[torkelo]

ELK is about log analytics, Grafana is about Time series & metric analytics and monitoring. The difference might not seem that big but currently it quite a big difference.

Time series are usually more about being able to collect huge amount of metrics. Metrics that can then be combined, averaged, filtered, put through a processing pipeline (analytical functions), summarized by different intervals. All in order to visualize (usually through graphs) recent live trends or long term trends and statistics.

Grafana is all about maximizing the power and ease of use of the underlying time series store so the user can focus om on building informative and nice looking dashboards. It is also about letting users define generic dashboards through variables that can be used in metric queries, this allows users to reuse the same dashboard for different servers, apps or experiments as long as the metric naming follows a consistent pattern.

Grafana also uses Elasticsearch but not for log analytics, but for annotating graphs with event/log information. At some point in in the coming 1-3 years log analytics and metric analytics & visualization is going to converge and be solved/addressed by the same piece of software. But that is tricky right now without sacrificing either domain.