Afaik you can configure the use of an rbd device like below. - Am I correct in assuming that the first one is not recommended because it can use some caching? (I thought I noticed a speed difference between these 2, and assumed it was related to caching). - I guess in both cases the kernel module is used and same libraries are used? - Are there any other (dis)advantages? 1. via mapped rbd device <disk type='block' device='disk'> <driver name='qemu' type='raw' cache='writeback'/> <source dev='/dev/rbd/rbd/vps-test2'/> <target dev='vda' bus='virtio'/> <boot order='2'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x0c' function='0x0'/> </disk> 2. direct <disk type='network' device='disk'> <driver name='qemu' type='raw' cache='writeback'/> <auth username='rbd.vps'> <secret type='ceph' uuid='9b185c64-8ca2-4e5e-b566-fb8a56b87e2c'/> </auth> <source protocol='rbd' name='rbd/vps-test2'> <host name='192.168.10.111' port='6789'/> <host name='192.168.10.112' port='6789'/> <host name='192.168.10.113' port='6789'/> </source> <target dev='sda' bus='scsi'/> <boot order='1'/> <address type='drive' controller='0' bus='0' target='0' unit='0'/> </disk> _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com