Review: 3 Web stack monitors in the cloud
Monitoring services from Boundary, Circonus, and Librato combine simple setup and richly different capabilitiesFollow @peterwayner
Circonus: Monitoring from the ground up
Whereas Boundary paints the big picture with one brush, Circonus has a different brush for every color in the rainbow. The core of the system is your collection of "checks"-- that is, a query executed to test the system. The simplest may be loading a URL and tracking how long it takes for the data to arrive. The most complex may be elaborate queries on the database to track back-end performance.
There are a surprisingly large number of checks -- more than several dozen. Some dig into remote processes like databases, and others gather information from third-party sources like Google Analytics. There are even some generic ones that fetch JSON blobs from URLs. The tools typically provide a wizardlike progression of forms that culminate in testing the check before saving it.
Circonus takes the data from these checks and turns them into metrics. My request for a URL, for instance, generated six values ranging from the time it takes for the first byte to arrive to the total number of bytes delivered. The price of your Circonus package will depend upon the number of metrics you store. Some checks deliver more metrics, and you can configure how they store the data.
Once the data is in Circonus, you can start graphing the information and putting it on dashboards. Circonus has a great collection of graphing widgets, but they range in complexity and capability. The basic gauge, for instance, wanted me to specify a minimum and maximum value, a task it should do on its own. Ideally, it should be easy to configure the meter to start flashing when a value moves out of a historical range.
The map widget, on the other hand, will plot out locations on a global map. But it's not just any view of the world. You can choose a map based on the old Mercator projection that has distorted our view of the world since grade school, or you can pick among seven other options, including the Gall-Peters, an "equal area" view that will save you from overestimating the amount of land in Greenland. If only my website had readers in Greenland.
Circonus pricing is tiered. The lowest level, called Copper, covers two servers for $50 per month. The price per server falls as you add servers, running up to $750 per month to watch 50 servers. Each package includes a set number of metrics.
Circonus will install its monitoring solution inside your data center for a negotiated price, an option that might be more attractive than a hosted service to large enterprises and governments.
Circonus maintains a collection of agents around the world that can be summoned to ping your site.