Hello ! We're planning a new cluster without Ceph storage. We will use an iSCSI pureStorage array for all storage except object storage. PureStorage provide only a cinder driver. So we will need to user boot on volume nova instances. My question is about glance. PureStorage speak about Image Cache since Liberty: https://support.purestorage.com/Solutions/OpenStack/z_Legacy_OpenStack_Reference/OpenStack%C2%AE_Liberty%3A_A_Look_at_the_Glance_Image-Cache_for_Cinder But I wonder if using the cinder backend of glance is a better, simpler, transparent option ?