Get crush location
Generate a CRUSH location for the given entity
The CRUSH location consists of a list of key=value pairs, separated by spaces, all on a single line. This describes where in CRUSH hierarhcy this entity should be placed.
--cluster <clustername>
name of the cluster (see /etc/ceph/$cluster.conf)
--type <osd|mds|client>
daemon/entity type
--id <id>
id (osd number, mds name, client name)