Comment 5 for bug 1083540

I was unclear in (1) - I meant that the user and key used by nova-compute can be configured by nova, and don't need to be passed from cinder to nova-compute. Cinder would need its own configuration for user and key to use, as well as pool and monitor addresses.

(2) allows you to use more than one ceph cluster from the same compute host, and lets configuration be simpler for compute hosts. It would still be possible to use ceph.conf (qemu is actually the one reading it via librados), but it would not be required. Monitor addresses and pool really should be passed from cinder, since they are part of identifying the volume uniquely (the namespaces being cluster (determined by monitor addresses), pool, and image).