During our regular maintenance the GlusterFS cluster started to misbehave. This lead to errors on the storage side and broken Gluster volumes and therefore inaccessible Persistent Volumes (PV) bound to Persistent Volume Claims (PVC). We're working on recovering each volume one-by-one and will bring back the cluster into a stable state.
Update 5.4.2017 14:00
As of now all Gluster volumes are healthy again and PVs can be used as usual. We apologize for this incident and be assured that we further invest in stability of our Gluster cluster. If you have any issue with your application regarding persistent storage, feel free to write us under firstname.lastname@example.org.