The Best of Both Worlds

Metric data can be collected by the Prometheus Node Exporter, Telegraf, or any other exporter that meets the requirements of Prometheus. All data is sent first to Prometheus – Chronograf and Kapacitor do not have a role in this setup – and the data in Prometheus is downsampled to suit your needs: Instead of saving all of the data, it might be fine to save exemplary data records for longer periods of time, because they are equally meaningful. For example, a downsampling approach could be to keep all data from the past four weeks, as well as one data set for each day of the previous two months and one data set per week of the last year.

In this scenario, you slot an adapter between Prometheus and InfluxDB that communicates with the Prometheus server on one side and with InfluxDB on the other. According to the downsampling rules, the adapter reads the required data from Prometheus and saves it in InfluxDB. From Prometheus' point of view, all this is completely transparent and does not increase load to a noticeable extent.

Such a construct does not mean you sacrifice the advantage of a single point of administration. Although InfluxDB is available in a setup of this type as a data source parallel to Prometheus, if Grafana is used as the tool to visualize the data, matching dashboards can also be integrated into Grafana for InfluxDB. The end result is the same interface, but one that accesses another source in the background.

As a basic rule, if you combine Prometheus and InfluxDB, you get the best of both worlds.

Conclusions

Neither the TICK Stack nor Prometheus are panaceas when it comes to MAT. When comparing the two products, you need to bear in mind that their objectives are not the same: The TICK Stack sees itself as a solution to processing measurement data that can also act as a platform for monitoring, alerting, and trending.

Therefore, InfluxDB has functions that are missing in Prometheus. On the other hand, Prometheus sees itself more as a pure MAT solution and gets by with less overhead. Your own requirements should determine whether you choose the TICK Stack or Prometheus for your situation.

If you want to run MAT on numerical measurements, you'll be better off with Prometheus and probably reach your goal faster. However, if you need more flexibility and want to log events as text and collect metric data, you should have a look at the TICK Stack.

Always remember that the two solutions can be combined. If you ultimately use the TICK Stack as long-term storage for your Prometheus data, you can run Telegraf, Kapacitor, and Chronograf in parallel with Prometheus and let them handle the work.

The Author

Martin Gerhard Loschwitz is a Telekom Public Cloud Architect for T-Systems and primarily works on topics such as OpenStack, Ceph, and Kubernetes.