The new dashboard in Ceph Luminous

Dashboards in Ceph have always been a bit of a problem. In the past, I tried first to deploy and run Calamari, but it was a complete failure. I talked about my disgraces in this blog post, and there I also suggested a way better solution: Ceph Dash. But now with the release of Luminous, Ceph is trying again to have its own dashboard. Will it be good this time?

How to migrate Ceph storage volumes from Filestore to Bluestore

In my two previous posts about the new Ceph 12.2 release, named Luminous, I first described the new Bluestore storage technology, and I then upgraded my cluster to the 12.2 release. By default, Ceph can run both OSD using Filestore and Bluestore, so that existing clusters can be safely migrated to Luminous. On the long run, however, users who have previously deployed FileStore are likely to want to transition to BlueStore in order to take advantage of the improved performance and robustness. However, an individual OSD cannot be converted in place. The “conversion” is, in reality, the destruction of a Filestore and the creation of a Bluestore OSD, while the cluster takes care every time of evacuating the old OSD, replicate its content into other OSDs, and then rebalance the content once the new Bluestore is added to the cluster.