect vast quantities of data, it seemed logical to add this as an extension of the Ceilometer project, which we tagged as “alarming”.
Metering¶
If you divide a billing process into a 3 step process, as is commonly done in the telco industry, the steps are:
Ceilometer’s initial goal was, and still is, strictly limited to step one. This is a choice made from the beginning not to go into rating or billing, as the variety of possibilities seemed too large for the project to ever deliver a solution that would fit everyone’s needs, from private to public clouds. This means that if you are looking at this project to solve your billing needs, this is the right way to go, but certainly not the end of the road for you. Once Ceilometer is in place on your OpenStack deployment, you will still have several things to do before you can produce a bill for your customers. One of you first task could be: finding the right queries within the Ceilometer API to extract the information you need for your very own rating engine.