[PVE-User] RBD Storage from 6.1 to 3.4 (or 4.4)

[Fabrizio Cuseo]

I have installed a new cluster with the last release, with a local ceph storage.
I also have 2 old and smaller clusters, and I need to migrate all the VMs to the new cluster.
The best method i have used in past is to add on the NEW cluster the RBD storage of the old cluster, so I can stop the VM, move the .cfg file, start the vm (all those operations are really quick), and move the disk (online) from the old storage to the new storage.

But now, if I add the RBD storage, copying the keyring file of the old cluster to the new cluster, naming as the storage ID, and using the old cluster monitors IP, i can see the storage summary (space total and used), but when I go to "content", i have this error: "rbd error: rbd: listing images failed: (95) Operation not supported (500)".

If, from the new cluster CLI, i use the command: 

rbd -k /etc/pve/priv/ceph/CephOLD.keyring -m 172.16.20.31 ls rbd2

I can see the list of disk images, but also the error: "librbd::api::Trash: list: error listing rbd trash entries: (95) Operation not supported"


The new cluster ceph release is Nautilus, and the old one is firefly.

Some idea ? 

Thanks in advance, Fabrizio