Comment 3 for bug 1323707

Another problem that we can have old "xfs" (or other fs) after some previous installations right after we create new partition during provisioning. And it may fail "ceph-deploy osd prepare node-4:/dev/sdb2" command too. So we need to make sure we clear old filesystems from the newly created partition (/dev/sdb2) not the entire disk (/dev/sdb). I've updated https://review.openstack.org/95795 to address this.