Ivan, I don’t think that ceph in containers is ready yet. The biggest problem is that the mount namespace is private in docker 1.7. I can’t mount the rbd volumes in one container and link them in other containers. On ubuntu or redhat, I can mount them on the host, but in RancherOS, I can’t see how to do that, given the need for the ceph utilities.
There are a few issues and pull requests to get this fixed, but I don’t know whether they will make docker 1.8 or be added to rancher’s system-docker:
–Bill