Hello guys, We have been reading the docs, and trying to reproduce that process in our Ceph cluster. However, we always receive the following message: ``` librbd::Migration: prepare: image has watchers - not migrating rbd: preparing migration failed: (16) Device or resource busy ``` We tested with both RDB blocks mounted with kRBD, and with librbd via KVM/qEMU system. Both cases result in the same result. For KRBD, we understood that it is not supported right now, but for librbd it seems that it should be supported somehow. How do you guys handle those situations? We have the following use cases that might need an image to migrate between pools while the client is still consuming it. - RBD images that are consumed via the iSCSI gateways - RBD images mounted (rbd map) in hosts - RBD images used by KVM/Libvirt Does Ceph support a live migration of images between pools while the clients/consumers are still using those volumes? [1] https://docs.ceph.com/en/quincy/rbd/rbd-live-migration/