Hi, this solved my problem! I forgot the permissions on the cache pool Best Robert -----Ursprüngliche Nachricht----- Von: Kees Meijs <kees@nefos.nl> Gesendet: Montag, 16. September 2019 13:21 An: Eikermann, Robert <eikermann@se-rwth.de>; Fyodor Ustinov <ufm@ufm.su>; Wido den Hollander <wido@42on.com> Cc: ceph-users@ceph.io Betreff: Re: [ceph-users] Re: Activate Cache Tier on Running Pools Hi Robert, As long as you triple-check permissions on the cache tier (should be the same as your actual storage pool) you should be fine. In our setup I applied this a few times. The first time I made the assumption permissions would be inherited or not applicable but IOPs get redirected towards the tier and therefore permissions should be sane. It stopped all IOPs until I removed the overlay again. But alas; some VMs died already. Later on I extra checked the permissions and all was well. K. On 16-09-2019 13:12, Eikermann, Robert wrote:
That would be the case for me. I think all data during one day would fit into the cache, and we could slowly flush back over night (or even over the weekend). But my impression is, I would have to test it. So my initial question: Do I have to stop all VMs before activating the cache? And restart one by one with the cache enabled?