[bbrazil]

Prometheus developer here.

> Did you (or has anyone else) migrate your legacy data from graphite to prometheus?

Prometheus isn't intended as a long-term data store, so there's usually not much point. The data model is also quite different.

> What's the grafana support like on top?

Grafana supports Prometheus as a 1st class integration, and when I was speaking with the Raintank team in person they are very supportive of Prometheus.

> Do you need to run a proxy or something to support the same querying or does it require reworking all the existing graphs?

The data model and query language is more powerful and very different, you have to redo all the graphs.

To aid transition we have https://github.com/prometheus/graphite_exporter which will take in graphite formatted exports from your clients, and convert it to the format Prometheus likes.